Android 6 Essentials

Android6Essentials

TableofContents

Android6Essentials

Credits

AbouttheAuthor

Acknowledgments

AbouttheReviewer

www.PacktPub.com

Supportfiles,eBooks,discountoffers,andmore

Whysubscribe?

FreeaccessforPacktaccountholders

Preface

Whatthisbookcovers

Whatyouneedforthisbook

Whothisbookisfor

Conventions

Readerfeedback

Customersupport

Downloadingtheexamplecode

Downloadingthecolorimagesofthisbook

Errata

Piracy

Questions

1.AndroidMarshmallowPermissions

AnoverviewofAndroidpermissions

Permissions

Permissiongroupdefinitions

Permissionsthatimplyfeaturerequirements

Viewingthepermissionsforeachapp

UnderstandingAndroidMarshmallowpermissions

Anoverview

Permissiongroups

Runtimepermissions

Takingcodingpermissionsintoaccount

Testingpermissions

Codingforruntimepermissions

Bestpracticesandusagenotes

Minimalismisagreatoption

Askingfortoomanypermissionsatonce

Honestycanbeagreatpolicy

Needsupporthandlingruntimepermissions?

Somepermissionsarenormalandsafertouse

Summary

2.AppLinks

TheAndroidIntentsystem

Creatingawebsiteassociation

Whythisfile?

Triggeringapplinkverification

Applinksettingsandmanagement

Testingapplinks

Checkingmanifestandlistingdomains

TheDigitalAssetLinksAPI

Testingourintent

Checkingpoliciesusingadb

Summary

3.Apps’AutoBackup

Anoverview

Databackupconfiguration

Includingorexcludingdata

Thebackupconfigurationsyntax

Optingoutfromappdatabackup

Backupconfigurationtesting

Settingbackuplogs

Testingthebackupphase

Testingtherestorephase

Troubleshooting

Importantbytes

Whattoexcludefromthebackup

BackupAgentandbackupevents

Summary

4.ChangesUnfold

Power-savingmodes

TheDozemode

Whathappenstoappswhenadeviceisdozing?

TestingappswithDozemode

TheAppStandbymode

WhathappenstoappswhenintheAppStandbymode?

TestingappswiththeAppStandbymode

Excludedappsandsettings

Tips

Removablestorageadoption

ApacheHTTPclientremoval

Notifications

Textselection

Supportlibrarynotice

AndroidKeystorechanges

Wi-Fiandnetworkingchanges

Runtime

Hardwareidentifier

APKvalidation

USBconnection

DirectShare

Whatifwehavenothingtoshare?

DirectSharebestpractices

Voiceinteractions

TheAssistAPI

BluetoothAPIChanges

Bluetoothstylussupport

ImprovedBluetoothlowenergyscanning

Summary

5.Audio,Video,andCameraFeatures

Audiofeatures

SupportfortheMIDIprotocol

MidiManager

Digitalaudiocaptureandplayback

Audioandinputdevices

Informationonaudiodevices

ChangesinAudioManager

Videofeatures

android.media.MediaSync

MediaCodecInfo.CodecCapabilities.getMaxSupportedInstances

Whydoweneedtoknowthis?

MediaPlayer.setPlaybackParams

Camerafeatures

TheflashlightAPI

ThereprocessingAPI

android.media.ImageWriter

android.media.ImageReader

Changesinthecameraservice

Summary

6.AndroidforWork

Behavioralchanges

Theworkprofilecontactsdisplayoption

Wi-Ficonfigurationoptions

TheWi-Ficonfigurationlock

WorkPolicyControlleraddition

DevicePolicyManagerchanges

Single-usedeviceimprovements

Silentlyinstalling/uninstallingapps

Improvedcertificateaccess

Automaticsystemupdates

Third-partycertificateinstallation

Datausagestatistics

Managingruntimepermissions

VPNaccessanddisplay

Workprofilestatus

Summary

7.ChromeCustomTabs

WhatisaChromecustomtab?

WhatisWebView?

Customizationoptions

WhentouseChromecustomtabs

Theimplementationguide

CanweuseChromecustomtabs?

CustomUIandtabinteraction

Thecustomactionbutton

Configuringacustommenu

Configuringcustomenterandexitanimations

Chromewarm-up

ConnectingtotheChromeservice

Warmingupthebrowserprocess

Creatinganewtabsession

SettingtheprefetchingURL

Customtabsconnectioncallback

Summary

8.Authentication

TheFingerprintauthenticationAPI

Howdoweusefingerprintauthentication?

Settingupfortesting

Credentials’GracePeriod

Cleartextnetworktraffic

So,whatdowedowiththecleartextnetworktrafficflag?

Summary

Index

Android6Essentials

Android6EssentialsCopyright©2015PacktPublishing

Allrightsreserved.Nopartofthisbookmaybereproduced,storedinaretrievalsystem,ortransmittedinanyformorbyanymeans,withoutthepriorwrittenpermissionofthepublisher,exceptinthecaseofbriefquotationsembeddedincriticalarticlesorreviews.

Everyefforthasbeenmadeinthepreparationofthisbooktoensuretheaccuracyoftheinformationpresented.However,theinformationcontainedinthisbookissoldwithoutwarranty,eitherexpressorimplied.Neithertheauthor,norPacktPublishing,anditsdealersanddistributorswillbeheldliableforanydamagescausedorallegedtobecauseddirectlyorindirectlybythisbook.

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Firstpublished:November2015

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CreditsAuthor

YossiElkrief

Reviewer

PavelPavlasek

CommissioningEditor

EdwardGordon

AcquisitionEditor

ReshmaRaman

ContentDevelopmentEditor

RiddhiTuljapurkar

TechnicalEditor

GauravSuri

CopyEditor

StutiSrivastava

ProjectCoordinator

SanchitaMandal

Proofreader

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Indexer

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ProductionCoordinator

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CoverWork

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AbouttheAuthorYossiElkriefisanAndroidenthusiastwithover7yearsofexperienceintheAndroidplatformandiscurrentlyworkingasanAndroidarchitectandgroupleaderatTikalKnowledge.

Amonghispreviousexperiences,thenoteworthyonesincludeooVoo,Fiverr,Mobli,andGlide,reachingouttoover135millionusersworldwide.

YossiisamentoratGoogleLaunchpad,alectureronIoTandmobiledevelopment,andco-techleadontheMadgeraaccelerator.HecofoundedtheGDGBe’erShevagroupandco-leadsthegrouptoday,holdingtechnologyeventsforthetechnologycommunityinIsrael.Hehasaspouseandadaughter,andhelivesinBe’erSheva,Israel.

HismaininterestsareLiverpoolFootballClubandhisAndroidminicollectiblescollection,withover120differentpieces.YoucanfindhimonLinkedInathttps://il.linkedin.com/in/yossielkrief,onGitHubatMaTriXy,andonGoogle+atYossi.Elkrief.

https://il.linkedin.com/in/yossielkrief

AcknowledgmentsFirst,Iwanttothankmyfamilyfortheirpatience,love,andendurancewithmetakingyetanotherchallenge,reducingtheamountoftimeIcanspendwiththem.

ToIrit,mywife,fortheconstantloveandsupportandrememberingtofeedmewhenIcouldn’tremembertofeedmyself.

ToMia,mydaughterIloveyou.

Tomymotherandfather,whomIloveandcherish.

Tomyfriends,forbeingtherewiththeircodingarmoronandforgivingmethechancetoshine.

Tomymentor,friend,andfamily,IsraelMali;thankyouforguidingmefor15years,helpingmecarvemycareerpath.Mayyourestinpeace.

IwanttothankPacktPublishingforthisopportunityandforpublishingmyfirstbook.AspecialthankstoRiddhiTuljapurkarforallthehelpandguidance.

Lastbutnotleast,IchallengeyoutotryouttheChubbyBunnychallengeathttp://icebreakerideas.com/chubby-bunny-challenge/.

http://icebreakerideas.com/chubby-bunny-challenge/

AbouttheReviewerPavelPavlasekhasbeenanAndroiddeveloperforover5years,apartfrombeingalong-timeJavadeveloper.HedevelopswebinformationsystemsandAndroidapplications,andheispassionateaboutnewtechnologies.

Iwouldliketothanktomyfamilyfortheirsupportandinspiration—mywife,Daniela,andmychildren,Michaela,Jakub,andJuraj.IwouldalsoliketothankmycolleaguesandotherAndroiddevelopersI’vemet.

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PrefaceAndroid6willprimarilyfocusonimprovingtheoveralluserexperience,anditwillbringinafewfeatures,suchasaredesignedpermissionmodelinwhichapplicationsarenolongerautomaticallygrantedalloftheirspecifiedpermissionsatthetimeofinstallation,theDozepowerschemeforextendedbatterylifewhenadeviceisnotmanipulatedbytheuser,andnativesupportforfingerprintrecognition.

Ifyou’realreadyanAndroiddeveloper,you’reonlyafewstepsawayfrombeingabletouseyourexistingdevelopmentexperiencetoreachyouruserswhereverorwhenevertheywantorneedyourapp.

AsaprofessionalAndroiddeveloper,youhavetocreateproduction-readyappsforyourusers.Thisbookwillgiveyouwhatittakestoshippolishedappsaspartofadevelopmentteamatacompany,anindependentappdeveloper,orjustasaprogrammerusingAndroiddevelopmentbestpractices.

Bytheendofthebook,you’llbeabletoidentifycriticalareasforimprovementinanappandimplementthenecessarychangesandrefinementstoensureitmeetsAndroid’sCoreAppGuidelinespriortoshipping.

WhatthisbookcoversChapter1,AndroidMarshmallowPermissions,discusseshowtheAndroidpermissionsystemandmodelarevastandhavemadeafewchangesthatcanhelpappdevelopersandapplicationsgainmoretraction,installations,andgiveuserstheabilitytodecidewhenyourapplicationswillbeabletouseeachpermission-dependentfeature.Keepinmind,though,thatthisisjustastartingpointandAndroidMarshmallowstillneedstogainmarketshareandgetadoptedbyOEMs,enablinguserswiththefreedomofchoice.Youasanappdevelopermustprepareinadvanceandmakesureyourapplicationdevelopmentisforward-facing,allowingnewuserstoenjoythelatestupdatesassoonaspossiblewhilemaintainingahighlevelofperformanceforyourapplications.

Chapter2,AppLinks,talksabouthowapplinkinghasbecomepowerfulinAndroidMarshmallow.Thisallowsyou,theappdevelopers,helpthesystembetterdecidehowtoact.HandlingwebURLswillgiveyouwiderexposure,abiggerfunnelintoyourapps,andbetterexperience,whichyoucanprovidetoyourusers(sumsuptobetterratingsandmoredownloadsandviceversa).

Applinkingissimpletoimplement,easytounderstand,andisamust-havefeatureinthemobile/webworldtoday.Whileapplinkingenablesbetteractionhandlingforusersusingyourapplications,userscanhavemultipledevices,expectingthesamebehavioroneachdevice,andwouldbemoreengagediftheirdataandactionhandlingisallaround.

Chapter3,Apps’AutoBackup,informsyouthatAndroidMarshmallowbringswithitagreatbackupfeatureforapps,reducingfrictionforusersmigratingtonewdevices.

Inaworldfullofsuchdiverseapps,maximizingthebenefitsfromautomaticbackupsleadstoexcellentuserexperience.Thegoalofthisfeatureistounloadtheburdenandshortenthetimerequiredtosetupanewdevicewiththeuser’sfavoriteapps.Allowingtheuserstoenteryourappwithjustapasswordprompt,ifrequired,afteranewinstallationcanbeagreatexperience.Tryityourself!

Chapter4,ChangesUnfold,goesoverafewofthechangesinAndroidMarshmallow.Allofthesechangesareimportanttofollowandwillhelpyouinyourappdevelopmentcycles.Afewmorechangesarediscussedinfuturechapterswithamoredetailedapproach.

Chapter5,Audio,Video,andCameraFeatures,coversquiteafewchangesandadditionstoAndroidAPIs.AndroidMarshmallowismoreabouthelpingus,thedevelopers,achievebettermediasupportandshowcaseourideaswhenusingaudio,video,orcameraAPIs.

Chapter6,AndroidforWork,covershowAndroidMarshmallowhasbroughtinquiteafewchangestotheworldofAndroidforWork.Asdevelopers,weneedtoalwaysmaintainaviableconnectionwiththeneedsofanorganization.MakingsurethatwegooverandunderstandtheAndroidforWorkworldwiththechangesinMarshmallowhelpsusbuildandtargetenterpriseworkflowswiththeaddedbenefitofasimplerAPI.

Chapter7,ChromeCustomTabs,talksaboutthenewlyaddedfeature,Chromecustom

tabs,thatallowsusdeveloperstoembedwebcontentintoourapplication,modifytheUI,andadjustittoourapp’sthemeandcolorsandthelookandfeel.ThishelpsuskeeptheuserinourapplicationandstillprovideaniceUIandoverallfeel.

Chapter8,Authentication,discusshowAndroidMarshmallowgivesusanewAPItoauthenticateuserswiththefingerprintAPI.WecanusethesensorandauthenticatetheuserevenwithinourapplicationandsaveitforlaterusageifwewanttosavetheneedofuserloginusingtheCredentialsgraceperiodabilitiesAndroidMarshmallowhasintroduced.WealsocoveredawaytomakeourapplicationmoresecureusingHTTPSonly.TheStrictModepolicy,enforcedwiththehelpoftheusesCleartextTrafficflag,allowsustomakesurethatallthenodesweconnecttotheouterworldareexaminedtocheckifthere’saneedforasecureconnectionornot.

WhatyouneedforthisbookForthisbook,youwillrequirepreviousknowledgeoftheAndroidplatform,APIs,andtheapplicationdevelopmentprocess.Youwillalsoneedtosetupyourworkenvironmenttohaveatleastthefollowing:

AndroidStudio,whichcanbedownloadedfromhttps://developer.android.com/sdk/index.htmlThelatestAndroidSDKtoolsandplatforms.MakesurethatyouupgradetothelatestversionsandaddtheAndroid6.0(Marshmallow)platformifit’smissingAnAndroiddeviceishelpful,butyoumayuseanemulatorifyouprefer,oryoumayusethegreatsolutionofGenymotionasanemulator,athttps://www.genymotion.com/

https://developer.android.com/sdk/index.html

https://www.genymotion.com/

WhothisbookisforThisbookisforAndroiddeveloperswhoarelookingtomovetheirapplicationsintothenextAndroidversionwithease.Inthechaptersofthisbook,theauthorhasreferredtoAndroid6asAndroidMarshmallow.YoushouldhaveagoodunderstandingofJavaandpreviousAndroidAPIs,andyoushouldbeabletowriteapplicationswithAPIspriortoMarshmallow.

ConventionsInthisbook,youwillfindanumberoftextstylesthatdistinguishbetweendifferentkindsofinformation.Herearesomeexamplesofthesestylesandanexplanationoftheirmeaning.

Codewordsintext,databasetablenames,foldernames,filenames,fileextensions,pathnames,dummyURLs,userinput,andTwitterhandlesareshownasfollows:“ThesetTorchMode()methodhasbeenaddedtocontroltheflashtorchmode.”

Ablockofcodeissetasfollows:

<?xmlversion="1.0"encoding="utf-8"?>

<full-backup-content>

<excludedomain="database"path="sensitive_database_name.db"/>

<excludedomain="sharedpref"path="androidapp_shared_prefs_name"/>

<excludedomain="file"path="some_file.file_Extension"/>


</full-backup-content>

Anycommand-lineinputoroutputiswrittenasfollows:

$adbshellsmset-force-adoptabletrue

Newtermsandimportantwordsareshowninbold.Wordsthatyouseeonthescreen,forexample,inmenusordialogboxes,appearinthetextlikethis:“WhenheadingtoSettings|More|VPN,youcannowviewtheVPNapps.”

NoteWarningsorimportantnotesappearinaboxlikethis.

TipTipsandtricksappearlikethis.

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Chapter1.AndroidMarshmallowPermissionsAndroidpermissionshavebeenthereforaslongaswecanremember—sinceAndroid1.0,tobeexact.Throughtheyearsandwiththeevolvementofplatforms,theAndroidpermissionsmodelhasbeenmodifiedbyaddingnewpermissionsandtryingtoallowmoregranularcontroloverthepartofthedevicehardware/datatheapplicationhas.

Inthischapter,wewillreviewabitoftheAndroidpermissionsmodelthatwaspriortoAndroidMarshmallow,andwe’llfocusonthechangesitbringstothetable.WewillalsoexplainthechangesthatyouasadevelopermustdoinordertohandlealltheotherchangesandmakesureyourapplicationsworkasintendedonAndroidMarshmallow.

Inthischapter,wewillcoverthefollowing:

AnoverviewofAndroidpermissionsUnderstandingAndroidMarshmallowpermissionsHandlingcodepermissionswithbestpractices

AnoverviewofAndroidpermissionsInAndroid,eachapplicationrunswithdistinctsystemIDsknownasLinuxuserIDandGroupID.ThesystempartsarealsoseparatedintodistinctIDs,formingisolatedzonesforapplications—fromeachotherandfromthesystem.Aspartofthisisolatedlifecyclescheme,accessingservicesorotherapplications’datarequiresthatyoudeclarethisdesireinadvancebyrequestingapermission.

Thisisdonebyaddingtheuses-permissionelementtoyourAndroidManifest.xmlfile.Yourmanifestmayhavezeroormoreuses-permissionelements,andallofthemmustbethedirectchildrenoftheroot<manifest>element.

Tryingtoaccessdataorfeatureswithoutproperpermissionwouldgiveoutasecurityexception(usingaSecurityExceptionclass),informingusaboutthemissingpermissioninmostcases.

ThesendBroadcast(Intent)methodisexceptionalasitcheckspermissionsafterthemethodcallhasreturned,sowewillnotreceiveanexceptioniftherearepermissionfailures.Apermissionfailureshouldbeprintedtothesystemlog.NotethatinAndroidversionspriortoMarshmallow,missingpermissionswereduetomissingdeclarationsinthemanifest.Hence,itisimportantthatyoukeeppermissionsinmindwhenyoucomeupwiththefeaturelistforyourapp.

PermissionsWhenusingAndroidplatformasanapp,youhaverestrictionspreventingaccesstosomehardware,systemAPIs,privateuserdata,andapplicationdata.

PermissionisneededinordertoallowaccesstoaspecificAPI,data,orhardware;itwasaskedupontheinstallationofyourappupuntilAndroidMarshmallow.Mostpermissionsareusedtorestrictaccess.Whenapermissionisgranted,youthenhaveaccesstothatspecificrestrictedarea.Afeaturecanbeprotectedbyonepermissionatmost.

Theuses-permissionelementtakesanameattribute,android:name,whichisthenameofthepermissionyourapplicationrequires:

<uses-permissionandroid:name="string"android:maxSdkVersion="integer"/>

Didyouknowthattheandroid:maxSdkVersionattribute,addedinAPIlevel19,isusedtonotifytheversionoftheAPIfromwhichthispermissionshouldnotbegranted?ThisisusefulifapermissionisnolongerneededonhigherversionsoftheAPI.Forexample,takealookatthefollowing:

<uses-permission

android:name="android.permission.READ_EXTERNAL_STORAGE"

android:maxSdkVersion="18"/>

InAPI19,yourappdoesn’tneedtoaskforthispermission—it’sgrantedtoyou.

Yourapplicationcanalsoprotectitsowncomponents,suchasactivities,services,broadcastreceivers,andcontentproviderswithpermissions.

ItcanemployanyofthepermissionsdefinedbyAndroidanddeclaredbyotherapplications,oritcandefineitsown.

Formoreinformationonpermissions,youcanreadhttp://developer.android.com/reference/android/Manifest.permission.html.

http://developer.android.com/reference/android/Manifest.permission.html

PermissiongroupdefinitionsPermissionsaredividedintogroups.AccordingtoGoogle,wecansaythatapermissiongroupputstogetherrelatedpermissionsinasinglename/tag.YoucangrouppermissionstogetherusingthepermissionGroupattributeinsidethe<permission>element.

Permissionsgroupedinthesamepermissiongroupareshownasonegroupwhenapprovingpermissionsorwhencheckinganappforitspermissions.

ThepermissiongroupiswhatyouseewheninstallinganapplicationfromthePlayStore;forexample,takealookatthefollowingscreenshot:

Let’stakealookatthestructureofthepermission-grouptag:

<permission-groupandroid:description="stringresource"

android:icon="drawableresource"

android:label="stringresource"

android:name="string"/>

Theelementsoftheprecedingstructurecanbeexplainedasfollows:

android:description:Thisreferstosimpletextusedtodescribethegroup.android:icon:Thisreferstoaniconfromadrawableresourcethatrepresentsthepermission.android:label:Thisreferstoasimpletextnameforthegroup.android:name:Thisisthenameofthegroup.Itisusedtoassignpermissionstoaspecificgroup.

Thefollowingtableshowsyouthevariouscategoriesofpermissionsthatarethereinapermissionsgroup:

Permissionsgroup

In-apppurchases Deviceandapphistory

Contacts Calendar

Phone Photos,media,andfiles

Wi-Ficonnectioninformation Bluetoothconnectioninformation

Identity Cellulardatasettings

SMS Location

Microphone Camera

DeviceIDandcallinformation Wearablesensors/activitydata

Other

NoteAnypermissionsthatarenotpartofapermissionsgroupwillbeshownasOther.Whenanappisupdated,theremaybechangestothepermissionsgroupforthatapp.

PermissionsthatimplyfeaturerequirementsSomepermissionsareimpliedbyfeaturerequirements;wewillcoverthisnext.

Whendeclaringafeatureinthemanifest,wemustalsorequestthepermissionsthatweneed.

Let’ssay,forexample,thatwewanttohaveafeaturethatsetspicturesforourcontacts.IfwewanttotakeapictureviatheCameraAPI,thenwemustrequestaCamerapermission.

The<users-feature>tagmakessurewedeclarethatweneeddevicesthatsupporttherequiredfeatureforourapplicationtoworkandusethatfeature.Ifthisfeatureisnotarequiredfeatureandourappcanworkwithoutitbutwithfewerfeatures,wecanuseandroid:required="false",keepingitinmindthatthisfeatureisoptional.

The<uses-feature>declarationsalwaystakeprecedenceoverfeaturesimpliedbypermissions.Thecompletelistofpermissioncategoriesthatimplyfeaturerequirementscanbefoundathttp://developer.android.com/guide/topics/manifest/uses-feature-element.html#permissions.

http://developer.android.com/guide/topics/manifest/uses-feature-element.html#permissions

ViewingthepermissionsforeachappYoucanlookatthepermissionsforeachappusingthesettingsapportheadbshellcommand.

Tousethesettingsapp,gotoSettings|Apps.PickanappandscrolldowntoseethepermissionsthattheappusesYoucanseetheLollipopversioninthefollowingscreenshot:

InAndroidMarshmallow,theUIisdifferent.

Thesecondoptionistousetheadbshellcommandswiththeaaptcommand:

1. Listalltheapplicationsalongwiththeirinstallationpaths.Asanexample,let’strytofindoutFacebookgroups’apppermissionsusingthefollowingcommand:

adbshellpmlistpackages–f

Wecanusethe-3flagtojustshowthethird-partyappsinsteadoftheentirelist.

2. Oncewegetthepackagelocation(apk),weneedtopullitfromthedeviceviatheadbpull:

adbpull/data/app/com.facebook.groups-1/base.apk

3. Ourfinalsteptoshowpermissionsistouseaaptfoundinthebuild-toolsfolderofyourspecificbuildtoolsversion:

aaptdpermissionsbase.apk

Thisgivesusthefollowingscreenshotasaresult:

Toviewthepermissionsfortheentiredevice,takealookatthefollowingscreenshot:

Usinganadbcommand,youcanprintallknownpermissionsonthedevice.Thepackagemanager(pm)commandinsidetheadbcommandlookssomethinglikethefollowing:

$adbshellpmlistpermissions[options]<GROUP>

Listpermissionsgetthe[options]and<GROUP>arguments(bothoptional).

Here,optionscanbeasfollows:

-g:Thisreferstoalistofpermissionsorganizedbyagroup-f:Thisprintsalltheinformation-s:Thisprintsashortsummary,andthisiswhattheuserseesonscreenwhencheckingpermissionsorapprovingthem-d:Thislooksupandprintsonlypermissionsthatareconsidereddangerous-u:Thislistspermissionsvisibletotheuseronly

UnderstandingAndroidMarshmallowpermissionsAndroidMarshmallowintroducesanewapplicationpermissionsmodel,allowingasimplerprocessforuserswheninstallingand/orupgradingapplications.ApplicationsrunningonMarshmallowshouldworkaccordingtoanewpermissionsmodel,wheretheusercangrantorrevokepermissionsaftertheinstallation—permissionsarenotgivenuntilthereisuseracceptance.

Supportingthenewpermissionsmodelisbackward-compatible,whichmeansyourappscanstillbeinstalledandrunondevicesrunningolderversionsofAndroidusingtheoldpermissionsmodelonthosedevices.

AnoverviewWiththeAndroidMarshmallowversion,anewapplicationpermissionsmodelhasbeenintroduced.

Let’sreviewitabitmorethoroughly:

Declaringpermissions:Allpermissionsanappneedsaredeclaredinthemanifest,whichisdonetopreservebackwardcompatibilityinamannersimilartoearlierAndroidplatformversions.Permissiongroups:Asdiscussedpreviously,permissionsaredividedintopermissiongroupsbasedontheirfunctionalities:

PROTECTION_NORMALpermissions:Someofthepermissionsaregrantedwhenusersinstalltheapp.Uponinstallation,thesystemchecksyourapp’smanifestandautomaticallygrantspermissionsthatmatchthePROTECTION_NORMALgroup.INTERNETpermission:OneimportantpermissionistheINTERNETpermission,whichwillbegranteduponinstallation,andtheusercan’trevokeit.

Appsignaturepermissionsgranted:Theuserisnotpromptedtograntanypermissionsatthetimeofinstallation.Permissionsgrantedbyusersatruntime:Youasanappdeveloperneedtorequestapermissioninyourapp;asystemdialogisshowntotheuser,andtheuserresponseispassedbacktoyourapp,notifyingwhetherthepermissionisgranted.Permissionscanberevoked:Userscanrevokepermissionsthatweregrantedpreviously.Wemustlearnhowtohandlethesecases,aswe’lllearnlateron.

NoteIfanapptargetsanAndroidMarshmallowversion,itmustusethenewpermissionsmodel.

PermissiongroupsWhenworkingwithpermissions,wedividethemintogroups.Thisdivisionisdoneforfastuserinteractionwhenreviewingandapprovingpermissions.Grantingisdoneonlyonceperpermissiongroup.Ifyouaddanewpermissionorrequestanewpermissionfromthesamepermissiongroupandtheuserhasalreadyapprovedthatgroup,thesystemwillgrantyoutheaddedpermissionwithoutbotheringtheuserabouttheapproval.

Formoreinformationonthis,visithttps://developer.android.com/reference/android/content/pm/PermissionInfo.html#constants

Whentheuserinstallsanapp,theappisgrantedonlythosepermissionsthatarelistedinthemanifestthatbelongstothePROTECTION_NORMALgroup.

RequestingpermissionsfromthePROTECTION_SIGNATUREgroupwillbegrantedonlyiftheapplicationissignedwiththesamecertificateastheappwiththedeclaredpermission.

NoteAppscannotrequestsignaturepermissionsatruntime.

Systemcomponentsautomaticallyreceiveallthepermissionslistedintheirmanifests.

https://developer.android.com/reference/android/content/pm/PermissionInfo.html#constants

RuntimepermissionsAndroidMarshmallowshowcasedanewpermissionsmodelwhereuserswereabletodirectlymanageapppermissionsatapplicationruntime.Googlehasalteredtheoldpermissionsmodel,mostlytoenableeasierandfrictionlessinstallationsandauto-updatesforusersaswellasforappdevelopers.Thisallowsuserstoinstalltheappwithouttheneedtopreapproveeachpermissiontheapplicationneeds.Theusercaninstalltheappwithoutgoingthroughthephaseofcheckingeachpermissionanddecliningtheinstallationduetoasinglepermission.

Userscangrantorrevokepermissionsforinstalledapps,leavingthetweakingandthefreedomofchoiceintheusers’hands.

MostoftheapplicationswillneedtoaddresstheseissueswhenupdatingthetargetAPIto23.

TakingcodingpermissionsintoaccountWell,afteralltheexplanations,we’vereachedthecodingpart,andthisiswherewewillgetourcodinghandsdirty.Thefollowingarekeymethodsusedforhandlingpermissions:

Context.checkSelfPermission():ThischeckswhetheryourapphasbeengrantedapermissionActivity.requestPermission():Thisrequestsapermissionatruntime

EvenifyourappisnotyettargetingAndroidMarshmallow,youshouldtestyourappandpreparetosupportit.

TestingpermissionsIntheAndroidMarshmallowpermissionsmodel,yourappmustasktheuserforindividualpermissionsatruntime.Thereislimitedcompatibilitysupportforlegacyapps,andyoushouldtestyourappandalsotestaversiontomakesureit’ssupported.

Youcanusethefollowingtestguideandconductapptestingwiththenewbehavior:

Mapyourapp’spermissionsTestflowswithpermissionsgrantedandrevoked

Theadbcommandshellcanbequitehelpfultocheckforpermissions:

Listingapplicationpermissionsandstatusbygroupcanbedoneusingthefollowingadbcommand:

adbshellpmlistpermissions-g

Youcangrantorrevokepermissionsusingthefollowingadbsyntax:

adbshellpm[grant|revoke]<permission.name>

Youcangrantpermissionsandinstallapkusingthefollowingadbcommand:

adbinstall-g<path_to_apk>

CodingforruntimepermissionsWhenwewanttoadjustourapplicationtothenewmodel,weneedtomakesurethatweorganizeourstepsandleavenopermissionstranded:

Checkwhatplatformtheappisrunningon:WhenrunningapieceofcodethatissensitiveattheAPIlevel,westartbycheckingtheversion/APIlevelthatwearerunningon.

Bynow,youshouldbefamiliarwithBuild.VERSION.SDK_INT.

Checkwhethertheapphastherequiredpermission:Here,wegetourselvesabrandnewAPIcall:

Context.checkSelfPermission(Stringpermission_name).

Withthis,wesilentlycheckwhetherpermissionsaregrantedornot.

Thismethodreturnsimmediately,soanypermission-relatedcontrols/flowsshouldbedealtwithbycheckingthisfirst.

Promptingforpermissions:WehaveanewAPIcall,Activity.requestPermissions(String[]permissions,intrequestCode).Thiscalltriggersthesystemtoshowthedialogrequestingapermission.Thismethodfunctionsasynchronously.

Youcanrequestmorethanonepermissionatonce.Thesecondargumentisasimplerequestcodereturnedinthecallbacksothatyoucanrecognizethecalls.Thisisjustlikehowwe’vebeendealingwithstartActivityForResult()andonActivityResult()foryears.

AnothernewAPIisActivity.shouldShowRequestPermissionRationale(Stringpermission).

Thismethodreturnstruewhenyouhaverequestedapermissionandtheuserdeniedtherequest.It’sconsideredagoodpracticeafterverifyingthatyouexplaintotheuserwhyyouneedthatexactpermission.TheusercandecidetoturndownthepermissionrequestandselecttheDon’taskagainoption;then,thismethodwillreturnfalse.

Thefollowingsamplecodecheckswhethertheapphaspermissiontoreadtheuser’scontacts.Itrequeststhepermissionifrequired,andtheresultcallbackreturnstoonRequestPermissionsResult:

if(checkSelfPermission(Manifest.permission.READ_CONTACTS)!=

PackageManager.PERMISSION_GRANTED){

requestPermissions(newString[]{Manifest.permission.READ_CONTACTS},

SAMPLE_MATRIXY_READ_CONTACTS);

}

//Nowthisisourcallback

@Override

publicvoidonRequestPermissionsResult(intrequestCode,String

permissions[],int[]grantResults){

switch(requestCode){

caseSAMPLE_MATRIXY_READ_CONTACTS:

if(grantResults[0]==PackageManager.PERMISSION_GRANTED){

//permissiongranted-wecancontinuethefeatureflow.

}else{

//permissiondenied!-weshoulddisablethefunctionalitythat

dependsonthispermission.

}

}

}

Justtomakesureweallknowtheconstantsused,here’stheexplanation:

publicstaticfinalintPERMISSION_DENIED=-1:

Sinceit’sAPIlevel1,permissionhasnotbeengrantedtothegivenpackage

publicstaticfinalintPERMISSION_GRANTED=0:

Sinceit’sAPIlevel1,permissionhasbeengrantedtothegivenpackage.

Iftheuserdeniesyourpermissionrequest,yourappshouldtaketheappropriateaction,suchasnotifyingtheuserwhythispermissionisrequiredorexplainingthatthefeaturecan’tworkwithoutit.

NoteYourappcannotassumeuserinteractionhastakenplacebecausetheusercanchoosetorejectgrantingapermissionalongwiththedonotshowagainoption;yourpermissionrequestisautomaticallyrejectedandonRequestPermissionsResultgetstheresultback.

BestpracticesandusagenotesThenewpermissionsmodelhasbroughttolifeasmootherexperienceforusersandabitmorecode-handlingfordevelopers.Itmakesiteasiertoinstallandupdateappsandfeelcomfortablewithwhattheappsaredoing.

MinimalismisagreatoptionDon’tbeapermissionhog!Inourapplicationlifecycle,weshouldtrytominimizeourpermissionrequests.Askingforalotofpermissionsandmaintainingthemcanseemhazardousforsome,andweshouldtryandmakethefeaturesmoothandaskforthesmallestnumberofpermissionsasfaraspossibleinordertoallowrelaxed,undisturbedusage.Considerusingintentswheneverpossible—relyonotherapplicationsdoingsomeoftheworkforus(fewerpermissionsmeanslessfriction,turningagoodappintoagreatone).

AskingfortoomanypermissionsatonceUserscangetdistractedbytoomanydialogspoppingup,askingthemformoreandmorepermissions.Instead,youshouldaskforpermissionsasandwhenyouneedthem.

However,wehavesomeexceptionstoeveryrule.Yourappmayrequireafewpermissionstobeginwith,suchasacameraapplicationshowingthecamerapermissionsrightatthebeginning.However,settingthephototoyourcontactcanbedoneandrequestedonlywhentheusertriggersthatspecificaction.Trytomapyourflowandmakeiteasierforuserstounderstandwhatisgoingon.Userswillunderstandthatyou’verequestedpermissionsforcontactsiftheyhaveaskedtosetinformationtoacontactviayourapp.

Onemoresuggestion:appswithatutorialcanintegratetheessentialpermissions’requestinthetutorial,allowingtheuserstobetterunderstandtheflowandwhyeachpermissionisused.

HonestycanbeagreatpolicyWhenaskingforapermission,thesystemshowsadialogstatingwhichpermissionyourappwants,butitdoesn’tsaywhy.Consideruserswhohatebeingleftinthedarkthinkingwhythispermissionisneedednoworuserswhodenythepermissionsduetospeculation.Thingscanbeevenworse:sometimes,auser’scursormaybe2cmawayfromthe1-starratingortheuninstallbutton.

Thisiswhyit’sagoodideatoexplainwhyyourappwantsthepermissionsbeforecallingrequestPermissions().

Keepinmindthatmostdeveloperswillchooseatutorialbutalotofusersmaychoosetoskiptutorialswheneverpossible,soyoumustmakesurethatyoucanprovideinformationaboutpermissions,apartfromtheonesinthetutorial.

Needsupporthandlingruntimepermissions?Managingpermissionsiseasierwiththelatestrevisionofthev4orv13supportlibraries(23,whichisthesameastheAndroidMarshmallowAPIversion,soit’seasytoremember)

Thesupportlibrariesnowprovideseveralnewmethodstomanagepermissionsandworkproperlyonanydevicethatcanusetheselibraries.This,forinstance,savesyouthetimerequiredtocheckforasufficientAPIlevelregardlessofwhetherthedevicerunsAndroidMarshmallowornot.IfanappisinstalledonadevicerunningAndroidMarshmallow,properbehaviorisachieved—asifyou’rerunningthesameframeworkcalls.Evenwhenrunningonlowerversions,yougettheexpectedbehaviorfromthesupportlibrarymethods.

Thev4supportlibraryhasthefollowingmethods:

ActivityCompat.checkSelfPermission(Contextcontext,Stringpermission):

Thischeckswhetheryourapphasapermission.PERMISSION_GRANTEDisreturnediftheapphasthepermission;otherwise,PERMISSION_DENIEDisreturned.

ActivityCompat.requestPermissions(Activityactivity,String[]

permissions,intrequestCode:

Thisrequestspermissions,ifrequired.IfthedeviceisnotrunningAndroid6.0,youwillgetacallback.

ActivityCompat.OnRequestPermissionsResultCallback(intrequestCode,

String[]permissions,int[]grantResults):

ThispassesPERMISSION_GRANTEDiftheappalreadyhasthespecifiedpermissionandPERMISSION_DENIEDifitdoesnot.

ActivityCompat.shouldShowRequestPermissionRationale(Activityactivity,

Stringpermission):

ThisreturnstrueiftheuserhasdeniedapermissionrequestatleastonceandhasnotyetselectedtheDon’taskagainoption.

Accordingtothedesignpatterns,weshouldnowgiveourusersmoreinformationaboutthefeatureandwhythesepermissionsaresoimportanttotheapp.

NoteIfthedeviceisnotrunningAndroidMarshmallow,shouldShowRequestPermissionRationalewillalwaysreturnfalse.

ThePermissionCheckerclassisalsoincludedinv4.

ThisclassprovidesseveralmethodsforappsthatuseIPCtocheckwhetheraparticular

packagehasaspecifiedpermissionwhenIPCcallsaremade.

Androidhasacompatibilitymode,allowinguserstorevokeaccesstopermission-protectedmethodsforlegacyapps.Whenauserrevokesaccessinthecompatibilitymode,theapp’spermissionsremainthesamebutaccesstotheAPIsisrestricted.

ThePermissionCheckermethodverifiesapppermissionsinnormalaswellaslegacymodes.

NoteIfyourappactsasamiddlemanonbehalfofotherappsandneedstocallplatformmethodsthatrequireruntimepermissions,youshouldusetheappropriatePermissionCheckermethodinordertoensurethattheotherappisallowedtoperformtheoperation.

Thev13supportlibraryprovidesthefollowingpermissionmethods:

FragmentCompat.requestPermissions():

Thisrequestspermissions,ifrequired.IfthedeviceisnotrunningAndroid6.0,youwillgetacallback.

FragmentCompat.OnRequestPermissionsResultCallback:

ThispassesPERMISSION_GRANTEDiftheappalreadyhasthespecifiedpermissionandPERMISSION_DENIEDifitdoesnot.

FragmentCompat.shouldShowRequestPermissionRationale():

ThisreturnstrueiftheuserhasdeniedapermissionrequestatleastonceandhasnotyetselectedtheDon’taskagainoption.

Accordingtothedesignpatterns,weshouldnowgiveourusersmoreinformationaboutthefeatureandwhythispermissionissoimportanttotheapp.

NoteIfthedeviceisnotrunningAndroidMarshmallow,itwillalwaysreturnfalse.

Youcancheckoutthesampleprojectforthethreewaystohandlepermissions:

https://github.com/MaTriXy/PermissionMigrationGuide

Formoreinformationonpermissiondesignpatterns,readPatterns–PermissionsbyGoogleathttps://www.google.com/design/spec/patterns/permissions.html.

https://github.com/MaTriXy/PermissionMigrationGuide

https://www.google.com/design/spec/patterns/permissions.html

SomepermissionsarenormalandsafertouseTheAndroidsystemflagspermissionsaccordingtotheirprotectionlevels.Thelevelsaredescribesathttp://developer.android.com/reference/android/content/pm/PermissionInfo.html.

ThelevelthatisrelevanttoourdiscussionisPROTECTION_NORMAL,inwhichpermissionsareconsideredtohavelittleornoriskwhenapplicationshavethem.

Let’ssayyouwanttobuildaflashlightapp;allowingyourapptoturnontheflashisnotconsideredahugerisktoprivacyorsecurity,andthisiswhyflashlightpermissionisflaggedPROTECTION_NORMAL.

Whenyoudeclarenormalpermissionsinthemanifest,thesystemgrantsthesepermissionsautomaticallyatthetimeofinstallation.Thereisnoprompttograntpermissionsforanormalpermissionsgroup,andthesepermissionscan’tberevokedbyusers.

Thismeansthatyoucanbesurethatnormalpermissionsaregrantedatthetimeofinstallation.

Currently,thepermissionsclassifiedasPROTECTION_NORMALareasfollows:

android.permission.ACCESS_LOCATION_EXTRA_COMMANDS

android.permission.ACCESS_NETWORK_STATE

android.permission.ACCESS_WIFI_STATE

android.permission.ACCESS_WIMAX_STATE

android.permission.BLUETOOTH

android.permission.BLUETOOTH_ADMIN

android.permission.BROADCAST_STICKY

android.permission.CHANGE_NETWORK_STATE

android.permission.CHANGE_WIFI_MULTICAST_STATE

android.permission.CHANGE_WIFI_STATE

android.permission.DISABLE_KEYGUARD

android.permission.EXPAND_STATUS_BAR

android.permission.FLASHLIGHT

android.permission.GET_ACCOUNTS

android.permission.GET_PACKAGE_SIZE

android.permission.INTERNET

android.permission.KILL_BACKGROUND_PROCESSES

android.permission.MODIFY_AUDIO_SETTINGS

android.permission.NFC

android.permission.PERSISTENT_ACTIVITY

android.permission.READ_SYNC_SETTINGS

android.permission.READ_SYNC_STATS

android.permission.READ_USER_DICTIONARY

android.permission.RECEIVE_BOOT_COMPLETED

android.permission.REORDER_TASKS

android.permission.SET_TIME_ZONE

http://developer.android.com/reference/android/content/pm/PermissionInfo.html

android.permission.SET_WALLPAPER

android.permission.SET_WALLPAPER_HINTS

android.permission.SUBSCRIBED_FEEDS_READ

android.permission.TRANSMIT_IR

android.permission.VIBRATE

android.permission.WAKE_LOCK

android.permission.WRITE_SETTINGS

android.permission.WRITE_SYNC_SETTINGS

android.permission.WRITE_USER_DICTIONARY

com.android.alarm.permission.SET_ALARM

com.android.launcher.permission.INSTALL_SHORTCUT

SummaryAsyousaw,theAndroidpermissionsystemandmodelisvastandhasintroducedafewchangesthatcanhelpappdevelopersandapplicationsgainmoretractionandinstallationsandgivetheuserstheabilitytodecidewhenyourapplicationswillbeabletouseeachpermission-dependentfeature.Keepinmind,though,thatthisisjustastartingpointandAndroidMarshmallowstillneedstogainmarketshareandgetadoptedbyOEMs,enablinguserswithfreedomofchoice.Youasanappdevelopermustprepareinadvanceandmakesureyourapplicationdevelopmentisforward-facing,allowingnewuserstoenjoythelatestupdatesassoonaspossiblewhilemaintainingahighlevelofperformanceforyourapplications.

Inthenextchapter,wewillgooverasmallyetimportantfeatureintheAndroidMarshmallowversion:applinking.

Chapter2.AppLinksOneofthemajorimprovementstothenewAndroidMarshmallowversionispowerfulapplinking.Itallowstheassociationofyourappwithyourownedwebdomain.Withthisassociation,youasadeveloperallowthesystemtodeterminethedefaultappthatshouldhandleaparticularweblinkandskippromptinguserstoselectanapp.Savingclicksmeanslessfriction,whichmeansthatyoureachthecontentfaster;thisleadstousersanddevelopersbeinghappy.Inthischapter,wewillcoverthefollowingtopics:

TheAndroidIntentsystemCreatingawebsiteassociationTriggeringapplinkverificationApplinksettingsandmanagementTestingapplinks

TheAndroidIntentsystemAlmosteverydeveloperknowswhatanAndroidIntentsystemis,butwewillexplainitabitandlayoutthebasicprinciplesrequiredtounderstandtheapplinksfeature.TheAndroidIntentsystemcanbefoundintheAndroidplatform;thisallowsthepassingofdatainasmall,simplepackage.Intentmeansthatwewanttoperformanaction.Youmayalreadyknowaboutthebasicintents:

startActivity()

startActivityForResult()

startService()

sendBroadcast()

ThefollowingfigureshowsanAndroidIntentsystemforthestartActivity()andonCreate()intents:

Source:http://developer.android.com/guide/components/intents-filters.html

TheAndroidIntentsystemisaflexiblemechanismthatisusedtoenableappstohandlecontentandrequests.MultipleappsmaydeclarematchingURI(shortforUniformResourceIdentifier)patternsintheirintentfilters.Whenauserclicksonaweblinkthatdoesnothaveadefaultlaunchhandler,theplatformmaydisplayadialogfortheusertoselectfromalistofappsthathavedeclaredmatchingintentfilters.

Intentsarealsousedtotriggeractionsacrossthesystem,andsomeoftheseactionsaresystem-defined,suchasACTION_SEND(referredtoastheshareaction),whereyouasanappdevelopercanshare/sendspecificinformationtoanotherapplicationinordertocompleteanactionrequiredbyauser.

UntilAndroidMarshmallow,browsershandledeachlinkclickedontheWeb,andthesystemcheckedwhetheracustomURIschemewasavailable.YourapplicationcouldhandlespecificcustomactionsviathecustomURIscheme.Thiswastrickyattimesanddidn’tallowthehandlingoflinksunderanentirewebdomain.Now,it’spossible.AndroidMarshmallow’saddedsupportforapplinksallowsyou,asanappdeveloper,toassociateanappwithawebdomain.Automatically,thiswillallowyoutodeterminethedefaultapp

thatwillhandleaparticularweblinkinsteadofshowingtheselectedapplicationtohandlethedialog.

NoteIfyouwishtoreadmoreaboutintents,youcangotothefollowinglink:

http://developer.android.com/guide/components/intents-filters.html

http://developer.android.com/guide/components/intents-filters.html

CreatingawebsiteassociationYouasanappdeveloperaswellasawebsiteownerneedtodeclareawebsiteassociationwithanapp.ThedeclarationisdonebyhostingaJSONfile,whichisspecificallynamedassetlinks.json.Thefilemustresideinaspecificlocationonthedomaininquestion,suchas:https://<domain>:<optionalport>/.well-known/assetlinks.json

NoteThisfileisaccessedandverifiedovertheHTTPSprotocolandnotHTTP.

Whythisfile?TheJSONfileholdsinformationabouttheAndroidapplicationthatwillbethedefaulthandlerfortheURLsunderthisdomain.IntheJSONfile,youmusthavethefollowingstructure:

[{

"relation":["delegate_permission/common.handle_all_urls"],

"target":{

"namespace":"android_app",

"package_name":"com.yourapp.androidapp",

"sha256_cert_fingerprints":[""]

}

}]

Thefollowingaresomeelementsoftheprecedingstructure:

package_name:Thisisthepackagenamefromyourapp’smanifestsha256_cert_fingerprints:ThisistheSHA-256fingerprintofyourapp

Usethefollowingcommandifyoudon’thavethisSHA(shortforSecureHashAlgorithm):

keytool-list-v-keystoreapp_release_signing.keystore

TriggeringapplinkverificationYoucanrequestautomaticverificationforanyapplinksdeclaredintheassetlinks.jsonfile.Requestingaverificationisdonebyaddingtheandroid:autoVerifyattributetoeachintentfilterinthemanifestandsettingittotrue.

Let’ssayweownaWhatsAppapplicationanddomain.Wewanttoautoverifyanintentfilterthathastheandroid.intent.action.VIEWaction.

ThefollowingisasampleactivityfromWhatsAppthathandlesapplinksandtheautoverificationattribute:

<activityandroid:name="com.whatsapp.XXX"…>

<intent-filterandroid:autoVerify="true">

<actionandroid:name="android.intent.action.VIEW"/>

<categoryandroid:name="android.intent.category.DEFAULT"/>

<categoryandroid:name="android.intent.category.BROWSABLE"/>

<dataandroid:scheme="http"android:host="www.whatsapp.com"/>

<dataandroid:scheme="https"android:host="www.whatsapp.com"/>

</intent-filter>

</activity>

Theandroid:autoVerifyattributealertstheplatformtoverifyapplinkswhentheappisinstalled.Iftheapplink’sverificationfails,yourappwillnotbesetasthepreferredapptohandletheselinks.Ifthereisnopreferredapptohandletheselinkswheneverauseropensoneofthem,adialogtochooseanappisdisplayed.

Ifauserhasusedthesystemsettingsandsetanappasthepreferredapp,thenthelinkwillgodirectlytotheappbutnotbecausetheverificationwassuccessful.

ApplinksettingsandmanagementForeasymanagement,youcanenterthesystemsettingsandtweaktheURLhandlingbynavigatingtoSettings|Apps|Appinfo|Openbydefault.

TestingapplinksAswitheverynewfeatureweadd,wemusttesttheapplinksfeaturethatwewilladdtoourapplication.

CheckingmanifestandlistingdomainsOurfirststepistogooverthemanifestandmakesureallthedomainsareregisteredcorrectlyandallintentfiltersarewelldefined.Onlythelinks/domainsunderallthecriteriamentionedinthefollowingbulletsaretheonesweneedtotest:

Theandroid:schemeattributewithavalueofHTTPorHTTPSTheandroid:hostattributewithadomainURIpatternThecategoryelement,whichcanbeoneofthefollowing:

android.intent.action.VIEW

android.intent.category.BROWSABLE

TheDigitalAssetLinksAPIWecanusetheDigitalAssetLinksAPItoconfirmthatourlink’sJSONfileisproperlyhostedanddefinedusingthefollowingsyntax:

https://digitalassetlinks.googleapis.com/v1/statements:list?

source.web.site=https://<DOMAIN>:<port>&

relation=delegate_permission/common.handle_all_urls

TestingourintentNowthatwehaveconfirmedthatthehostedJSONfileisvalid,wewillinstalltheapponourdeviceandwaitforatleast20-30secondsfortheverificationprocesstocomplete.Afterthis,wecancheckwhetherthesystemhasverifiedourappandsetthecorrectlink-handlingpoliciesusingthefollowingsyntax:adbshellamstart-aandroid.intent.action.VIEW\-c

android.intent.category.BROWSABLE\-d"http://<DOMAIN>:<port>"

Forexample,ifwetakeYouTubevideos,wecantriggertheYouTubeapptoopenthevideodirectlyusingthefollowingcommand:

adbshellamstart-aandroid.intent.action.VIEW-c

android.intent.category.BROWSABLE-d"http://youtu.be/U9tw5ypqEN0"

CheckingpoliciesusingadbAndroidDebugBridge(adb)canhelpuscheckexistinglink-handlingpoliciesforallapplicationsinourdeviceusingthefollowingcommand:

adbshelldumpsyspackagedomain-preferred-apps

Thefollowingscreenshotistheresultoftheprecedingcommand:

Anotheroptionisasfollows:

adbshelldumpsyspackaged


NoteWemustwaitatleast20-30secondsaftertheinstallationforthesystemtocompletetheverificationprocess.

Thefollowinglistingindicatesapps’associationwithdomainsperuser:

Package:Thisreferstotheapp’spackagename,asdeclaredinitsmanifestDomains:Thisreferstothelistofhostswhoseweblinksarehandledbythisapp;blankspacesareusedasdelimitersStatus:Thisreferstothecurrentlink-handlingsettingforthisapp

Passingtheverificationandandroid:autoVerify="true"willshowastatusofalways.

Thehexadecimalnumberafterthestatus(asshownintheprecedingscreenshot)istheAndroidsystem’srecordoftheuser’sapplinkagepreferences.Itdoesnotindicatethattheverificationhassucceeded.

NoteTheusercanchangetheapplinksettingsbeforetheendoftheverificationprocess,whichmeansthatwemayseeafalsepositiveforasuccessfulverification.Userpreferencestakeprecedenceoverprogrammaticverification,sowewillseethatthelinkgoesdirectlytoourappwithoutdisplayingadialog,asifverificationhadsucceeded.

SummaryAswesaw,applinkinghasbecomepowerfulinAndroidMarshmallow.Thisallowsyou,theappdevelopers,helpthesystembetterdecidehowtoact.HandlingwebURLswillgiveyouwiderexposure,abiggerfunnelforyourapps,andbetterexperience,whichyoucanprovidetoyourusers(whichinturnleadstobetterratings,moredownloads,andviceversa).

Applinkingissimpletoimplement,easytounderstand,andisamust-havefeatureinthemobile/webworldtoday.Whileapplinkingenablesbetteractionhandlingforthoseusingyourapplications,userscanhavemultipledevices,expectingthesamebehavioroneachdevice,andwouldbemoreengagediftheirdataandactionhandlinghappenssmoothly.Thisbringsustoournextchapter,whichwillteachyouhowtobackupusersettingsandmore.

Chapter3.Apps’AutoBackupHaveyouevertakenthetimetosetupanapponyourphone,useitforawhile,pourinalotofcontent,andswitchphonesduetoamishapjusttodiscoverthatyourdataandsettingshavegonewiththewind?

OneofthekeyfeaturesofAndroidMarshmallowisthatitsupportsfullautomaticdatabackupandrestoreforuserapps.Thisimprovestheuserexperience,makestheoverallengagementmorefun,andshortenstheboardingtimeformultipledevices.Likewediscussedinthepreviouschapters,happyusersleadtohappydevelopers.

Youcanunloadtheburdenofsettingupanewdevice;itdoesn’tmatterwhetherit’sanaddeddeviceorareplacement.Theuserwillendupwiththesameappconfigurationanddata,allowingworktobemoredevice-agnostic.Forthisfeaturetobeenabledonyourapplications,youmusttargettheAndroidMarshmallowSDK’sversion23;noextracodeisneededbydefaulteventhoughyoucanconfigurethefeatureandallowspecificbehaviorwheneverrequired.Dataisautomaticallyrestoredwhenauserchangesorupgradesthedevice.

Inthischapter,wewilllearnhowthisfeatureworksandconfiguretheinformationthatwewanttobackup.We’llcoverthefollowingtopics:

AnoverviewDatabackupconfigurationBackupconfigurationtestingImportantbytes

AnoverviewTheautomaticbackupfeatureiscreatedbytakingthedatacreatedwithinyourappanduploadingittotheuser’sGoogleDriveaccount,keepingitencrypted.Thisdoesn’taffecttheuser’sdrivequotaoryourquota,forthatmatter.Eachappislimitedto25MBbackupperuser,andonceyoureachthatamount,yourappwillstopbackingup.Also,notethatit’scompletelyfree!

Backupisdoneincyclesof24hours,nightsonly,andit’sdoneautomatically,usuallywhenthedeviceisidle,charging,andconnectedtoaWi-Finetwork.Theseconditionsarethereforbatteryefficiency,datacharges,and,ofcourse,tokeeptheuserinterferencetoaminimum.AndroidsystemshaveaBackupManagerservice,whichuploadsalltheavailablebackupdatatothecloud.Switchingtoanewdeviceoruninstallingandreinstallingtheappwilltriggertherestoreoperation,whichinturncopiesthedataintotheapp’sdatadirectory.

NoteThisnewbehaviorallowsyoutokeepusingyourexistingbackupservicecallsaswell.

ToreadmoreabouttheAndroidBackupServicethatwasusedpriortoAndroidMarshmallow,headto:

https://developer.android.com/guide/topics/data/backup.html

https://developer.android.com/guide/topics/data/backup.html

DatabackupconfigurationWehavealotofdatathatwewanttobackupforourusers,butwealsodon’twanttobackupallthedata.Let’ssayweallagreenottobackupusers’passwordsorothersensitivedata,butwhatifyouhaveaspecificappconfigurationthatisgeneratedbasedonthedevicetheuserisusing?ThistooshouldbeexcludedinamannersimilartodevicetokenssuchasGoogleCloudMessaging(GCM)andothers.Iwouldrecommendthatyoufigureoutwhichdatayourappkeepspersistentlyandwhetherthisdatashouldandcanbedevice-agnostic.

Youcanconfigurewhatisbeingbackedupbesidestheautomaticallyexcludedfilesmentionedearlier.Thisconfigurationshouldbedeclaredinyourapp’smanifestviatheandroid:fullBackupContentattribute.YouwillneedtocreateanewXMLfilethatshouldresideinyourres/xmlfolder,andthiswillhavespecificrulesforthebackingupofyourapp’sdata.

IncludingorexcludingdataXMLfileconfigurationincludesasimplebatchofinclude/excludetags,whichindicatewhetherornotyouneedtobackupadirectoryoraspecificfile.Keepinmindthatbydefault,theXMLisreductive,whichmeansthatyoubackupeverythingpossibleunlessthereisaninstructiontoexcludeitinyourXML.

Anotherpossibleconfigurationistheconstructiveconfigurationinwhichyouspecifyonlythethingsyouwanttobackup,andtheywillbeaddedtothebackup.ThisconfigurationbehaviorisdonebyaddinganincludetagtoyourXML,andfromthenonward,itwillremainconstructive.

Aswecanseeinourexample,wespecifyabackupschemeconfigurationintheapp’smanifest:


<manifestxmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

package="com.yourapp.androidapp">

<uses-sdkandroid:minSdkVersion="16"/>

<uses-sdkandroid:targetSdkVersion="23"/>

<appandroid:fullBackupContent="@xml/androidapp_backup_config">

</app>

</manifest>

Afterdeclaringthefileinourmanifest,wealsoneedtoconstructitinourres/xmlfolder;forexample,takealookatthefollowing:



<excludedomain="database"path="sensitive_database_name.db"/>

<excludedomain="sharedpref"path="androidapp_shared_prefs_name"/>




Thisexamplebackupconfigurationexcludesonlyspecificdatafrombeingbackedup.Allotherfilesarebackedup.

ThebackupconfigurationsyntaxAlthoughyoushould’vesortedoutyourapp’sspecificpersistentdata,wecangoovertheconfigurationsyntaxthatshouldbeintheXML.ThesyntaxfortheconfigurationXMLfileisasfollows:


<includedomain=["root"|"sharedpref"|"database"|"file"|

"external"]path="string"/>

<excludedomain=["root"|"sharedpref"|"database"|"file"|

"external"]path="string"/>


Don’tforgettoreadtheexplanationforeachattributeandelementhere:

<include>:Youshouldusethistagwheneveryouwanttospecificallyaddaresourcefromanyoftheapprovedsortstothebackup.Rememberthatwheneveryouspecifyan<include>tag,thebackupbehaviorchangestoconstructive,andthesystemonlybacksupresourcesspecifiedwiththe<include>tags.<exclude>:Youshouldusethistagwheneveryouwanttoexcludeanyoftheapp’sresourcesfromthebackup.Asmentionedearlier,youshouldexcludesensitivedataandyourapp’sdevice-specificdata.Here,thebehaviorislikethis:thesystembacksupallofyourapp’sdataexcepttheresourcesspecifiedwiththe<exclude>tag.domain:Thisappearsonincludeaswellasexcludetags.Itallowsyoutodeclaretheresourcetypeyouwanttoincludeorexcludefromthebackup.Thedomainhasspecificvalidvaluesthatyoucanchoosefrom:

root:Thisimpliesthattheresourceshouldbeintheapp’srootdirectoryfile:ThisimpliesthattheresourceisafilelocatedintheFilesdirectoryandisaccessibleviathegetFilesDir()methoddatabase:ThisimpliesthatyourresourceisadatabasefilethatcanbelocatedviathegetDatabasePath()methodortheSQLiteOpenHelperclasssharedpref:ThisimpliesthatyourresourceisaSharedPreferencesobjectthatcanbeaccessedviathegetSharedPreferences()methodexternal:ThisimpliesthatyourresourceisafileinanexternalstoragelocatedinadirectoryaccessedbythegetExternalFilesDir()methodpath:ThisaStringpathtotheresourcethatyouwantincludedinorexcludedfrombackup

OptingoutfromappdatabackupOnsomeoccasions,youmightdecidethatyouwishnottousetheappdatabackupfeatureinyourapp.Insuchasituation,youwillbeabletonotifythesystemthatyourapphasoptedout.

Settingtheandroid:allowBackupattributetofalseinyourmanifestisdoneusingthefollowingcommand:

android:allowBackup="false"

BackupconfigurationtestingBynow,youhavecreatedabackupconfigurationandyoumight(should)testitandmakesurethatyourappsavesthedata,restoresit,andworkswithoutanyissues.

SettingbackuplogsBeforeyoutestyourapp’sconfiguration,youmightwanttoenablelogging;thisisdoneviaadb,whereyousettheparserlogpropertytoVERBOSE:

$adbshellsetproplog.tag.BackupXmlParserLoggingVERBOSE

Testingthebackupfeaturecanbesplitintotwoparts:

TestingthebackupphaseTestingtherestorephase

TestingthebackupphaseThebackupcanberunmanually,butfirst,youmustruntheBackupManagerviatheadbcommand:

$adbshellbmgrrun

AftertheBackupManagerisupandrunning,wecantriggerthebackupphaseviaadbandrunourapp’spackagenameasthe<PACKAGE.NAME>parameter:

$adbshellbmgrfullbackup<PACKAGE.NAME>

TestingtherestorephaseWeexecutedthebackupphaseandallwentwell.Now,wewanttotesttherestorephaseandverifythatallthebacked-updataisrestoredproperlyandwedidn’tmissoutonanyresource.Wemanuallyrunarestore(mustbedoneafteryourappdataisbackedup).Thisisdoneviatheadbshell,specifyingthepackagenameforyourappasthe<PACKAGE.NAME>parameter:

$adbshellbmgrrestore<PACKAGE.NAME>

NoteTherestoreactionstopsyourappandwipesitsdatabeforeactuallyperformingtherestoreoperation.

TroubleshootingIssuescanoccurinanyplace,includingourcase.Ifyourunintoissues,youshouldtryandclearthedatabyturningbackuponandoffbynavigatingtoSettings|Backup&reset,factoryresettingthedevice:

Youcanclearthedatausingthiscommand:

$adbshellbmgrwipe<TRANSPORT><PACKAGE.NAME>

The<TRANSPORT>tagisprefixedbycom.google.android.gms/.Toviewthelistoftransports,youcanrunfollowingadbcommand:

$adbshellbmgrlisttransports


ImportantbytesBeforewejumpintothenextchapter,let’sgothroughacoupleofimportantsubtopicswithintheAndroidapps’backupfeature.

Systembackupdoesnotincludethefollowing:

FileslocatedinCacheDirviathegetCacheDir()method(API1andabove)FileslocatedinCodeCacheDirviathegetCodeCacheDir()method(API21andabove)FileslocatedintheexternalstorageandnotinExternalFilesDirviathegetExternalFilesDir(Stringtype)method,wherethetypecanbeasfollows:

nullfortherootofthefiledirectoryAnyofthesetypesforaspecificsubfolder/directory:

android.os.Environment.DIRECTORY_MUSIC

android.os.Environment.DIRECTORY_PODCASTS

android.os.Environment.DIRECTORY_RINGTONES

android.os.Environment.DIRECTORY_ALARMS

android.os.Environment.DIRECTORY_NOTIFICATIONS

android.os.Environment.DIRECTORY_PICTURES

android.os.Environment.DIRECTORY_MOVIES

FileslocatedinNoBackupFilesDirviathegetNoBackupFilesDir()method(API21andabove)

WhattoexcludefromthebackupThoughwehavediscussedthisearlier,youmayneedtorevisewhichappdataiseligibleforbackup.

Amongtheexcludeddata,youmustexcludeanydevice-specificidentifiersthatareeitherissuedbyaserverorgeneratedonthedevice,includingtheGCMregistrationtoken.

Youmustalsoaddtheexcludinglogicforanyaccountcredentialsorothersensitiveinformation.

BackupAgentandbackupeventsYoucanimplementyourownBackupAgentattribute,whichallowsyoutolistentoevents.BackupAgenthasseveralcallbacksthatyoucanoverride,oneofwhichistheonRestoreFinished()method,whichiscalledafterasuccessfulrestoretakesplace.Youshouldaddtheandroid:fullBackupOnly="true"attributetoyourmanifestinadditiontoandroid:backupAgent;thiswillindicatethatwhileyourapplicationhasaBackupAgentattribute,AndroidMarshmallowandotherdeviceswillonlyperformfull-databackupoperations.

ThistechniquecancomeinhandywhenyouwanttoexcludeafewkeysfromyourSharedPreferencesbackup(device-specifictokens,GCMtokens,andsoon).InsteadofpartitioningSharedPreferencesintomultiplefiles,youcansimplyremovethekeysatrestoretimewhenonRestoreFinished()iscalled.

Keepinmindthatothersensitivedataisnotsupposedtobebackedupanyway.YoucanreadmoreaboutBackupAgentat:

http://developer.android.com/reference/android/app/backup/BackupAgent.html.

http://developer.android.com/reference/android/app/backup/BackupAgent.html

SummaryAndroidMarshmallowhasbroughtinagreatbackupfeatureforapps,reducingfrictionforusersmigratingtonewdevices.

Inaworldfullofdiverseapps,maximizingthebenefitsfromautomaticbackupsleadstobetteruserexperience.Thegoalofthisfeatureistounloadtheburdenandshortenthetimerequiredtosetupanewdevicewiththeuser’sfavoriteapps.

Allowingtheuserstoenteryourappwithmerelyapasswordpromptafterthenewinstallationcanbeagreatexperience;tryityourself!Youcancheckoutthesamplecodethat’sincludedorgototheGitHubrepositoryat:

https://github.com/MaTriXy/apps_autobackup_example

Inournextchapter,wewilldiveintomorechangesexecutedinAndroidMarshmallowasweunfolditsawesomeness.

https://github.com/MaTriXy/apps_autobackup_example

Chapter4.ChangesUnfoldAndroidMarshmallowholdssomechangesthatmightgetoverlooked.Alotofthesechangesareshortbutwillrequireyourfullattentiontofullyunderstandthemandmakesureyoudon’tmissoutwhentryingtousearemoved/deprecatedAPI,anewflow,oranewandimprovedAPI.

I’vebundledupagroupofchangesthatyoumightuseorneedtoknowandunderstandwhenbuildingyourapplicationsforAndroid6.0(Marshmallow):

Power-savingmodesRemovablestorageadoptionApacheHTTPclientremovalNotificationsTextselectionSupportlibrarynoticeAndroidKeystorechangesWi-FiandnetworkingchangesRuntimeHardwareidentifierAPKvalidationUSBconnectionDirectShareVoiceinteractionsTheAssistAPIBluetoothAPIchanges

Theprecedinggroupdoesn’tincludeaseparatechapterformajorchanges,forexample,thepermissionsmodelcoveredinChapter1,AndroidMarshmallowPermissions,oranimprovedAPI,suchasthevideo/audio/cameraAPIthatwewillcoverinthenextchapter.

Power-savingmodesAndroid6.0hasaddednewpower-savingmodes,DozeandAppStandby,prolongedbatterylifebyupto2timesaccordingtoGoogle’smeasurements.TheDozemodehasbeencreatedtoimprovethesleepefficiencyofidledevices,whiletheAppStandbymodehasbeendesignedtopreventappsfromeatinguppowerwhileintheidlestate.Onbothoccasions,plugginginthedevicetochargersallowsnormaloperationstoresume.

TheDozemodeDozingiswhenadeviceisunplugged,thescreenisoff,andit’sstationary(thiscanbedeterminedviasensors,suchastheaccelerometer)foradeterminedperiodoftime.Whatwegetisastatewherethesystemiskeptinthesleepstateaslongaspossible.WhenanAndroid6.0deviceisintheDozemode,notmuchwillhappeninthebackground,asshowninthefollowingfigure:

Inshort,everythingyouthinkwillhappeninthebackgroundwillnotactuallyhappen.

Whathappenstoappswhenadeviceisdozing?Whenadeviceentersthedozingstate,youwillencountersomebattery-efficientsystembehavior,whichwillincludethefollowing:

Networkaccessisrestrictedunlessyourappreceivesahigh-priorityGCMWakelocksareignoredbutaregrantedtoappsSyncsandjobsaredeferredusingthefollowing:

SyncadaptersJobScheduler(notallowedtorun;thisisenforcedbythesystem)

Alarmsaredeferred

NoteIfyouhaveimportantalarmsandneedtotriggertheUI:

UsethesetAndAllowWhileIdle()methodCan’tbeabused;thisisallowedonceevery15minutesWi-FiscansareoffGPSisoff

TheDozemodewillendshortlybeforeanysetAlarmClock()alarms;itcanalsoendwhenthestatesofbeingstationaryandunpluggedareexchanged.ExitingtheDozemode

willtriggerthedevicetoexecuteanyjobsandsyncsthatarepending.

TestingappswithDozemodeTestappsusingyourdevice(withAndroid6.0)andadbcommands:

1. Simulateanunpluggeddeviceusingthefollowingcommand:

$adbshelldumpsysbatteryunplug

Thiswillcauseyourbatteryicontoshowasifthedeviceisnotpluggedin.

2. Takethesteptothenextstateusingthefollowingcommand:

$adbshelldumpsysdeviceidlestep

Thiscanbeseeninthefollowingscreenshot:

3. Resetthebatterystatebacktoitsnormalconditionusingthefollowingcommand:

$adbshelldumpsysbatteryreset

Youcanalsolisttheavailablecommandsusingthefollowingcommand:

$adbshelldumpsysdeviceidle-h

Thisprintsmoreinformationaboutthedeviceidleusage,asshowninthefollowingscreenshot:

TheAppStandbymodeAppStandbyisaspecialmodethatappswillbeinwhenasystemdeterminesthatanappisidle.Anappisconsideredidleafteraperiodoftimeunlesstheappexhibitsthefollowingfeatures:

Ithasaforegroundprocessatthattime(anactivityorservice)ItdisplaysnotificationsonthelockscreenorinthenotificationtrayItwasexplicitlylaunchedbytheuserItwasmarkedasexcludedfromoptimizationsviathesettingsapp

WhathappenstoappswhenintheAppStandbymode?Ifthedeviceisunplugged,syncsandjobsaredeferredandnetworkaccessisrestricted.

Ifthedeviceispluggedin,thesystemreleasestheapplockinthestandbystate,allowingthedevicetoresumeaccesstothenetworkand/orexecuteanypendingjobsandsyncs.

NoteWhenintheidlestateforalongperiodoftime,thesystemallowsidleappstoaccessthenetworkjustonceaday.

TestingappswiththeAppStandbymodeTestappsusingyourdevice(withAndroid6.0)andadbcommands:

1. Simulatetheappthat’sgoingintothestandbymode:

$adbshellambroadcast-aandroid.os.action.DISCHARGING

$adbshellamset-inactive<AppPackageName>true

2. Simulatebywakingyourapp:

$adbshellamset-inactive<AppPackageName>false

3. Seewhathappenswhenyourappawakens.Testrecoveringgracefullyfromstandbymode.Checkwhetheryourapp’snotificationsandbackgroundjobsfunctionasyouwouldanticipate.

Youcansetyourappasinactiveviathefollowingcommand:

$adbshellamset-inactive<AppPackageName>true

Youcanalsocheckthestatusofyourappviathefollowingcommand:

$adbshellamget-inactive<AppPackageName>

NoteThesampletestwasdoneonGooglePhotosbehavior;allrightsarereserved.

Theconsoleoutput,forexample,isasfollows:

~adbshellamset-inactivecom.google.android.apps.photosfalse

~adbshellamget-inactivecom.google.android.apps.photos

Idle=false

~adbshellamset-inactivecom.google.android.apps.photostrue

~adbshellamget-inactivecom.google.android.apps.photos

Idle=true

ExcludedappsandsettingsYoucanexcludeappsfromtheAppStandbymodeviathesettingsapps,asmentionedearlier.Theproceduretodothisisasfollows:

1. GotoSettings|Apps.

2. Clickonthecog/gearicontoopentheConfigureappsscreen.

3. ChooseBatteryoptimization.

4. ThefollowingscreenshotshowsalistoftheappsexcludedfromtheAppStandbymode—thatis,theonesthatarenotoptimized.Youcanopentheselectionforallappsandchoosetheexactbehavioryourequireforeachapplication.

TipsHereareafewpointsandtipsforyoutonoteandremember:

UseisIgnoringBatteryOptimizations()withaPowerManagerinstanceandcheckwhetheryourappisonthewhitelistNavigatetheuserdirectlytotheconfigurationscreenusingthefollowing:

startActivity(new

Intent(Settings.ACTION_IGNORE_BATTERY_OPTIMIZATION_SETTINGS));

Performthefollowingstepstodisplayasystemdialogaskingaboutaddingaspecificapptothewhitelist:

1. AddtheREQUEST_IGNORE_BATTERY_OPTIMIZATIONSpermissiontotheapplication’smanifest.

2. CreateaURIpackagepointingtoyourapplication.3. WraptheURIinanintentandcallstartActivity()withitasshowninthe

followingcode:

Intentintent=new

Intent(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS,

Uri.parse("package:"+getPackageName()));

startActivity(intent);

Notethatifourappisalreadywhitelisted,thedialogwon’tbedisplayedagain

RemovablestorageadoptionAndroidMarshmallowallowsuserstoadoptexternalstoragedevices,suchasSDcards.Suchadoptionswillformatandencryptthestoragedeviceandmountitasinternalstorage.Oncedone,userscanmoveappsandapps’privatedatabetweenstoragedevices.Theandroid:installLocationpreferenceinthemanifestwillthenbeusedbythesystemtodeterminetheavailablelocationsforeachapp.WhatyouneedtokeepinmindisthatusingContextmethodsfordirectoriesorfilesandApplicationInfofieldswillreturnvaluesthatcanchangebetweenruns.YoushouldalwayscalltheseAPIsdynamically.Don’tusehardcodedfilepathsorpersistfullyqualifiedfilepaths.

TheContextmethodsareasfollows:

getFilesDir()

getCacheDir()

getCodeCacheDir()

getDatabasePath()

getDir()

getNoBackupFilesDir()

getFileStreamPath()

getPackageCodePath()

getPackageResourcePath()

TheApplicationInfofieldsareasfollows:

dataDir

sourceDir

nativeLibraryDir

publicSourceDir

splitSourceDirs

splitPublicSourceDirs

YoucandebugthisfeatureandenabletheadoptionofaUSBdriveconnectedviaanOTG(shortforOnTheGo)cableusingthefollowingcommand:

$adbshellsmset-force-adoptabletrue

FormoreonUSB,headtohttps://developer.android.com/guide/topics/connectivity/usb/index.html.

https://developer.android.com/guide/topics/connectivity/usb/index.html

ApacheHTTPclientremovalTheApacheHTTPclienthasbeendeprecatedforquitesometime—since2011orso.UsingthisclientonAndroid2.3andhigherwasnotrecommended;nowwithAndroid6.0Marshmallow,thisAPIhasbeenremoved.So,we’llusetheHttpURLConnectionclassinstead.

ThisAPIismoreefficient,reducesnetworkuse,andminimizespowerconsumption.

IfyouwishtocontinueusingtheApacheHTTPAPIs,youmustfirstdeclarethefollowingcompile-timedependenciesinyourbuild.gradlefile:

android{

useLibrary'org.apache.http.legacy'

}

NoteIfyouhavecompileerrorsintheAndroidstudio,youcanheadtothesequestionsandsolutionsonstackoverflow:

http://stackoverflow.com/q/30856785/529518http://stackoverflow.com/q/31653002/529518

http://stackoverflow.com/q/30856785/529518

http://stackoverflow.com/q/31653002/529518

NotificationsThereareafewchangestothenotificationsfeature,asfollows:

TheNotification.setLatestEventInfo()methodisnowremoved.Whenconstructingnotifications,wemustusetheNotification.Builderclass.UpdatinganotificationisalsodoneviatheNotification.Builderinstanceusingthesameinstanceofthebuilder,andcallingthebuild()methodwillgetusanupdatedNotificationinstance.Iflegacysupportisrequired,youcanuseNotificationCompat.Builderinstead,whichisavailableintheAndroidSupportLibrary.Theadbshelldumpsysnotificationcommandnolongerprintsoutnotificationtext.Theproperusagenowisadbshelldumpsysnotification--noredact.ThenewlyaddedINTERRUPTION_FILTER_ALARMSfilterlevelcorrespondstoanewmode:Alarmsonlydonotdisturb.ThenewlyaddedCATEGORY_REMINDERcategoryisusedforuser-scheduledreminders.ThenewlyaddedIconclassallowsiconstobeattachedtonotificationsviathesetSmallIcon()andsetLargeIcon()methods.TheupdatedaddAction()methodnowacceptsanIconobjectinsteadofadrawableresourceID.ThenewlyaddedgetActiveNotifications()methodallowsyoutofindoutwhichnotificationsarecurrentlyalive.Wecanobtainsomeknowledgeaboutwhattheuserisandisnotexpectingtoseeundernotificationswhenusingthefollowingmethods:

ThenewlyaddedgetCurrentInterruptionFilter()methodreturnsthecurrentnotificationinterruptionfilterinwhichnotificationsareallowedtointerrupttheuserThenewlyaddedgetNotificationPolicy()methodreturnsthecurrentnotificationpolicy

TextselectionPartofthematerialdesignguidespecificationsdiscusstextselectioninyourapplications.Usersselecttextwithinyourapp,andyounowhaveanAPItoincorporateafloatingtoolbardesignpatternthat’ssimilartoacontextualactionbar.Formoreinformationaboutthedesignspecifications,headtohttp://www.google.com/design/spec/patterns/selection.html#selection-item-selection.

Theimplementationstepsareasfollows:

1. ChangeyourActionModecallstostartActionMode(Callback,ActionMode.TYPE_FLOATING).

2. ExtendActionMode.Callback2.3. OverridetheonGetContentRect()methodandprovidecoordinatesforthecontent

Rectobjectintheview.4. CalltheinvalidateContentRect()methodwhenyouneedtoinvalidatetheRect

objectandit’spositionisnolongervalid.

http://www.google.com/design/spec/patterns/selection.html#selection-item-selection

SupportlibrarynoticeFloatingtoolbarsarenotbackward-compatible.AppcompattakescontroloverActionModeobjectsbydefault.Thiswillpreventfloatingtoolbarsfrombeingdisplayed.


1. CallgetDelegate()andsetHandleNativeActionModesEnabled()onthereturnedAppCompatDelegateobject.

2. Settheinputparametertofalse.

ThiscallwillreturncontrolofActionModeobjectstotheframework,allowing6.0devicestosupportActionBarorfloatingtoolbarmodesandallowingearlierversionstosupporttheActionBarmodes.

AndroidKeystorechangesFromAndroid6.0onward,theAndroidKeystoreprovidernolongersupportsDigitalSignatureAlgorithm(DSA).

Formoreinformationaboutkeystoreanditsusage,visithttps://developer.android.com/training/articles/keystore.html.

https://developer.android.com/training/articles/keystore.html

Wi-FiandnetworkingchangesAndroidMarshmallowhasintroducedafewchangestotheWi-FiandnetworkingAPIs.

ChangingthestateofWifiConfigurationobjectsisonlypossibleforself-createdobjects.YouarerestrictedfrommodifyingordeletingWifiConfigurationobjectscreatedbytheuserorotherapps.

Inearlierversions,forcingthedevicetoconnecttoaspecificWi-FinetworkusingenableNetwork()andsettingupdisableAllOthers=truecausedthedevicetodisconnectfromothernetworks.ThisdoesnothappeninAndroid6.0.WithtargetSdkVersion<=20,yourappispinnedtousetheselectedWi-Finetwork.WhentargetSdkVersion>=21,youneedtousetheMultiNetworkAPIsandensurethatnetworktrafficisassignedtothepropernetwork.FormoreinformationontheMultiNetworkAPI,refertohttps://developer.android.com/about/versions/android-5.0.html#Wireless.

https://developer.android.com/about/versions/android-5.0.html#Wireless

RuntimeTheAndroidART(shortforAndroidruntime)runtimewasalsoupdatedinAndroidMarshmallow,andthefollowingaretheupdates:

ThenewInstance()method:TheDalvik(anotherruntime)issueforthecheckingofaccessrulesincorrectlywasfixed.Ifyouwishtooverrideaccesschecks,callthesetAccessible()methodwiththeinputparametersettotrue.Usingthev7Appcompatlibraryorthev7Recyclerviewlibrary?Youmustupdatetothelatestversion.MakesurethatanycustomclassesreferencedfromXMLareupdatedsothattheirclassconstructorsareaccessible.Behaviorofthedynamiclinkerisupdated.TheARTruntimeunderstandsthedifferencebetweenalibrary’ssonameanditspath;searchbysonameisnowimplemented.Therewasanopenbugwiththisissuethatwasfixed;ifyouwishtoextendyourreading,visithere:

https://code.google.com/p/android/issues/detail?id=6670

https://code.google.com/p/android/issues/detail?id=6670

HardwareidentifierAndroid6.0hasintroducedamajorchangeforgreaterdataprotection;theWifiInfo.getMacAddress()andBluetoothAdapter.getAddress()methodsnowreturnaconstantvalueof02:00:00:00:00:00,whichmeansyoucan’trelyonthesemethodstogetinformation.

Now,whenyou’retryingtousesomeofthemethodsintheAPI,youneedtoaddpermissions:

WifiManager.getScanResults()andBluetoothLeScanner.startScan()needoneofthesetwopermissionsgranted:

TheACCESS_FINE_LOCATIONpermissionTheACCESS_COARSE_LOCATIONpermission

BluetoothDevice.ACTION_FOUND:ThismusthavetheACCESS_COARSE_LOCATIONpermission

NoteWhenadevicerunningAndroid6.0(Marshmallow)initiatesabackgroundWi-FiorBluetoothscan,externaldevicesseetheoriginasarandomizedMACaddress.

APKvalidationTheplatformnowperformsstrictvalidationofAndroidPackageKits(APKs).

IfafiledeclaredinthemanifestisnotpresentintheAPKitself,thentheAPKisconsideredcorrupted.RemovingcontentsfromtheAPKrequiresre-signingoftheAPK.

USBconnectionBydefault,theUSBconnectionischarge-only.UsersmustnowgrantpermissionstointeractviatheUSBport.Yourapplicationsshouldtakethisintoaccountandbeawarethatpermissionsmightnotbegranted.

DirectShareOneofthebestthingsabouttechnology,inmyhumbleopinion,isthatitgivesusersgreatoptionstointeractandbenefitfromthem.DirectSharecanbetreatedasagreatadditiontothelistofmerits,withgreat,fluiduserexperienceallaroundtheappworld.So,whatisDirectShare?Well,almosteveryapptodayusessomesortofinformation/dataexchangewithotherapplicationsontheuser’sdeviceorwiththeoutsideworldviathesharingmechanism.Thesharingmechanismexposesapieceofinformationfromoneapplicationtoanother.Usually,auserwillinteractwithafewclosecompanions(family,closefriends,orcolleagues),andthisiswhereDirectSharecomestoyouraid.

DirectShareisaboutasetofAPIsrequiredtomakesharingintuitiveandquickforusers.YoudefineDirectSharetargetsthatlaunchaspecificactivityinyourapp.ThesetargetsareshownintheSharemenu,allowingfastersharingandfluiddataflow.

WithDirectShare,userscansharecontenttotargets—say,contactsinotherapps.


1. DefineaclassthatextendstheChooserTargetServiceclass.2. Declareyourserviceinthemanifest.3. SpecifytheBIND_CHOOSER_TARGET_SERVICEpermissionandanintentfilter

SERVICE_INTERFACEaction.

Anexampleservicedeclarationisasfollows:

<serviceandroid:name=".MyChooserTargetService"

android:label="@string/McTs_name"android:permission=

"android.permission.BIND_CHOOSER_TARGET_SERVICE">

<intent-filter>

<actionandroid:name="android.service.chooser.ChooserTargetService"/>

</intent-filter>

</service>

Now,wehaveaservicedeclaredand,foreachtargetwewanttoexpose,weadda<meta-data>elementwiththeandroid.service.chooser.chooser_target_servicenameinyourappmanifest:

<activityandroid:name=".SampleDirectShareTarget"

android:label="@string/SampleDirectShareTarget_name">

<intent-filter>

<actionandroid:name="android.intent.action.SEND"/>

</intent-filter>

<meta-dataandroid:name="android.service.chooser.chooser_target_service"

android:value=".ChooserTargetService"/>

</activity>

Let’stakealookatthecodeinourservice:

publicclassMyChooserTargetServiceextendsChooserTargetService{

privateStringmDirectShareTargetName;

privatefinalintMAX_SHARE_TARGETS=5;

@Override

publicvoidonCreate(){

super.onCreate();

mDirectShareTargetName="SharingPersondemo#%d";

}

@Override

publicList<ChooserTarget>onGetChooserTargets(ComponentName

sendTarget,IntentFiltermatchedFilter){

ArrayList<ChooserTarget>result=new

ArrayList<ChooserTarget>();

for(inti=1;i<=MAX_SHARE_TARGETS;i++){

result.add(buildTarget(i));

}

return(result);

}

privateChooserTargetbuildTarget(inttargetId){

Stringtitle=String.format(mDirectShareTargetName,targetId);

Iconicon=Icon.createWithResource(this,

R.drawable.share_target_picture);

floattarget_value=((float)(25-targetId)/25);

ComponentNamecomponentName=new

ComponentName(MyChooserTargetService.this,TargetActivity.class);

Bundlebundle=newBundle();

bundle.putInt("simple_key",targetId);

return(newChooserTarget(title,icon,target_value,componentName,

bundle));

}

}

Youcanheadtothegistifyouwishtobetterviewthecode;youcanvisithttps://gist.github.com/MaTriXy/adeacdf5496bcdae5f42.

YouhavetoimplementtheonGetChooserTargets()methodasitwillbecalledwhendirect-shareistriggered.YoureturnalistofChooserTargetobjectsthatrepresentsharingentrypointstoyourapplication.TheonGetChooserTargets()resultsareincludedalongwiththeregularACTION_SENDactivityitself.So,weonlywantChooserTargetobjectsthatimprovetheflowandnotduplicates.

WhencreatingseveralChooserTargetobjects,eachofthemwillprobablypointtothesameactivity.Youmustensurethattheextrasbundlewillcontaindistinguishinginformationsothateachrequestwillbeunique.DonotputcustomParcelableobjectsinthisbundleasitwillcausecrashes.YoucanfindoutmoreaboutChooserTargetathttps://developer.android.com/reference/android/service/chooser/ChooserTarget.html#ChooserTarget

https://gist.github.com/MaTriXy/adeacdf5496bcdae5f42

https://developer.android.com/reference/android/service/chooser/ChooserTarget.html#ChooserTarget

Whatifwehavenothingtoshare?Sometimes,youwon’thaveanydirect-sharetargetsforaparticularrequest;then,returninganemptylistwouldbegreat.Youcanalsodisabletheserviceviaandroid:enabled="false"ifyouknowthatnoresultswillbeavailableuntilfutureusageoftheapp.AnotheroptionistoenabletheservicejustforAndroid6.0.ThiscaneasilybedoneusingBooleanresources:

Let’saddaBooleanresourcenamedis_share_targets_on:

Thedefaultvalueisres/values/bools.xml;setittofalseAndroid6.0isAPI23,soinres/values-v23/bools.xml,setittotrue

Addandroid:enabled="@bool/is_share_targets_on"toyourservicedeclaration

DirectSharebestpracticesThefollowingarefewofthebestpracticesfollowedinDirectShare:

Android6.0limitsthenumberofsharetargets,onlyshowingeightofthem.Providingmorethaneightsharetargetswillshowthebesteightaccordingtothescore.TheFAILEDBINDERTRANSACTIONexceptioncanpopinforavisitifyourlistoftargetsexceeds1MB.Trytolimit/caphowmanysharetargetsyoutrytoreturnfromyourChooserTargetServiceclass.Makesureyourapp’siconisshownproperlyasitwillbeappliedasabadgeovertheiconsthatyouuseforDirectSharetargets.

VoiceinteractionsVoiceinteractionsusuallyoriginatefromuservoiceaction.However,thevoiceinteractionactivitystartswithoutanyuserinput.AndroidMarshmallowhasanewvoiceinteractionAPIthat,togetherwithvoiceactions,allowsustobuildconversationalvoiceexperiencesintoourapps.UsetheisVoiceInteraction()methodtodeterminewhetheranactivityistriggeredbyavoiceaction.Then,youcanusetheVoiceInteractorclassandinteractwiththeuser.

Don’tgetconfusedwiththeisVoiceInteractionRoot()method,whichreturnstrueonlyiftheactivityisalsotherootofavoiceinteraction.Here,youwillgettrueifyouractivitywasstarteddirectlybythevoiceinteractionserviceandnotbyanotheractivity(anotherapp)whileundergoingvoiceinteraction.

Abestpracticewouldbetoprompttheusersandconfirmthatthisistheirintendedaction.YoualreadyknowthatvoiceinputisinvokedfromGoogleNow,whereyoucanopenURLswithasimplevoiceinput,suchasopenandroid.com.Now,youcaninventnewvoiceactionsandregisterthemwithGoogle,drivingtrafficdirectlyandspecificallytoyourapp.

Tolearnmoreaboutimplementingvoiceactions,headtohttps://developers.google.com/voice-actions/interaction/.

https://developers.google.com/voice-actions/interaction/

TheAssistAPIBackinGoogleI/O2015,wesawtheNowonTapfeature,whereGoogleNowcouldpeekintoarunningappandprovidecontextualassistance.TheAssistAPIoffersanewwayforuserstoengagethroughanassistant.Theassistantmustbeenabledpriortousingit,allowingittobeawareofthecurrentcontext.Triggeringtheassistantisdonebylong-pressingtheHomebutton,nomatterwhichappisactive.

YoucanoptoutofthisbysettingtheWindowManager.LayoutParams.FLAG_SECUREflag.

OptinginrequiresyoutousethenewAssistContentclass.

Inorderforustobeabletofeedadditionalcontextfromourapptotheassistant,weneedtofollowthesesteps:

1. ImplementtheApplication.OnProvideAssistDataListenerinterface,whichiscalledwhentheuserrequestsassistance.

2. RegisteritusingApplication.registerOnProvideAssistDataListener().3. OverridetheonProvideAssistData()callback,whichiscalledwhentheuser

requestsassistance.ItisusedtobuildanACTION_ASSISTintentwithallofthecontextofthecurrentapp.

4. OverridetheonProvideAssistContent()callback;thisisoptional.Itiscalledwhentheuserrequestsassistance,allowingustoprovidereferencestocontentrelatedtothecurrentactivity.

5. Whendone,unregisteryourselfusingApplication.unregisterOnProvideAssistDataListener().

BluetoothAPIChangesBesidesthechangesmentionedpreviously,AndroidMarshmallow6.0hasintroducedafewmorechangestotheBluetoothAPI.

BluetoothstylussupportStylushasbeenhereaforawhile;Bluetoothstylusdidn’thavefullsupportforspecificationsinversionsbeforeAndroidMarshmallow.YoucanpairandconnectacompatibleBluetoothstyluswitheitheraphoneoratablet.Becauseyouarenotboundjusttotouchesonscreen,youcanfusetheposition,pressure,andbuttonstatedata,allowingmorepreciseuserinputandexperience.Yourappcanaddalistenertothestylusbuttonsandactaccordingly.JustusetheView.OnContextClickListenerandGestureDetector.OnContextClickListenerobjectsinyouractivity.

Inordertodetectstylusbuttoninteractionsandmovement,youneedthefollowing:

TheMotionEventmethodsThegetTooltype()method,whichreturnsTOOL_TYPE_STYLUSifastyluswithabuttonistouchedonthescreenThegetButtonState()method,whichreturns(onAndroid6.0-targetedapps)thefollowing:

BUTTON_STYLUS_PRIMARY:PresstheprimarystylusbuttonBUTTON_STYLUS_SECONDARY:PressthesecondarybuttonBUTTON_STYLUS_PRIMARY|BUTTON_STYLUS_SECONDARY:Pressboththebuttons

TargetedappswithalowerAPIlevelthanAndroid6.0willresultinthefollowing:

BUTTON_SECONDARY:PresstheprimarystylusbuttonBUTTON_TERTIARY:PressthesecondarybuttonBUTTON_SECONDARY|BUTTON_TERTIARY:Pressboththebuttons

ImprovedBluetoothlowenergyscanningUsedtoBluetoothlowenergyinyourapp?Well,nowthescanningprocessiseasierandimproved.UsethenewsetCallbackType()methodandspecifythatyouwantacallbackwhenthesystemfinds/seesanadvertisementpacketmatchingtheScanFilterclass.Yougetmorepower-efficiencythaninpreviousAndroidversions.

SummaryWewentoverafewofthechangesinAndroidMarshmallow.Allofthesechangesareimportanttofollowandwillhelpyouinyourappdevelopmentcycles.Thereareafewmorechangestobediscussedinfuturechaptersinamoredetailedmanner.Ournextchaptertalksaboutaudio,video,andcamerafeaturesandthechangesmadeinAndroid6.0.6.

Chapter5.Audio,Video,andCameraFeaturesAndroidMarshmallowgivesusgoodaudio,video,andcameracapabilities,andyoucanseethatimprovementshavebeenmadetoenableandbettersupportnewormintconditionprotocolsorevenchangethebehaviorofsomeAPIs,suchasthecameraservice.

Inthischapter,wewilltryandexplainthesechangeswithaproperdiscussionontheirusageandbenefits.Ourjourneyintheupcomingpageswillcoverthefollowingtopics:

AudiofeaturesVideofeaturesCamerafeatures

AudiofeaturesAndroidMarshmallow6.0addssomeenrichmentstotheaudiofeaturesthatwewillcoverintheupcomingsections.

SupportfortheMIDIprotocolTheandroid.media.midipackagewasaddedinAndroid6.0(API23).

WiththenewmidiAPIs,youcannowsendandreceiveMIDI(shortforMusicalInstrumentDigitalInterface)eventsinamuchsimplerwaythanearlier.

Thepackagewasbuilttoprovideuswithcapabilitiestodothefollowing:

ConnectanduseaMIDIkeyboardConnecttootherMIDIcontrollersUseexternalMIDIsynthesizers,externalperipherals,lights,showcontrol,andsoonAllowdynamicmusicgenerationfromgamesormusic-creationappsAllowthecreationandpassingofMIDImessagesbetweenappsAllowAndroiddevicestoactasmulti-touchcontrollerswhenconnectedtoalaptop

WhendealingwithMIDI,youmustdeclareitinthemanifest,asfollows:

<uses-featureandroid:name="android.software.midi"

android:required="true"/>

Payattentiontotherequiredpart;inamannersimilartootherfeatures,settingittotruewillmakeyourappvisibleintheplaystoreonlyifthedevicesupportstheMIDIAPI.

YoucanalsocheckinruntimeforMIDIsupportandthenchangetherequiredparttofalse:

PackageManagerpkgMgr=context.getPackageManager();

if(pkgMgr.hasSystemFeature(PackageManager.FEATURE_MIDI)){

//wecanuseMIDIAPIhereasweknowthedevicesupportstheMIDIAPI.

}

MidiManagerAwaytoproperlyusetheMIDIAPIisviatheMidiManagerclass;obtainitviacontextanduseitwhenrequired:

MidiManagermidiMgr=

(MidiManager)context.getSystemService(Context.MIDI_SERVICE);

Formoreinformation,youcanreferto:

https://developer.android.com/reference/android/media/midi/package-summary.html

https://developer.android.com/reference/android/media/midi/package-summary.html

DigitalaudiocaptureandplaybackTwonewclasseshavebeenaddedfordigitalaudiocaptureandplayback:

android.media.AudioRecord.Builder-digitalaudiocaptureandroid.media.AudioTrack.Builder-digitalaudioplayback

Thesewillhelpconfiguretheaudiosourceandsinkproperties.

AudioandinputdevicesThenewhasMicrophone()methodhasbeenaddedtotheInputDeviceclass.Thiswillreportwhetherthedevicehasabuilt-inmicrophonethatdeveloperscanuse.Let’ssayyouwanttoenablevoicesearchfromacontrollerconnectedtoAndroidTVandyougetanonSearchRequested()callbackfortheuser’ssearch.Youcanthenverifythatthere’samicrophonewiththeinputDeviceobjectyougetinthecallback.

InformationonaudiodevicesThenewAudioManager.getDevices(intflags)methodallowseasyretrievalofalltheaudiodevicescurrentlyconnectedtothesystem.Ifyouwanttobenotifiedwhenthereareaudiodeviceconnections/disconnections,youcanregisteryourapptoanAudioDeviceCallbackcallbackviatheAudioManager.registerAudioDeviceCallback(AudioDeviceCallbackcallback,

Handlerhandler)method.

ChangesinAudioManagerSomechangeshavebeenintroducedintheAudioManagerclass,andtheyareasfollows:

UsingAudioManagertosetthevolumedirectlyisnotsupported.UsingAudioManagertomutespecificstreamsisnotsupported.TheAudioManager.setStreamSolo(intstreamType,booleanstate)methodisdeprecated.Ifyouneedexclusiveaudioplayback,useAudioManager.requestAudioFocus(AudioManager.OnAudioFocusChangeListener

l,intstreamType,intdurationHint).TheAudioManager.setStreamMute(intstreamType,booleanstate)methodisdeprecated.IfyouneedtouseAudioManager.adjustStreamVolume(intstreamType,intdirection,intflags)fordirection,youcanuseoneofthenewlyaddedconstants.ADJUST_MUTEwillmutethevolume.Notethatithasnoeffectifthestreamisalreadymuted.ADJUST_UNMUTEwillunmutethevolume.Notethatithasnoeffectifthestreamisnotmuted.

VideofeaturesInAndroidMarshmallow,thevideoprocessingAPIhasbeenupgradedwithnewcapabilities.Somenewmethodsandevenanewclasshasbeenaddedjustfordevelopers.

android.media.MediaSyncTheallnewMediaSyncclasshasbeendesignedtohelpuswithsynchronousaudioandvideostreams’rendering.Youcanalsouseittoplayaudio-orvideo-onlystreams.Youcanusethedynamicplaybackrateandfeedthebuffersinanonblockingactionwithacallbackreturn.Formoreinformationontheproperusage,read:

https://developer.android.com/reference/android/media/MediaSync.html

https://developer.android.com/reference/android/media/MediaSync.html

MediaCodecInfo.CodecCapabilities.getMaxSupportedInstancesNow,wehaveaMediaCodecInfo.CodecCapabilities.getMaxSupportedInstanceshelpermethodtogetthemaximumnumberofsupportedconcurrentcodecinstances.However,wemustconsiderthisonlyanupperbound.Theactualnumberofconcurrentinstancescanbelowerdependingonthedeviceandtheamountofavailableresourcesatthetimeofusage.

Whydoweneedtoknowthis?Let’sthinkofacasewherewehaveamedia-playingapplicationandwewanttoaddeffectsbetweenthemoviesplayed.Wewillneedtousemorethanonevideocodec,decodetwovideos,andencodeonevideostreambacktobedisplayedonscreen.CheckingwiththisAPIwillallowyoutoaddmorefeaturesthatrelyuponmultipleinstancesofcodecs.

MediaPlayer.setPlaybackParamsWecannowsetthemediaplaybackrateforfastorslowmotionplayback.Thiswillgiveusthechancetocreateafunnyvideoappwhereweslowdownpartsorplaythemfast,creatinganewvideowhileplaying.Audioplayingissyncedaccordingly,soyoumighthearapersontalkingslowlyorevenfast,forthatmatter.

CamerafeaturesInAndroidLollipop,therewasthenewCamera2API,andnow,inAndroidMarshmallow,thereareafewmoreupdatestothecamera,flashlight,andimagereprocessingfeatures.

TheflashlightAPIAlmosteverydevicetodayhasacamera,andalmosteverycameradevicehasaflashunit.ThesetTorchMode()methodhasbeenaddedtocontroltheflashtorchmode.

ThesetTorchMode()methodisusedinthefollowingmanner:

CameraManager.setTorchMode(StringcameraId,booleanenabled)

ThecameraIdelementistheuniqueIDfortheflashunitcamerawithwhichyouwanttochangethetorchmode.YoucanusegetCameraIdList()togetthelistofcamerasandthenusegetCameraCharacteristics(StringcameraId)tocheckwhetherflashissupportedinthatcamera.ThesetTorchMode()methodallowsyoutoturnitonoroffwithoutopeningthecameradeviceandwithoutrequestingpermissionfromthecamera.Thetorchmodewillbeswitchedoffassoonasthecameradevicebecomesunavailableorwhenothercameraresourcesthathavethetorchonbecomeunavailable.Otherappscanusetheflashunitaswell,soyouneedtocheckthemodewhenrequiredorregisteracallbackviatheregisterTorchCallback()method.

Refertothesampleapp,Torchi,toseetheentirecodeat:

https://github.com/MaTriXy/Torchi

NoteTurningonthetorchmodemayfailifthecameraorothercameraresourcesareinuse.

https://github.com/MaTriXy/Torchi

ThereprocessingAPIAsmentionedearlier,theCamera2APIwasgivenafewbooststoallowaddedsupportforYUVandprivateopaqueformatimagereprocessing.BeforeusingthisAPI,weneedtocheckwhetherthesecapabilitiesareavailable.ThisiswhyweusethegetCameraCharacteristics(StringcameraId)methodandcheckfortheREPROCESS_MAX_CAPTURE_STALLkey.

android.media.ImageWriterThisisanewclassthat’sbeenaddedtoAndroid6.0.

ItallowsustocreateanimageandfeeditintoasurfaceandthenbacktoCameraDevice.Usually,ImageWriterisusedalongwithImageReader.

android.media.ImageReaderThisisanewclassthat’sbeenaddedtoAndroid6.0.

Itallowsusdirectaccesstotheimagedatarenderedinasurface.ImageReader,alongwithImageWriter,allowsourapptocreateanimagefeedfromthecameratothesurfaceandbacktothecameraforreprocessing.

ChangesinthecameraserviceAndroidMarshmallowhasmadeachangetothefirstcome,firstserveaccessmodel;now,theserviceaccessmodelhasfavoritesprocesses—onesthataremarkedashigh-priority.Thischangeresultsinsomemorelogic-relatedworkforusdevelopers.Weneedtomakesurethatwetakeintoaccountasituationwherewegetbumpedup(higherpriority)ordebunked(lowerpriorityduetoachangeinourapplication).

Let’stryandexplainthisinafewsimplebullets:

Whenyouwanttoaccesscameraresourcesoropenandconfigureacameradevice,youraccessisverifiedaccordingtothepriorityofyourapplicationprocess.Anapplicationprocesswithforegroundactivities(visibleuser)isnormallygivenahigherpriority,whichinturnallowsabetterchancetogetthedesiredaccesswhenneeded.Ontheothersideofthepriorityscale,youcanfindlow-priorityappsthatcanandwillbetossedaside(revokedfromaccess)whenahigh-priorityapplicationattemptstousethecamera.Forexample,whenusingtheCameraAPI,youwillgettheonError()callwhenevicted,andwhenusingtheCamera2API,youwillgettheonDisconnected()callwhenevicted.Somedevicesoutinthewildcanallowseparateapplicationstoopenanduseseparatecameradevicessimultaneously.Thecameraservicenowdetectsanddisallowsperformanceissuesthatarecausedduetomultiprocessusage.Whentheservicedetectssuchanissue,itwillevictlow-priorityappsevenifonlyoneappisusingthatcameradevice.Inamultiuserenvironment,whenswitchingusers,allactiveappsusingthecameraintheprevioususerprofilewillbeevictedinordertoallowproperusageandaccesstoappsforthecurrentuser.Thismeansthatswitchinguserswillstopthecamera-usingappsfromusingthecameraforsure.

SummaryInthischapter,wecoveredquiteafewchangesinandadditionstotheAndroidAPIs.AndroidMarshmallowismoreabouthelpingus,thedevelopers,achievebettermediasupportandshowcaseourideaswhenusingtheaudio,video,orcameraAPIs.

Inthenextchapter,wewillgooversomeoftheAndroidfeaturestounderstandthefeatures,additions,andchangesmade.

Chapter6.AndroidforWorkMostofyouknowthatAndroiddeviceshaveahugemarketsharepercentageworldwide,andmoreandmorebusinessesarefollowingtheBYOD(shortforBringYourOwnDevice)policy.ThisisdonewiththehelpofAndroidforWork,aspecialprogramforcompanieswhereseveraladdedfeaturesintheAndroidplatformallowbettermobiledevicemanagement,administration,andintegrationwithinthecompany.

Whendealingwithenterprisesorevensmall-sizedandmedium-sizedbusinesses,youneedtofollowspecificguidelinesandharnesstheAndroidAPItoyourbenefit.YoucanreadmoreaboutAndroidforWorkat:

http://developer.android.com/training/enterprise/index.html

AndroidMarshmallowhasmadeafewchangestotheAndroidforWorkprogram,wherealotofthechangesweremadeforbetterandeasierusagefordevelopersaswellasworkusers.

Inthischapter,wewillcovertheAndroidMarshmallowchangesthatreflectorarerelateddirectlytoAndroidforWork:

BehavioralchangesSingle-usedeviceimprovementsSilentlyinstalling/uninstallingappsImprovedcertificateaccessAutomaticsystemupdatesThird-partycertificateinstallationDatausagestatisticsManagingruntimepermissionsVPNaccessanddisplayWorkprofilestatus

http://developer.android.com/training/enterprise/index.html

BehavioralchangesAndroidMarshmallowhasintroducedafewbehavioralchangesrelatedtoAndroidforWork.

TheworkprofilecontactsdisplayoptionUsingthefollowingsetting,youcannowdisplayyourworkprofilecontactsinthedialercalllog:

DevicePolicyManager.setCrossProfileCallerIdDisabled(ComponentNameadmin,

booleandisabled)

YoucanalsodisplaytheworkcontactsoverBluetoothwiththenewoption.Settingthistofalsewillallowthedisplay;thedefaultvalueistrue(disablingthecontact-sharingoption):

DevicePolicyManager.setBluetoothContactSharingDisabled(ComponentName

admin,booleandisabled)

Wi-FiconfigurationoptionsWhenaddingaWi-Finetworkviaaworkprofile,usually,addedconfigurationsstaypersistentevenaftertheprofileisdeleted.Now,allconfigurationsaddedbyaprofileownerareremovediftheworkprofileisdeleted.

TheWi-FiconfigurationlockAnewSettings.Globalsettinghasbeenadded:

WIFI_DEVICE_OWNER_CONFIGS_LOCKDOWN

Thissettingisanintegervaluesetting,whichmeansthatazerovalueorabsencewillleadtoallWi-Ficonfigurationsbeingmodifiedordeletedbytheuser.Settingtheintegervaluetoanonzerovaluewillinitiatethelock,whichmeansthattheusercan’tmodifyordeleteWi-Ficonfigurationscreatedbyadeviceowner—user-createdconfigurationswillstillbemodifiable.NotethatanactivedeviceownerhascompleteprivilegesinanyWi-Ficonfigurations,eventhosenotcreatedbythem.

WorkPolicyControlleradditionYoucancontinuetoaddGoogleaccountstothedevice,butnow,whenaddinganaccountthatismanagedbyWorkPolicyController,theflowischangedtoincludetheWorkPolicyControlleraddition.AnaddedaccountpromptstheusertoinstalltheappropriateWorkPolicyController.Thisisalsotruewhenaddinganaccountthroughsettingsorviathestartupdevice’ssetupwizard.FormoreinformationonhowtobuildaWorkPolicyController,read:

http://developer.android.com/training/enterprise/work-policy-ctrl.html

http://developer.android.com/training/enterprise/work-policy-ctrl.html

DevicePolicyManagerchangesInDevicePolicyManager,youmayencounterquiteafewchangesinbehavior;thesearelistedinthefollowingbulletswithashortexplanation:

setCameraDisabled()affectsthecamerajustforthecallinguser;iftheprofileisamanagedprofile,thenthecalldoesn’taffectthecameraappsrunningontheprimaryuser.setKeyguardDisabledFeatures()wasmadeavailableforprofileownersanddeviceowners.Profileownerscansetkeyguardrestrictionsviathefollowing:

KEYGUARD_DISABLE_TRUST_AGENTS:Thiswillignorethetrustagentstateonthekeyguardonsecurescreens(thePINcode,pattern,orthepasswordscreen)KEYGUARD_DISABLE_FINGERPRINT:Thiswilldisablethefingerprintsensoronthekeyguardonsecurescreens(PINcode,pattern,orthepasswordscreen)KEYGUARD_DISABLE_UNREDACTED_NOTIFICATIONS:Thiswillallowonlyredactednotificationsonsecurekeyguardscreensandonlynotificationsgeneratedbyapplicationsinthemanagedprofile

createAndInitializeUser()isdeprecatednow.createUser()isdeprecatednow.UsingthesetScreenCaptureDisabled()method,theAssistfeatureisblocked,butthishappensonlywhenanappofthegivenuserisintheforeground.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUMisSHA-256now.LegacysupportforSHA-1stillexists,butitwillberemovedinfutureversionsaccordingtothedocumentation.EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUMisSHA-256onlynow.EXTRA_PROVISIONING_RESET_PROTECTION_PARAMETERSwasremovedsothatNFCbumpprovisioningwouldnotunlockafactory-reset-protecteddevice.PassingdatatothedeviceownerduringNFCprovisioningcanbedonewithEXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE.NewDevicePolicyManagerAPIforpermissionsunderAndroidMarshmallow’snewpermissionmodel.YoucanreadmoreaboutDevicePolicyManagerathttps://developer.android.com/reference/android/app/admin/DevicePolicyManager.htmlRESULT_CANCELEDisnowreturnedifuserscancelthesetupflowinitiatedthroughanACTION_PROVISION_MANAGED_PROFILEorACTION_PROVISION_MANAGED_DEVICEintent.ChangestoSettings.Global.DisabledthefollowingsetofsettingsviasetGlobalSettings():

BLUETOOTH_ON

DEVELOPMENT_SETTINGS_ENABLED

MODE_RINGER

NETWORK_PREFERENCE

WIFI_ON

EnabledtheWIFI_DEVICE_OWNER_CONFIGS_LOCKDOWNsettingvia

https://developer.android.com/reference/android/app/admin/DevicePolicyManager.html

setGlobalSettings().

Single-usedeviceimprovementsYouasthedeviceownercannowcontroladdedsettings,thusimprovingdevicemanagementusingthefollowing:

setKeyguardDisabled()canbeusedtodisableorre-enablethekeyguardsetStatusBarDisabled()canbeusedtodisableorre-enablethestatusbarUserManager.DISALLOW_SAFE_BOOTisanewconstantthatstateswhethertheusercanbootadevicetosafebootSettings.Global.STAY_ON_WHILE_PLUGGED_INwillpreventthescreenfromturningoffwhilepluggedintopower

Silentlyinstalling/uninstallingappsNow,youcansilentlyinstallanduninstallapplicationsusingPackageInstallerAPIs.Thismeansinstallingappswithoutuserinteractionorevenremovingappsaspartofthecompanypolicy.ThisfeatureenablesyoutousedeviceswithoutactuallyactivatingaGoogleaccount.GooglePlayforWorkisnotrequired,allowingyoutousedevicesaskiosks,showcasingspecificappsnotreleasedyet,andsoon.

ImprovedcertificateaccessAllowinguserstograntmanagedapps’accesstocertificateswithoutuserinteractionwasnotpossiblepriortoAndroidMarshmallow,sonow,anewcallbackhasbeenadded:

DeviceAdminReceiver.onChoosePrivateKeyAlias(Contextcontext,Intent

intent,intuid,Uriuri,Stringalias)

Thiscallbackwillallowthedeviceownertoprovidethealiassilentlytotherequestingapplication.

AutomaticsystemupdatesThefollowingoptionhasbeenaddedinAndroid6.0anditsmainpurposeistoallowdeviceownerstoauto-acceptasystemupdate:

DevicePolicyManager.setSystemUpdatePolicy(ComponentNameadmin,

SystemUpdatePolicypolicy)

SystemUpdatePolicyhasbeenaddedaswell,andyoucanchoosefromthreeoptions:

TYPE_INSTALL_AUTOMATIC:updateassoonasyougetanupdateTYPE_INSTALL_WINDOWED:updateshouldbedonewithinatimedsystemmaintenanceandonlythen,justfor30daysandthenreturntonormalbehaviorTYPE_POSTPONE:postponeupdatesforupto30daysandthenreturntonormalbehaviorafterwards

Thiscancomeinhandyifyouhavedevicessuchasshowcasetabletsorkioskmodedevices,wheretheupdateshouldnotmesswiththedevices’work.

Third-partycertificateinstallationThird-partyappsnowhavetheabilitytocallDevicePolicyManagerAPIs:

getInstalledCaCerts()

hasCaCertInstalled()

installCaCert()

uninstallCaCert()

uninstallAllUserCaCerts()

installKeyPair()

TheseAPIcallscanonlybedoneifthepermissionhasbeengrantedbythedeviceownerorprofileowner.

DatausagestatisticsAnewclasshasbeenaddedinAndroid6.0:NetworkStatsManager.ThishelpsyouqueryfordatausagestatisticsthatcanbeseeninSettings|Datausage.

Accessforprofileownersisautomaticallygrantedinorderforthemtoquerydataontheirprofile.Deviceownersgetaccesstothedatausageofthemanagedprimaryuser.

NoteTheandroid.app.usage.NetworkUsageStatsclasshasbeenrenamedtoNetworkStats.

ManagingruntimepermissionsAndroidMarshmallowintroducedtheruntimepermissionsmodel,andAndroidforWorkhadtodealwithmanagingpoliciesfordevices.YouasdeviceownercannowsetapolicyforallruntimerequestsofallapplicationsusingsetPermissionPolicy().

Youcanchoosetopromptuserstograntpermissionsorautomaticallygrantordenythepermissionssilently.Theautomaticpolicymeansthattheusercannotmodifytheapp’spermissionsscreeninSettings.

VPNaccessanddisplayWhenheadingtoSettings|More|VPN,youcannowviewtheVPNapps.WhenusingVPN,thenotificationsshownarenowspecifictohowthatVPNisconfigured:

Theprofileowner:NotificationsareshownaccordingtotheVPNconfigurationandbasedontheprofile(personal,work,orboth)Thedeviceowner:NotificationsareshownwhentheVPNisconfiguredfortheentiredevice

WorkprofilestatusTwonewadditionswereintroducedfortheuserstoknowthattheyareunderadifferentprofile:

Whenusinganappfromaworkprofile,thestatusbarwilldisplayabriefcaseiconWhenunlockingadevicestraightfromaworkprofileapp,apopupisdisplayed,alertingtheuserthatthisapprunsontheworkprofile

SummaryAswesawinthischapter,AndroidMarshmallowhasbroughtinquiteafewchangestotheAndroidforWorkworld.Asdevelopers,weneedtoalwaysmaintainaviableconnectiontotheneedsofanorganization.WeneedtomakesurewegooverandunderstandtheAndroidforWorkworld;thechangesinMarshmallowhelpusbuildandtargetenterpriseworkflowswiththebenefitofasimplerAPI.

Inthenextchapter,wewilllearnabouttheChromecustomtabsAPI’susageandflow.

Chapter7.ChromeCustomTabsHaveyoueverwantedtoaddaWebViewtoyourapplication?Maybeyou’vewantedtoaddbrowsingforafewwebpagesandshowsomerelevantcontentfromwithinyourapplication?IknowIhadto.Onalmosteveryoccasion,IwasreluctanttousetheWebViewfeatureasthiswasoneoftheugliestpartsoftheapp.

YoucanclearlyseethattheWebViewfeatureisawebportionandtheUIwasaddedquiteafewAndroidversionsback,whichcausedmyOCDUI/UXsensegokaboom.OneofthenewestadditionsreleasedbyGooglewasChromecustomtabs.

Inthischapter,wewillexploreChromecustomtabsandtrytoexplainanddemonstratethebenefitsofusingitinsteadoftheplainoldWebView:

WhatisaChromecustomtab?WhentouseChromecustomtabsTheimplementationguide

WhatisaChromecustomtab?Well,mostofusknowtabsfromeverydayInternetbrowsing.Itdoesn’treallymatterwhichbrowseryouuse;allbrowserssupporttabsandmultipletabs’browsing.Thisallowsustohavemorethanonewebsiteopenatthesametimeandnavigatebetweentheopenedinstances.InAndroid,thingsaremuchthesame,butwhenusingWebView,youdon’thavetabs.

WhatisWebView?WebViewisthepartintheAndroidOSthat’sresponsibleforrenderingwebpagesinmostAndroidapps.IfyouseewebcontentinanAndroidapp,chancesareyou’relookingatWebView.ThemajorexceptionstothisrulearesomeoftheAndroidbrowsers,suchasChrome,Firefox,andsoon.

InAndroid4.3andlower,WebViewusescodebasedonApple’sWebkit.InAndroid4.4andhigher,WebViewisbasedontheChromiumproject,whichistheopensourcebaseofGoogleChrome.InAndroid5.0,WebViewwasdecoupledintoaseparateappthatallowedtimelyupdatesthroughGooglePlaywithoutrequiringfirmwareupdatestobeissued,andthesametechniquewasusedwithGooglePlayservices.

Now,let’stalkagainaboutasimplescenario:wewanttodisplaywebcontent(URL-related)inourapplication.Wehavetwooptions:eitherlaunchabrowserorbuildourownin-appbrowserusingWebView.Bothoptionshavetrade-offsordisadvantagesifwewritethemdown.Abrowserisanexternalapplicationandyoucan’treallychangeitsUI;whileusingit,youpushtheuserstootherappsandyoumaylosetheminthewild.Ontheotherhand,usingWebViewwillkeeptheuserstightlyinside.However,actuallydealingwithallpossibleactionsinWebViewisquiteanoverhead.

GoogleheardourrantandcametotherescuewithChromecustomtabs.Nowwehavebettercontroloverthewebcontentinourapplication,andwecanstitchwebcontentintoourappinacleaner,prettiermanner.

CustomizationoptionsChromecustomtabsallowseveralmodificationsandtweaks:

ThetoolbarcolorEnterandexitanimationsCustomactionsforthetoolbarandoverflowmenuPrestartedandprefetchedcontentforfasterloading

WhentouseChromecustomtabsEversinceWebViewcameout,applicationshavebeenusingitinmultipleways,embeddingcontent—localstaticcontentinsidetheAPKanddynamiccontentasloadingwebpagesthatwerenotdesignedformobiledevicesatthebeginning.Lateronwesawtheriseofthemobileweberacompletewithhybridapplications).

Chromecustomtabsareabitmorethanjustloadinglocalcontentormobile-compatiblewebcontent.Theyshouldbeusedwhenyouloadwebdataandwanttoallowsimpleimplementationandeasiercodemaintenanceand,furthermore,makethewebcontentpartofyourapplication—asifit’salwaystherewithinyourapp.

Amongthereasonswhyyoushouldusecustomtabsarethefollowing:

Easyimplementation:youusethesupportlibrarywhenrequiredorjustaddextrastoyourViewintent.It’sthatsimple.InappUImodifications,youcandothefollowing:

SetthetoolbarcolorAdd/changetheactionbuttonAddcustommenuitemstotheoverflowmenuSetandcreatecustomin/outanimationswhenenteringthetaborexitingtothepreviouslocation

Easiernavigationandnavigationlogic:youcangetacallbacknotifyingyouaboutanexternalnavigation,ifrequired.Youknowwhentheusernavigatestowebcontentandwheretheyshouldreturnwhendone.Chromecustomtabsallowaddedperformanceoptimizationsthatyoucanuse:

Youcankeeptheenginerunning,sotospeak,andactuallygivethecustomtabaheadstarttostartitselfanddosomewarmuppriortousingit.Thisisdonewithoutinterferingortakingawaypreciousapplicationresources.YoucanprovideaURLtoloadinadvanceinthebackgroundwhilewaitingforotheruserinteractions.Thisspeedsuptheuser-visiblepageloadingtimeandgivestheuserasenseofblazingfastapplicationwhereallthecontentisjustaclickaway.

Whileusingthecustomtab,theapplicationwon’tbeevictedastheapplicationlevelwillstillbeintheforegroundeventhoughthetabisontopofit.So,weremainatthetoplevelfortheentireusagetime(unlessaphonecallorsomeotheruserinteractionleadstoachange).UsingthesameChromecontainermeansthatusersarealreadysignedintositestheyconnectedtointhepast;specificpermissionsthatweregrantedpreviouslyapplyhereaswell;evenfilldata,autocomplete,andsyncworkhere.Chromecustomtabsallowusgivetheusersthelatestbrowserimplementationonpre-LollipopdeviceswhereWebViewisnotthelatestversion.

TheimplementationguideAsdiscussedearlier,wehaveacoupleoffeaturesintegratedintoChromecustomtabs.ThefirstcustomizestheUIandinteractionwiththecustomtabs.Thesecondallowspagestobeloadedfasterandkeepstheapplicationalive.

CanweuseChromecustomtabs?Beforewestartusingcustomtabs,wewanttomakesurethey’resupported.Chromecustomtabsexposeaservice,sothebestcheckforsupportistotryandbindtotheservice.Successmeansthatcustomtabsaresupportedandcanbeused.Youcancheckoutthisgist,whichshowsahelperhowtotocheckit,orchecktheprojectsourcecodelateronat:

https://gist.github.com/MaTriXy/5775cb0ff98216b2a99d

Aftercheckingandlearningthatsupportexists,wewillstartwiththeUIandinteractionpart.

https://gist.github.com/MaTriXy/5775cb0ff98216b2a99d

CustomUIandtabinteractionHere,wewillusethewell-knownACTION_VIEWintentaction,andbyappendingextrastotheintentsenttoChrome,wewilltriggerchangesintheUI.RememberthattheACTION_VIEWintentiscompatiblewithallbrowsers,includingChrome.TherearesomephoneswithoutChromeoutthere,orthereareinstanceswherethedevice’sdefaultbrowserisn’tChrome.Inthesecases,theuserwillnavigatetothespecificbrowserapplication.

IntentisaconvenientwaytopassthatextradatawewantChrometoget.

Don’tuseanyoftheseflagswhencallingtotheChromecustomtabs:

FLAG_ACTIVITY_NEW_TASK

FLAG_ACTIVITY_NEW_DOCUMENT

BeforeusingtheAPI,weneedtoaddittoourgradlefile:

compile'com.android.support:customtabs:23.1.0'

Thiswillallowustousethecustomtabsupportlibraryinourapplication:

CustomTabsIntent.EXTRA_SESSION

Theprecedingcodeisanextrafromthecustomtabssupportlibrary;it’susedtomatchthesession.Itmustbeincludedintheintentwhenopeningacustomtab.Itcanbenullifthereisnoneedtomatchanyservice-sidesessionswiththeintent.

NoteWehaveasampleprojecttoshowtheoptionsfortheUIcalledChubbyTabbyathttps://github.com/MaTriXy/ChubbyTabby.

Wewillgoovertheimportantpartshereaswell.OurmaininteractioncomesfromaspecialbuilderfromthesupportlibrarycalledCustomTabsIntent.Builder;thisclasswillhelpusbuildtheintentweneedforthecustomtab:

CustomTabsIntent.BuilderintentBuilder=newCustomTabsIntent.Builder();

//initourBuilder

//SettingToolbarColor

intcolor=getResources().getColor(R.color.primary);

//weuseprimarycolorforourtoolbaraswell-youcandefineanycolor

youwantanduseit.

intentBuilder.setToolbarColor(color);

//EnablingTitleshowing

intentBuilder.setShowTitle(true);

//thiswillshowthetitleinthecustomtabalongtheurlshowingatthe

bottompartofthetabtoolbar.

//Thispartisaddingcustomactionstotheoverflowmenu

https://github.com/MaTriXy/ChubbyTabby

StringmenuItemTitle=getString(R.string.menu_title_share);

PendingIntentmenuItemPendingIntent=createPendingShareIntent();

intentBuilder.addMenuItem(menuItemTitle,menuItemPendingIntent);

StringmenuItemEmailTitle=getString(R.string.menu_title_email);

PendingIntentmenuItemPendingIntentTwo=createPendingEmailIntent();

intentBuilder.addMenuItem(menuItemEmailTitle,menuItemPendingIntentTwo);

//SettingcustomCloseIcon.

intentBuilder.setCloseButtonIcon(mCloseButtonBitmap);

//Addingcustomiconwithcustomactionfortheshareaction.

intentBuilder.setActionButton(mActionButtonBitmap,

getString(R.string.menu_title_share),createPendingShareIntent());

//Settingstartandexitanimationforthecustomtab.

intentBuilder.setStartAnimations(this,R.anim.slide_in_right,

R.anim.slide_out_left);

intentBuilder.setExitAnimations(this,android.R.anim.slide_in_left,

android.R.anim.slide_out_right);

CustomTabActivityHelper.openCustomTab(this,intentBuilder.build(),

Uri.parse(URL),newWebviewFallback(),useCustom);

Afewthingstonoticehereareasfollows:

Everymenuitemusesapendingintent;ifyoudon’tknowwhatapendingintentis,headto:

http://developer.android.com/reference/android/app/PendingIntent.html

Whenwesetcustomicons,suchasclosebuttonsoranactionbutton,forthatmatter,weusebitmapsandwemustdecodethebitmappriortopassingittothebuilderSettinganimationsiseasyandyoucanuseanimations’XMLfilesthatyoucreatedpreviously;justmakesurethatyoutesttheresultbeforereleasingtheapp

ThefollowingscreenshotisanexampleofaChromecustomtab:

http://developer.android.com/reference/android/app/PendingIntent.html

ThecustomactionbuttonAsdevelopers,wehavefullcontrolovertheactionbuttonspresentedinourcustomtab.Formostusecases,wecanthinkofashareactionormaybeamorecommonoptionthatyouruserswillperform.TheactionbuttonisbasicallyabundlewithaniconoftheactionbuttonandapendingintentthatwillbecalledbyChromewhenyouruserhitstheactionbutton.Theiconshouldbe24dpinheightand24-48dpinwidthaccordingtospecifications.

//Addingcustomiconwithcustomactionfortheshareaction

intentBuilder.setActionButton(mActionButtonBitmap,

getString(R.string.menu_title_share),createPendingShareIntent());

ConfiguringacustommenuBydefault,Chromecustomtabsusuallyhaveathree-iconrowwithForward,PageInfo,andRefreshontopatalltimesandFindinpageandOpeninBrowser(OpeninChromecanappearaswell)atthefooterofthemenu.

We,developers,havetheabilitytoaddandcustomizeuptothreemenuitemsthatwill

appearbetweentheiconrowandfootitemsasshowninthefollowingscreenshot:

Themenuweseeisactuallyrepresentedbyanarrayofbundles,eachwithmenutextandapendingintentthatChromewillcallonourbehalfwhentheusertapstheitem:

//Thispartisaddingcustombuttonstotheoverflowmenu

StringmenuItemTitle=getString(R.string.menu_title_share);

PendingIntentmenuItemPendingIntent=createPendingShareIntent();

intentBuilder.addMenuItem(menuItemTitle,menuItemPendingIntent);

StringmenuItemEmailTitle=getString(R.string.menu_title_email);

PendingIntentmenuItemPendingIntentTwo=createPendingEmailIntent();

intentBuilder.addMenuItem(menuItemEmailTitle,menuItemPendingIntentTwo);

ConfiguringcustomenterandexitanimationsNothingiscompletewithoutafewanimationstotagalong.Thisisnodifferent,aswehavetwotransitionstomake:oneforthecustomtabtoenterandanotherforitsexit;wehavetheoptiontosetaspecificanimationforeachstartandexitanimation:

//Settingstartandexitanimationforthecustomtab.

intentBuilder.setStartAnimations(this,R.anim.slide_in_right,

R.anim.slide_out_left);

intentBuilder.setExitAnimations(this,android.R.anim.slide_in_left,

android.R.anim.slide_out_right);

Chromewarm-upNormally,afterwefinishsettinguptheintentwiththeintentbuilder,weshouldcallCustomTabsIntent.launchUrl(Activitycontext,Uriurl),whichisanonstaticmethodthatwilltriggeranewcustomtabactivitytoloadtheURLandshowitinthecustomtab.Thiscantakeupquitesometimeandimpacttheimpressionofsmoothnesstheappprovides.

Weallknowthatusersdemandanear-instantaneousexperience,soChromehasaservicethatwecanconnecttoandaskittowarmupthebrowseranditsnativecomponents.CallingthiswillaskChrometoperformthefollowing:

TheDNSpreresolutionoftheURL’smaindomainTheDNSpreresolutionofthemostlikelysubresourcesPreconnectiontothedestination,includingHTTPS/TLSnegotiation

TheprocesstowarmupChromeisasfollows:

1. Connecttotheservice.2. Attachanavigationcallbacktogetnotifieduponfinishingthepageload.3. Ontheservice,callwarmuptostartChromebehindthescenes.4. CreatenewSession;thissessionisusedforallrequeststotheAPI.5. TellChromewhichpagestheuserislikelytoloadwithmayLaunchUrl.6. LaunchtheintentwiththesessionIDgeneratedinstep4.

ConnectingtotheChromeserviceConnectingtotheChromeserviceinvolvesdealingwithAndroidInterfaceDefinitionLanguage(AIDL).

Ifyoudon’tknowaboutAIDL,read:

http://developer.android.com/guide/components/aidl.html

TheinterfaceiscreatedwithAIDL,anditautomaticallycreatesaproxyserviceclassforus:

CustomTabsClient.bindCustomTabsService()

So,wecheckfortheChromepackagename;inoursampleproject,wehaveaspecialmethodtocheckwhetherChromeispresentinallvariations.Afterwesetthepackage,webindtotheserviceandgetaCustomTabsClientobjectthatwecanuseuntilwe’redisconnectedfromtheservice:

pkgName-Thisisoneofseveraloptionscheckingtoseeifwehavea

versionofChromeinstalledcanbeoneofthefollowing

staticfinalStringSTABLE_PACKAGE="com.android.chrome";

staticfinalStringBETA_PACKAGE="com.chrome.beta";

staticfinalStringDEV_PACKAGE="com.chrome.dev";

http://developer.android.com/guide/components/aidl.html

staticfinalStringLOCAL_PACKAGE="com.google.android.apps.chrome";

privateCustomTabsClientmClient;

//Bindstotheservice.

CustomTabsClient.bindCustomTabsService(myContext,pkgName,new

CustomTabsServiceConnection(){

@Override

publicvoidonCustomTabsServiceConnected(ComponentNamename,

CustomTabsClientclient){

//CustomTabsClientshouldnowbevalidtouse

mClient=client;

}

@Override

publicvoidonServiceDisconnected(ComponentNamename){

//CustomTabsClientisnolongervalidwhichalsoinvalidatessessions.

mClient=null;

}

});

Afterwebindtotheservice,wecancallthepropermethodsweneed.

WarmingupthebrowserprocessThemethodforthisisasfollows:

booleanCustomTabsClient.warmup(longflags)

//Withourvalidclientearlierwecallthewarmupmethod.

mClient.warmup(0);

NoteFlagsarecurrentlynotbeingused,sowepass0fornow.

Thewarm-upprocedureloadsnativelibrariesandthebrowserprocessrequiredtosupportcustomtabbrowsinglateron.Thisisasynchronous,andthereturnvalueindicateswhethertherequesthasbeenacceptedornot.Itreturnstruetoindicatesuccess.

CreatinganewtabsessionThemethodforthisisasfollows:

booleanCustomTabsClient.newSession(ICustomTabsCallbackcallback)

ThenewtabsessionisusedasthegroupingobjecttyingthemayLaunchUrlcall,theVIEWintentthatwebuild,andthetabgeneratedaltogether.WecangetacallbackassociatedwiththecreatedsessionthatwouldbepassedforanyconsecutivemayLaunchUrlcalls.ThismethodreturnsCustomTabsSessionwhenasessioniscreatedsuccessfully;otherwise,itreturnsNull.

SettingtheprefetchingURLThemethodforthisisasfollows:

booleanCustomTabsSession.mayLaunchUrl(Uriurl,Bundleextras,

List<Bundle>otherLikelyBundles)

ThismethodwillnotifythebrowserthatanavigationtothisURLwillhappensoon.Makesuretowarmup()priortocallingthismethod–thisisamust.ThemostlikelyURLhastobespecifiedfirst,andwecansendanoptionallistofotherlikelyURLs(otherLikelyBundles).Thelisthavetobesortedinadescendingorderandtheoptionallistmaybeignored.AnewcalltothismethodwilllowerthepriorityofpreviouscallsandcanresultinURLsnotbeingprefetched.Booleanvaluesinformuswhethertheoperationhasbeencompletedsuccessfully.

CustomtabsconnectioncallbackThemethodforthisisasfollows:

voidCustomTabsCallback.onNavigationEvent(intnavigationEvent,Bundle

extras)

Wehaveacallbacktriggereduponeachnavigationeventinthecustomtab.TheintnavigationEventelementisoneofthesixthatdefinesthestatethepageisin.Refertothefollowingcodeformoreinformation:

//Sentwhenthetabhasstartedloadingapage.

publicstaticfinalintNAVIGATION_STARTED=1;

//Sentwhenthetabhasfinishedloadingapage.

publicstaticfinalintNAVIGATION_FINISHED=2;

//Sentwhenthetabcouldn'tfinishloadingduetoafailure.

publicstaticfinalintNAVIGATION_FAILED=3;

//Sentwhenloadingwasabortedbyauseraction.

publicstaticfinalintNAVIGATION_ABORTED=4;

//Sentwhenthetabbecomesvisible.

publicstaticfinalintTAB_SHOWN=5;

//Sentwhenthetabbecomeshidden.

publicstaticfinalintTAB_HIDDEN=6;

privatestaticclassNavigationCallbackextendsCustomTabsCallback{

@Override

publicvoidonNavigationEvent(intnavigationEvent,Bundleextras){

Log.i(TAG,"onNavigationEvent:Code="+navigationEvent);

}

}

SummaryWelearnedaboutanewlyaddedfeature,Chromecustomtabs,whichallowsustoembedwebcontentintoourapplicationandmodifytheUI.Chromecustomtabsallowustoprovideafuller,fasterin-appwebexperienceforourusers.WeusetheChromeengineunderthehood,whichallowsfasterloadingthanregularWebViewsorloadingtheentireChrome(oranotherbrowser)application.

Wesawthatwecanpreloadpagesinthebackground,makingitappearasifourdataisblazingfast.WecancustomizethelookandfeelofourChrometabsothatitmatchesourapp.Amongthechangeswesawwerethetoolbarcolor,transitionanimations,andeventheadditionofcustomactionstothetoolbar.

CustomtabsalsobenefitfromChromefeaturessuchassavedpasswords,autofill,taptosearch,andsync;theseareallavailablewithinacustomtab.Fordevelopers,integrationisquiteeasyandrequiresonlyafewextralinesofcodeinthebasiclevel.Thesupportlibraryhelpswithmorecomplexintegration,ifrequired.

ThisisaChromefeature,whichmeansyougetitonanyAndroiddevicewherethelatestversionsofChromeareinstalled.RememberthattheChromecustomtabsupportlibrarychangeswithnewfeaturesandfixes,whichisthesameasothersupportlibraries,sopleaseupdateyourversionandmakesurethatyouusethelatestAPItoavoidanyissues.

Inournextchapter,wewilltakeadeepbreathandlookatsomeofthenewauthentication/securityfeaturesAndroidMarshmallowhastooffer.

Chapter8.AuthenticationAndroidMarshmallowhasintroducedanewlyintegratedAPItobettersupportuserauthenticationanduserverification.WecannowusethenewFingerprintAPIfordeviceswithafingerprintscannerinordertoauthenticatetheuser.Wecanalsosetaspecifictimeforuserlockscreenverificationtobeconsideredvalidintheapplogin.Inthischapter,wewilltryandgoovertheseadditionsandexplainhowtousethem:

TheFingerprintauthenticationAPICredentials’GracePeriodCleartextnetworktraffic

TheFingerprintauthenticationAPIAndroidMarshmallownowallowsus,thedevelopers,toauthenticateuserswiththeirfingerprintscanswhenusingsuchauthenticationscannersonsupporteddevices.

TheFingerprintAPIwasaddedtoAndroidMarshmallowviaawholenewpackage:android.hardware.fingerprint

Thepackagecontainsfourclasses:

FingerprintManager

FingerprintManager.AuthenticationCallback

FingerprintManager.AuthenticationResult

FingerprintManager.CryptoObject

Eachclasshasaspecificroleinourfingerprintauthenticationprocess.

Howdoweusefingerprintauthentication?Theprecedingfourclassesoftheandroid.hardware.fingerprintpackagecanbeexplainedinthefollowingmanner:

FingerprintManager:ManageaccesstofingerprinthardwareFingerprintManager.AuthenticationCallback:CallbackusedintheauthprocessFingerprintManager.AuthenticationResult:ResultcontainerforauthprocessFingerprintManager.CryptoObject:SpecificCryptoobjecttousewithFingerprintManager

Say,wewanttoauthenticateusersviatheirfingerprints.Adevicewithafingerprintsensormustbeinuse;otherwise,wecan’tusethisAPI.WeneedtogetaninstanceofFingerprintManager,andthenwecalltheauthenticate()method.Wemustimplementaspecificuserinterfaceforthefingerprintauthenticationflow,andthestandardAndroidfingerprinticon(c_fp_40px.png)isincludedinthesource.Weneedtoaddtheappropriatepermissiontoourapp’smanifest:

<uses-permissionandroid:name="android.permission.USE_FINGERPRINT"/>

Rightnow,wedon’thaveadevicewithafingerprintsensor,sowewillneedtotestourcodefromanemulator.(Nexus5XandNexus6Parestillwithlimitedsupply)

SettingupfortestingAndroidSDKToolsRevision24.3(atleast)mustbeinstalled.Now,wenavigatetoSettings|Security|Fingerprintandaddonefingerprint.

Followtheinstructionsmanually;weareaskedtoselectthePINandleadingustofindthefollowingscreenshot:

Finally,wemustuseaspecialadbcommand,trickingthesensorintocapturingamockfingerprint:

adb-eemufingertouch<finger_id>

Theresultantscreenshouldlooklikethefollowingscreenshot:

Weusedfinger_id=1forasinglefinger.Thesamecommandalsoemulatesfingerprinttoucheventsonthelockscreenorinourapp.

Ifyouneedhelptosetupanemulator,read:

https://developer.android.com/tools/devices/index.html

Now,wecanlaunchourapplicationandseethatwecanusethefingerprintasourauthenticationmethodwhentheuserpurchasesanitem.

https://developer.android.com/tools/devices/index.html

Credentials’GracePeriodEvergottheitchwhenyouwantedtouseanappafterdeviceunlockonlytofindthatyouneedtologinagainorentertheapppasswordagain?Well,nowwecanquerythedeviceandcheckwhetheritwasunlockedrecentlyandhowrecentwasit.Thiswillgiveourusersachancetoavoidallthefussthatcomeswithusingourapp.Notethatthismustbeusedinconjunctionwithapublicorsecretkeyimplementationforuserauthentication.IfyouwanttoreadmoreabouttheAndroidKeystoreSystem,headtohttps://developer.android.com/training/articles/keystore.html.

WeuseKeyguardManagerandcheckwhetherourlockscreenissecuredviatheisKeyguardSecure()method.Onceweknowthatit’ssecured,wecantryandusethefeature;otherwise,it’dimplythattheuserdidn’tsetasecurelockscreenandthisfeatureisano-op.

WegenerateasymmetrickeywithKeyGeneratorinAndroidKeyStore,whichcanonlybeusedaftertheuserhasauthenticatedwithdevicecredentialswithinthelastxseconds.Settingthisvalue(x)isdoneviathesetUserAuthenticationValidityDurationSeconds()method,whenwesetupKeyGeneratororKeyPairGenerator.

Youcancheckoutthesamplecodeformoreinformation.TheactivityiscalledCredGraceActivity.

NoteTryanddisplaythereauthenticationdialogaslessaspossible.Whenusingacryptographicobject,youshouldtryandverifyitsexpiry,andonlyifitpasses,usecreateConfirmDeviceCredentialIntent()toreauthenticatetheuser.

https://developer.android.com/training/articles/keystore.html

CleartextnetworktrafficAndroidMarshmallowalsoaddedanewflagtothemanifest.ThisflagindicateswhethertheapplicationisusingacleartextnetworktrafficsuchasHTTP.Theflagisandroid:usesCleartextTraffic,andthedefaultvalueistrue.SettingthistofalsemeansthatsomesystemAPIcomponents—suchasHTTPandFTPstacks,DownloadManagerandMediaPlayer—willrefusetoissueHTTPtrafficandwillonlyallowHTTPS.Itwouldbeagoodpracticetobuildathird-partylibrarythathonorthissettingaswell.Whyisthisgood?Well,cleartexttrafficlacksconfidentiality,authenticity,andprotectionsagainsttampering,anddatacanbetemperedwithoutitbeingdetected.Thisisamajorriskforapplications,andwecannowuseittotryandenforceastrongerandmoresecuredatatransportto/fromourapplications.

Weneedtorememberthatthisflagishonoredonthebasisofthebesteffort,andit’snotpossibletopreventallcleartexttrafficfromAndroidapplicationsgiventhattheyhavepermissionstousetheSocketAPI,forinstance,wheretheSocketAPIcannotdeterminecleartextusage.WecancheckoutthisflagbyreadingitfromeitherApplicationInfo.flagsorNetworkSecurityPolicy.isCleartextTrafficPermitted().

NoteWebViewdoesnothonorthisflag,whichmeansthatitwillloadHTTPeveniftheflagisfalse.

So,whatdowedowiththecleartextnetworktrafficflag?Duringappdevelopment,wecanuseStrictModeandidentifyanycleartexttrafficfromourappusingStrictMode.VmPolicy.Builder.detectCleartextNetwork().

ThedownsideofusesCleartextTrafficisthatitcausesappcrashesorprocessterminationwhenit’snotusingSSL(shortforSecureSocketLayer).Thisisgreatintheorybutnotinproduction,whereyourSSLcertificate,forsomereason,hasissuesandyoureroutethetraffictoHTTP.So,payextraattentiontowhereHTTPSisusedinyourappandwhereit’sokaytouseHTTP.

Luckily,wehaveStrictMode,whichnowhasawaytowarnyouifyourapplicationexecutesanyunencryptednetworkoperationsviaadetectCleartextNetwork()methodonStrictMode.VmPolicy.Builder.Inoursampleproject,wehaveaClearTextNetworkUsageActivityactivity;whenrunningtheTestStrictHttpproductFlavorvariant,youwillseethisinLogCat.

SummaryAndroidMarshmallowgaveusanewAPItoauthenticateuserswiththeFingerprintAPI.Wecanusethesensor,authenticatetheuserevenwithinourapplication,andsaveitforlateruseifwewanttosavetheneedforuserloginusingtheCredentials’GracePeriodcapabilitiesAndroidMarshmallowintroduced.

WealsocoveredawaytomakeourapplicationmoresecureusingHTTPSonly,andtheStrictModepolicy,enforcedwiththehelpoftheusesCleartextTrafficflag,whichallowsustomakesurethatallthenodesweconnecttotheouterworldandexaminetheneedforareasecureconnectionornot.

Iwouldliketothankyouforreading.

IwouldliketothanktheAndroidteam.Thisproducthaschangedmylife.

TheAndroidecosystemhasgreatdeveloperscontributingbypublishinglibraries,writingblogpostsandansweringsupportquestions;I’mproudtobepartofit.

Lookingforwardforfutureeditions.

IndexA

android.hardware.fingerprintpackageclasses/TheFingerprintauthenticationAPIFingerprintManager/Howdoweusefingerprintauthentication?FingerprintManager.AuthenticationCallback/Howdoweusefingerprintauthentication?FingerprintManager.AuthenticationResult/Howdoweusefingerprintauthentication?FingerprintManager.CryptoObject/Howdoweusefingerprintauthentication?

AndroidARTabout/Runtime

AndroidBackupServiceabout/Anoverview

AndroidDebugBridge(adb)/CheckingpoliciesusingadbAndroidIntentsystem

about/TheAndroidIntentsystemwebsiteassociation,creating/Creatingawebsiteassociationapplinkverification,triggering/Triggeringapplinkverificationapplinksettingsandmanagement/Applinksettingsandmanagement

AndroidInterfaceDefinitionLanguage(AIDL)URL/ConnectingtotheChromeservice

AndroidKeystorechangesabout/AndroidKeystorechanges

AndroidKeystoreSystemURL/Credentials’GracePeriod

AndroidMarshmallowaudiofeatures/Audiofeaturesvideofeatures/Videofeaturescamerafeatures/Camerafeaturesbehavioralchanges/Behavioralchanges

AndroidMarshmallowchangesbehavioralchanges/Behavioralchangessingle-usedeviceimprovements/Single-usedeviceimprovementsapps,silentlyinstalling/Silentlyinstalling/uninstallingappsapps,silentlyuninstalling/Silentlyinstalling/uninstallingappsimprovedcertificateaccess,granting/Improvedcertificateaccessautomaticsystemupdates/Automaticsystemupdatesthird-partycertificateinstallation/Third-partycertificateinstallationdatausagestatistics,querying/Datausagestatisticsruntimepermissions,managing/ManagingruntimepermissionsVPN,accessing/VPNaccessanddisplay

VPN,configuring/VPNaccessanddisplayworkprofilestatus/Workprofilestatus

AndroidMarshmallowpermissionsabout/UnderstandingAndroidMarshmallowpermissionsdeclaringpermissions/Anoverviewpermissiongroups/Anoverview,PermissiongroupsPROTECTION_NORMALpermissions/AnoverviewINTERNETpermission/Anoverviewappsignaturepermissionsgranted/Anoverviewpermissionsgrantedbyusersatruntime/Anoverviewpermissions,revoking/Anoverviewruntimepermissions/Runtimepermissionsbestpractices/Bestpracticesandusagenotes,Honestycanbeagreatpolicymanaging/Needsupporthandlingruntimepermissions?

Androidpermissionsabout/AnoverviewofAndroidpermissions,Permissionspermissiongroupdefinitions/Permissiongroupdefinitionspermissions,impliedbyfeaturerequirements/Permissionsthatimplyfeaturerequirementsviewing,foreachapp/Viewingthepermissionsforeachapp

AndroidSDKToolsRevision24.3/SettingupfortestingAndroidSupportLibrary

about/NotificationsAndroidsystemflagspermissions

about/SomepermissionsarenormalandsafertouseApacheHTTPclientremoval

about/ApacheHTTPclientremovalAPKvalidation

about/APKvalidationApple’sWebkit/WhatisWebView?ApplicationInfofields

about/Removablestorageadoptionapplinks

testing/Testingapplinksmanifest,checking/Checkingmanifestandlistingdomainsdomains,listing/CheckingmanifestandlistingdomainsDigitalAssetLinksAPI/TheDigitalAssetLinksAPIintent,testing/Testingourintentpolicies,checkingwithadb/Checkingpoliciesusingadb

appsinstalling,silently/Silentlyinstalling/uninstallingappsuninstalling,silently/Silentlyinstalling/uninstallingapps

AppStandbymodeabout/TheAppStandbymode

device,inAppStandbymode/WhathappenstoappswhenintheAppStandbymode?apps,testingwith/TestingappswiththeAppStandbymodeexcludedappsandsettings/Excludedappsandsettingspointsandtips/Tips

assistant/TheAssistAPIAssistAPI/TheAssistAPIaudiofeatures,AndroidMarshmallow

about/AudiofeaturessupportforMIDIprotocol/SupportfortheMIDIprotocolMidiManager/MidiManagerdigitalaudiocaptureandplayback/Digitalaudiocaptureandplaybackaudioandinputdevices/Audioandinputdevicesinformationonaudiodevices/Informationonaudiodeviceschanges,inAudioManager/ChangesinAudioManager

authenticate()method/Howdoweusefingerprintauthentication?automaticbackup

about/Anoverviewsubtopics/Importantbytesexcludeddata/WhattoexcludefromthebackupBackupAgent/BackupAgentandbackupeventsbackupevents/BackupAgentandbackupevents

automaticsystemupdates/Automaticsystemupdates

Bbackupconfigurationsyntax

<include>tag/Thebackupconfigurationsyntax<exclude>tag/Thebackupconfigurationsyntaxdomain/Thebackupconfigurationsyntax

backupconfigurationtestingabout/Backupconfigurationtestingbackuplogs,setting/Settingbackuplogsbackupphase,testing/Testingthebackupphaserestorephase,testing/Testingtherestorephasetroubleshooting/Troubleshooting

BackupManagerserviceabout/Anoverview

behavioralchanges,AndroidMarshmallowworkcontacts,displayoption/TheworkprofilecontactsdisplayoptionWi-Ficonfigurationoptions/Wi-FiconfigurationoptionsWi-Ficonfigurationlock/TheWi-FiconfigurationlockWorkPolicyController,adding/WorkPolicyControlleradditionDevicePolicyManagerchanges/DevicePolicyManagerchanges

BluetoothAPIabout/BluetoothAPIChangesstylussupport/Bluetoothstylussupport

Ccamerafeatures

about/CamerafeaturesflashlightAPI/TheflashlightAPIreprocessingAPI/ThereprocessingAPIchanges,incameraservice/Changesinthecameraservice

Chromecustomtababout/WhatisaChromecustomtab?WebView/WhatisWebView?customizationoptions/Customizationoptionsusing/WhentouseChromecustomtabs,CanweuseChromecustomtabs?implementationguide/TheimplementationguidecustomUI/CustomUIandtabinteractiontabinteraction/CustomUIandtabinteractioncustomactionbutton/Thecustomactionbuttoncustommenu,configuring/Configuringacustommenucustomenteranimations,configuring/Configuringcustomenterandexitanimationscustomexitanimations,configuring/Configuringcustomenterandexitanimationswarmingup/Chromewarm-upChromeservice,connecting/ConnectingtotheChromeservicebrowserprocess,warmingup/Warmingupthebrowserprocessnewtabsession,creating/CreatinganewtabsessionprefetchingURL,setting/SettingtheprefetchingURLconnectioncallback/Customtabsconnectioncallback

Chromiumproject/WhatisWebView?ChubbyTabb

URL/CustomUIandtabinteractioncleartextnetworktraffic

about/Cleartextnetworktrafficdownside/So,whatdowedowiththecleartextnetworktrafficflag?using/So,whatdowedowiththecleartextnetworktrafficflag?

codingpermissionsabout/Takingcodingpermissionsintoaccounttesting/Testingpermissionscoding,forruntimepermissions/Codingforruntimepermissions

Contextmethodsabout/Removablestorageadoption

Credentials’GracePeriodusing/Credentials’GracePeriod

CredGraceActivity/Credentials’GracePeriodcustomizationoptions,Chromecustomtab/Customizationoptions

CustomTabsHelperURL/CanweuseChromecustomtabs?

customURIscheme/TheAndroidIntentsystem

DDalvik

about/Runtimedatabackupconfiguration

about/Databackupconfigurationdata,includingorexcluding/Includingorexcludingdatabackupconfigurationsyntax/Thebackupconfigurationsyntaxpptingout,fromappdatabackup/Optingoutfromappdatabackup

datausagestatisticsquerying/Datausagestatistics

DevicePolicyManagerURL/DevicePolicyManagerchanges

DevicePolicyManager,changessetCameraDisabled()/DevicePolicyManagerchangessetKeyguardDisabledFeatures()/DevicePolicyManagerchangeskeyguardrestrictions,setting/DevicePolicyManagerchangescreateAndInitializeUser()/DevicePolicyManagerchangescreateUser()/DevicePolicyManagerchangessetScreenCaptureDisabled()method/DevicePolicyManagerchangesEXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUM/DevicePolicyManagerchangesEXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM/DevicePolicyManagerchangesEXTRA_PROVISIONING_RESET_PROTECTION_PARAMETERS/DevicePolicyManagerchangesEXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE,using/DevicePolicyManagerchangesRESULT_CANCELED/DevicePolicyManagerchangessetofsettings,disabling/DevicePolicyManagerchangesWIFI_DEVICE_OWNER_CONFIGS_LOCKDOWNsetting,enabling/DevicePolicyManagerchanges

DigitalAssetLinksAPI/TheDigitalAssetLinksAPIdigitalaudiocaptureandplayback/DigitalaudiocaptureandplaybackDigitalSignatureAlgorithm(DSA)

about/AndroidKeystorechangesDirectShare

about/DirectSharebestpractices/DirectSharebestpractices

Dozemodeabout/TheDozemodedevice,indozingstate/Whathappenstoappswhenadeviceisdozing?apps,testingwith/TestingappswithDozemode

Eemulator

settingup,URL/Settingupfortesting

FFingerprintauthenticationAPI

about/TheFingerprintauthenticationAPIadding/TheFingerprintauthenticationAPIusing/Howdoweusefingerprintauthentication?settingup,fortesting/Settingupfortesting

GGoogleCloudMessaging(GCM)

about/DatabackupconfigurationGoogleI/O2015/TheAssistAPIGoogleNow/VoiceinteractionsGooglePlayforWork/Silentlyinstalling/uninstallingappsGroupID

about/AnoverviewofAndroidpermissions

Hhardwareidentifier

about/Hardwareidentifier

IimprovedBluetoothlowenergyscanning

about/ImprovedBluetoothlowenergyscanningimprovedcertificateaccess

granting/Improvedcertificateaccessintentfilters/TheAndroidIntentsystemisKeyguardSecure()method/Credentials’GracePeriod

JJSONfile

about/Whythisfile?

Kkiosks/Silentlyinstalling/uninstallingapps

Llaunchhandler/TheAndroidIntentsystemLinuxuserID

about/AnoverviewofAndroidpermissions

MMidiManager/MidiManagerMIDIprotocol/SupportfortheMIDIprotocol

Nnotificationsfeature

about/Notifications

Ppendingintent

URL/CustomUIandtabinteractionpermissionfailure

about/AnoverviewofAndroidpermissionspower-savingmodes

about/Power-savingmodesDozemode/TheDozemodeAppStandbymode/TheAppStandbymode

Rremovablestorageadoption

about/RemovablestorageadoptionreprocessingAPI/ThereprocessingAPI

android.media.ImageWriter/android.media.ImageWriterandroid.media.ImageReader/android.media.ImageReader

runtimeabout/Runtime

runtimepermissionsmanaging/Managingruntimepermissions

SSecureSocketLayer(SSL)/So,whatdowedowiththecleartextnetworktrafficflag?sendBroadcast(Intent)method

about/AnoverviewofAndroidpermissionssetUserAuthenticationValidityDurationSeconds()method/Credentials’GracePeriodSharedPreferences/BackupAgentandbackupeventssingle-usedeviceimprovements

setKeyguardDisabled(),using/Single-usedeviceimprovementssetStatusBarDisabled(),using/Single-usedeviceimprovementsUserManager.DISALLOW_SAFE_BOOT,using/Single-usedeviceimprovementsSTAY_ON_WHILE_PLUGGED_IN,using/Single-usedeviceimprovements

stylusabout/Bluetoothstylussupport

SystemUpdatePolicyTYPE_INSTALL_AUTOMATICoption/AutomaticsystemupdatesTYPE_INSTALL_WINDOWEDoption/AutomaticsystemupdatesTYPE_POSTPONEoption/Automaticsystemupdates

Ttextselection

about/Textselectionsupportlibrarynotice/Supportlibrarynotice

Third-partycertificateinstallationDevicePolicyManagerAPIs,calling/Third-partycertificateinstallation

Torchi/TheflashlightAPI

UURI(UniformResourceIdentifier)/TheAndroidIntentsystemUSBconnection

about/USBconnection

Vvideofeatures

about/Videofeaturesandroid.media.MediaSync/android.media.MediaSyncMediaCodecInfo.CodecCapabilities.getMaxSupportedInstances/MediaCodecInfo.CodecCapabilities.getMaxSupportedInstancesMediaPlayer.setPlaybackParams/MediaPlayer.setPlaybackParams

voiceactions/Voiceinteractionsvoiceinteractions/VoiceinteractionsVPN

profileowner/VPNaccessanddisplaydeviceowner/VPNaccessanddisplay

WWebView

about/WhatisWebView?Wi-FiandnetworkingAPIs

about/Wi-FiandnetworkingchangesWorkPolicyController

about/WorkPolicyControlleradditionURL/WorkPolicyControlleraddition

workprofilestatuschecking/Workprofilestatus

YYUV/ThereprocessingAPI

Android 6 Essentials

Documents

Transcript of Android 6 Essentials