Cara cara Membuat Android

7/26/2019 Cara cara Membuat Android

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Anroid Application Development (Series II) 3-5hb November 2014

ASMATT ([email protected]) 1

Android Application

Development

Series II

Review


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Create Android Project

Project File >> New >> Project >> Android App

Project

Enter Application Name, Project Name & Package

Name;


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Android App Development Steps

Creating Your Emulator

Create your emulator

Eclipse: Window =>

Android Virtual Device

Manager, Choose New


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Before Execute Your App1) Select target API

(Choose Android API 19)

2) Select Device or Screensize (choose 5.1).

5) Click ok. Accept otherdefaults. Click this button to

create the emulator.

3) Give a name for thistarget. No space allowed.

4) Choose No skin

Run your app

Emulator will take some

time to be loaded

1) Expand your

project (src)

2) Click

here

3) Click run

button

4) Choose

this


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ANDROID CODING

Button & onClick Handler

Open activity_main.xml (your layout)


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Add an EditText, a Button & a TextView

Run your app


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Add onClick handler

Open main.xml

Add a new line (as in Line 21):17.

You can give

any name

Add handleClick method

Open myFirstButtonHandlerActivity.java

Add method handleClick()

Between the

last (two) }

A new method (beside

onCreate) to handle

onClick event


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myFirstButtonHandlerActivity.java1. packagecom.Suki.ButtonHandler;

2. importandroid.app.Activity;

3. importandroid.os.Bundle;

4. importandroid.view.View;

5. importandroid.widget.EditText;

6. importandroid.widget.TextView;

7. publicclassMyFirstButtonHandlerActivity extendsActivity {

8. /** Called when the activity is first created. */

9. @Override

10. publicvoidonCreate(Bundle savedInstanceState) {

11. super.onCreate(savedInstanceState);

12. setContentView(R.layout.main);

13. }

14.

15. publicvoidhandleClick(View v) {

16. // get a reference to editText1 from main.xml

17. EditText widget_editText1= (EditText) findViewById(R.id.editText1);

18. // get the text (input)

19. String inputText= widget_editText1.getText().toString();

20. // get a reference to textView1 from main.xml

21. TextView widget_textView1= (TextView) findViewById(R.id.textView1);

22. // put a message (from input) to the widget

23. widget_textView1.setText("Your Name: "+ inputText);

24. }25. }

Should be similar

with your onClick

button in the

activity_main.xml

Manipulate Numbers(Create a new project HandleNumber)


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Button onClick Handler for

HandleNumberActivity.java

1. publicvoidhandleNom(View v) {

2. EditText inputTeks= (EditText) findViewById(R.id.editText1);

3. String teks= inputTeks.getText().toString();

4. floatcelsius = Float.parseFloat(teks);

5. floatfaren = ((celsius * 9) / 5) + 32;

6.

7. TextView label1= (TextView) findViewById(R.id.textView1);

8. label1.setText(celsius+ " Celsius is equal to "+

9. faren+ " Farenheit.");

10. }

We want to produce/output something like this,

38.0Celsius is equal to 100.4 Farenheit.

Exercise:

Power 3 Calculator


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Try This:

Multiplication Calculator

Exercise: Multiplication Calculator

1. publicvoidCalc(View v) {

2. EditText et1= (EditText)findViewById(R.id.editText1);

3. String nomStr1= et1.getText().toString();

4. intnomInt1= Integer.parseInt(nomStr1);

5. EditText et2= (EditText)findViewById(R.id.editText2);

6. String nomStr2= et2.getText().toString();

7. intnomInt2= Integer.parseInt(nomStr2);

8. inthasil= nomInt1*nomInt2;

9. TextView tv= (TextView)findViewById(R.id.textView2);

10. tv.setText("Result is: "+ hasil);

11.}


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Exercise:

Basic Calculator

DUPLICATING & IMPORTING

AN ANDROID PROJECT


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Duplicate an Android Project

Simply Copy &

Paste (in Eclipse)

Highlight the

project

Ctrl-C (Copy)

Ctrl-V (Paste)

Enter a newproject name

Copy a project from Another Source

Eclipse: File -> Import

Choose Android ->

Existing AndroidCode Into Workspace

Next -> Browse ->locate the project

OK -> tick Copyproject intoworkspace-> Finish


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Using Basic Selection

26

The if Statement Syntax

The ifstatement has the following syntax:

if ( condition) {

statement(s);}

ifis a Java

reserved word

The conditionmust be a

boolean expression. It must

evaluate to either true or false.

If the conditionis true the statement(s)is executed.

If it is false the statement(s) is skipped.


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27

Relational Operators

A condition often uses one of Java's equality operators or

relational operators, which all return boolean results:

== equal to

!= not equal to

greater than

= greater than or equal to

Try This: Odd or Even Number


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Try This: Odd or Even Number

1. EditText et = (EditText) findViewById(R.id.editText1);

2. String nomStr = et.getText().toString();

3. intnom = Integer.parseInt(nomStr);

4. String hasil = "Not known yet";

5. if(nom%2 == 0) { //or (nom/2*2 == nom)

6. hasil = "EVEN";

7. } else{

8. hasil = "ODD";

9. }

10. TextView tv = (TextView) findViewById(R.id.textView2);

11. tv.setText("The number is "+ hasil);

Exercise: Pass or Fail?

Request a mark value from user

Determine either the mark is pass or fail.

50 & above is considered pass.


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Tips: Background Color & Images

Http://html-color-codes.info

VIDEO

Local & Remote


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VIDEO

Supported File: 3gp, mp4, ts.

Supported network protocols:

HTTP/HTTPS progressive streaming.

Ex:http://fr3.ah.fm:9000

HTTP/HTTPS live streaming (HLS).

Ex: http://www.playon.tv/online/iphone5/main.m3u8

Real Time Streaming Protocol (RTSP).

Ex:rtsp://208.77.20.52:1935/dmm1/ten RTMP Protocol is not supported

Ex:rtmp://109.201.157.183/ren/ren3
http://fr3.ah.fm:9000/http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://www.playon.tv/online/iphone5/main.m3u8http://fr3.ah.fm:9000/http://fr3.ah.fm:9000/http://fr3.ah.fm:9000/http://fr3.ah.fm:9000/http://fr3.ah.fm:9000/http://fr3.ah.fm:9000/


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Remote Video

1. protectedvoidonCreate(Bundle savedInstanceState) {


3. setContentView(R.layout.activity_main);

4.

5. String url = "http://download.wavetlan.com/SVV/Media/HTTP/H264/ Talkinghead_Media/H264_test2_Talkinghead_mp4_480x320.mp4";

6. Uri uri = Uri.parse(url);

7. VideoView video = (VideoView) findViewById(R.id.videoView1);

8.

9. final MediaController ctlr = newMediaController(this);

10. video.setMediaController(ctlr);

11. video.setVideoURI(uri);

12. video.requestFocus();

13. video.setOnPreparedListener(newOnPreparedListener() {

14. ProgressBar pb=(ProgressBar) findViewById(R.id.progressBar1);

15.

16. publicvoidonPrepared(MediaPlayer mp) {17. pb. setVisibility(View.GONE);// Close the progress bar and play the video

18. ctlr.setAnchorView(video);

19. video.start();

20. }

21. });

22. }

Remote Video




4.

5. String url = " https://www.dropbox.com/s/xj3y0ofg7a3dqln/frozen_playice.mp4";



8.







15.

16. publicvoidonPrepared(MediaPlayer mp) {

17. pb. setVisibility(View.GONE);// Close the progress bar and play the video


19. video.start();

20. }

21. });

22. }


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Live TV




4.

5. String url = "http://dl.dropboxusercontent.com/u/59242226/play/smarttv/channel/tvtiga.m3u8" ;



8.







15.

16. publicvoidonPrepared(MediaPlayer mp) {17. pb. setVisibility(View.GONE);// Close the progress bar and play the video


19. video.start();

20. }

21. });

22. }

Local Video




4. Uri uri = Uri.parse("android.resource://"+

getApplication().getPackageName()+"/"+R.raw.frozen_playice);

5. VideoView video = (VideoView)findViewById(R.id.videoView1);

6. MediaController ctlr = newMediaController(this);



9. video.start();

10. }


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PLAY AN AUDIO

1. public class MainActivity extends Activity {

2. private MediaPlayer mp;

3. @Override

4. public void onCreate(Bundle savedInstanceState) {



7. mp = new MediaPlayer();

8. }

9.

10. public void playSound(View v){11. mp = MediaPlayer.create(MainActivity.this,

R.raw.lagu);

12. mp.start();

13. }

14.}

Media Player source.

TALKING ANDROID

Android is Interesting!


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Try This: Text-to-Speech

1. publicclassMainActivity extendsActivityimplementsOnInitListener {

2. TextToSpeech talker;

3.

4. @Override

5. protectedvoidonCreate(BundlesavedInstanceState) {


7. setContentView(R.layout.activity_main);8. talker = new TextToSpeech(this, this);

9. }

Try This: Text-to-Speech

10. @Override

11. publicvoidonInit(intarg0) {

12. // TODOAuto-generated method stub

13. talker.setLanguage(Locale.UK);

14. talker.setSpeechRate((float)kadar);

15. talker.speak(teks,TextToSpeech.QUEUE_FLUSH, null);

16.

17. }


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TOUCH HANDLING

Try This: Android Life-Cycle App

We can implement/overrides all built-in

methods using the Eclipse.

Eclipse: Source -> Override/Implement

methods

Tick all related methods


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Allows us to send brief messages to our end users.

Toast.makeText(this, Our Text", Toast.LENGTH_SHORT).show();

Three parameters:

The activity that is running this Toast alert

What the message should be

How long to show the Toast pop-up

import android.widget.Toast;

Introducing TOAST WIDGET

Try This: Touch, Move & Lift Event


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Try This: Touch Event

1. @Override

2. publicbooleanonTouchEvent(MotionEvent event) {

3. intdetectTouch = event.getAction();

4. if(detectTouch==MotionEvent.ACTION_DOWN) {

5. Toast.makeText(getApplicationContext(),

"...is moving", Toast.LENGTH_SHORT).show();

6. }

7. returntrue;

8. }

Try This: Detecting Swipe Event

1. publicclassGestureActivity extendsActivity {

2. floatx1, x2;

3. floaty1, y2;

4. @Override

5. protectedvoidonCreate(BundlesavedInstanceState) {


7. setContentView(R.layout.gesture);

8. }


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9. @Override


11. intaction = event.getAction();

12. switch(action) {

13. caseMotionEvent.ACTION_DOWN:

14. x1= event.getX();

15. y1= event.getY();

16. break;

17. caseMotionEvent.ACTION_UP:

18. x2= event.getX();

19. y2= event.getY();


20. // if left to right sweep event on screen

21. if(x1< x2) { //or better (x2-x1>50)

22. Toast.makeText(this, "Left to Right Swap Performed",Toast.LENGTH_LONG).show();

23. }

24. // if right to left sweep event on screen

25. if(x1> x2) { //or (x1-x2> 50)

26. Toast.makeText(this, "Right to Left Swap Performed",Toast.LENGTH_LONG).show();

27. }

28. // if UP to Down sweep event on screen

29. if(y1< y2) {

30. Toast.makeText(this, "UP to Down Swap Performed",Toast.LENGTH_LONG).show();

31. }


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32. // if Down to UP sweep event on screen

33. if(y1> y2) {

34. Toast.makeText(this,"Down to UP Swap Performed",Toast.LENGTH_LONG).show();

35. }

36. break; // for MOVE_UP event

37. }

38. returntrue;

39.}

Exercise

When a user performs this swipe, play a

song.

When a user performs this swipe, stop thesong.


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OPEN ANOTHER LAYOUT

Open Another Layout

The easier way to move from one layout to

another layout is to use setContentView().


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Try This: Open Another Layout

Try This: Open Another Layout

1. publicclassMainActivity extendsActivity {

2. @Override

3. protectedvoidonCreate(Bundle savedInstanceState) {4. super.onCreate(savedInstanceState);


6. }

7. publicvoidOpen_Layout2(View v) {

8. setContentView(R.layout.second_layout);

9. }

10.}


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Exercise: Open Another Layout

Try implements BACK

button (to return to the

main page).


Sample Solution

1. publicvoidOpen_Layout2(View v) {


3. }

4. publicvoidHandleBACK(View v) {


6. }


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Sample Solution (for touch screen)

1. @Override



4. intdetectTouch = event.getAction();

5. if(detectTouch==MotionEvent.ACTION_DOWN) {


7. }

8. returntrue;

9. }


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ACTION BAR MENU

Try This: Create an Action Bar Menu


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2 easy steps:

List of menu options can be prepared by

modifying main.xml (res -> menu).

Override the public boolean

onOptionsItemSelected(MenuItem item) {}

Start the project by choosing theme Holo

Light with Dark Action Bar



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menu.xml: (copy & modify tag)

1.

5.

10.


15. 21.

27.

33.


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.java: (copy & modify if statement in method onOptionsItemSelected)

1. @Override

2. publicbooleanonOptionsItemSelected(MenuItem item) {

3. // Handle action bar item clicks here. The action barwill

4. // automatically handle clicks on the Home/Up button,so long

5. // as you specify a parent activity inAndroidManifest.xml.

6. intid = item.getItemId();7. if(id == R.id.main_acreen) {


9. }

10. if(id == R.id.layout2) {

11. setContentView(R.layout.activity_main2);

12. }


.java: (copy & modify if statement in method onOptionsItemSelected)

13. if(id == R.id.play_music) {

14. mp= MediaPlayer.create(getApplicationContext(),R.raw.uum_song);

15. mp.start();

16. }

17. if(id == R.id.stop_music) {

18. mp.stop();

19. }

20. if(id == R.id.bantuan) {

21. setContentView(R.layout.screen_bantuan);

22. }

23. returnsuper.onOptionsItemSelected(item);

24.}


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DUPLICATING & IMPORTINGAN ANDROID PROJECT

Duplicate an Android Project

Simply Copy &

Paste (in Eclipse)

Highlight the

project

Ctrl-C (Copy)

Ctrl-V (Paste)

Enter a new

project name


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Copy a project from Another Source

Eclipse: File -> Import

Choose Android ->Existing AndroidCode Into Workspace

Next -> Browse ->locate the project

OK -> tick Copyproject intoworkspace-> Finish

Download Internet Resource


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Try This:

Download am Image

Start with Android 2.3.3


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The layout

The coding

1. publicvoidHandleDownload(View v) {

2. String url = "http://crackberry.com/sites/crackberry.com/" +

3. "files/styles/large/public/topic_images/2013/ANDROID.png" ;

4. try{

5. Toast.makeText(getApplicationContext(), "downloading...",

Toast.LENGTH_LONG).show();

6. Bitmap imgResult = BitmapFactory.decodeStream((InputStream)

7. newURL(url).getContent());

8. ImageView imgView = (ImageView) findViewById(R.id.imageView1);

9. imgView.setImageBitmap(imgResult);

10. Toast.makeText(getApplicationContext(), "is Displaying...",


11. } catch(Exception e) {}

12. }

*** Dont forget to set the Internet permission


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The Result

Now run it on

Emulator API19


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Try this: Download in

the Android Thread

Try this: Download in the Android Thread

1. publicclassMainActivity extendsActionBarActivity {

2. finalString url="http://crackberry.com/sites/crackberry.com/" +"files/styles/large/public/topic_images/2013/ANDROID.png";

3. @Override4. protectedvoidonCreate(Bundle savedInstanceState) {



7. }


9. newmyDownloadThread().execute();10. Toast.makeText(getApplicationContext(), "is downloading...",


11. }


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12.privateclassmyDownloadThread extendsAsyncTask {

13. @Override

14. protectedBitmap doInBackground(Void... arg0) {

15. Bitmap imgResult = null;

16. try{

17. imgResult =BitmapFactory.decodeStream((InputStream) new

URL(url).getContent());

18. } catch(Exception e) {}19. returnimgResult;

20. }


21. protectedvoidonPostExecute(Bitmapresult) {


"is displaying...",Toast.LENGTH_SHORT).show();

23. ImageView imgView = (ImageView)findViewById(R.id.imageView1);

24. imgView.setImageBitmap(result);

25. }

26. }

27.}


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(2014)

Thread/AsynTask

Why use thread in Android?

When an Android application is first started, the runtime system

creates a single thread in which all application components will run

This thread is referred to as the main thread(also known as UI thread,

since it modifies the user interface and handles input events)

All code of an Android application (incl. additional components) runs in the

main thread and every statement is executed after each other

If you perform a long lasting operation(e.g accessing data from the Internet)

the application is blocked until the corresponding operation has finished.


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Why use thread in Android?

Android enforces a worst case reaction time of applications.

If an activity does not react within 5 seconds to user input,

the Android system displays an Application not responding (ANR) dialog.

From this dialog the user can choose to stop the application

NOTE!

LOGO

Android AsynTask

Enables proper and easy use of the UI thread. This

class allows to perform background operations and

publish results on the UI thread without having to

manipulate threads and/or handlers.


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Introduction

AsyncTask is a generic class, it uses 3 types:

AsyncTask.

Paramsthe input. What you pass to the

AsyncTask

Progressif you have any updates, passed to

onProgressUpdate()

Resultthe output. What returns doInBackground()

Example:private class MyTask extends AsyncTask { }

OR

private class MyTask2 extends AsyncTask { }

Introduction

The most common methods you will need to

implement (overrides) are these:

1. onPreExecute()called on the UI thread

before the thread starts running.2. doInBackground(Params)put all the code

you want the application to perform in

background.

3. onProgressUpdate() - called when you invoke

publishProgress() in the doInBackground().

4. onPostExecute(Result)called after the

background thread finishes.


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Example

Hello World! Become

Downloading

Then progressing

values will appear

Final msg, All Done!

Example

1. publicclassMainActivity extendsActivity {

2. TextView tv;

3. @Override

4. publicvoidonCreate(Bundle savedInstanceState) {

5. Super.onCreate(savedInstanceState);


7. tv= (TextView) findViewById(R.id.textView1);

8. }

9. publicvoidhandleAsynTask(View v) {

10. // Starting the task. Pass an url as the parameter.

11. newMyTask().execute("http://ahmadsuki.blogspot.com");

12. }

AsynTask

class

1stparam input for

AsynTask class. Leave it

blank if first param Void


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Example

13. privateclassMyTask extendsAsyncTask {14. @Override

15. protectedvoidonPreExecute() {

16. super.onPreExecute();

17. tv.setText("Downloading...");

18. }

19. @Override

20. protectedString doInBackground(String... params) {

21. String url = params[0];

22. // Dummy code

23. for(inti = 0; i


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Summary


2. newMyTask().execute("http://ahmadsuki.blogspot.com");

3. }

4. privateclassMyTask extendsAsyncTask {


6. }

7. protectedString doInBackground(String... params) {

8. publishProgress(i);

9. return"All Done!";

10. }

11. protectedvoidonProgressUpdate(Integer... values) {

12. }

13. protectedvoidonPostExecute(String result) {

14. }

15. }

Summary


2. newMyTask().execute();

3. }

4. privateclassMyTask extendsAsyncTask {


6. }

7. protectedVoid doInBackground(Void... voids) {

8. publishProgress(i);

9. returnnull;

10. }

11. protectedvoidonProgressUpdate(Integer... values) {

12. }

13. //protectedvoidonPostExecute(String result) {

14. //} NOT IMPLEMENTED

15. }


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Return to Downloading Case:

Observe the Structure1. public class MainActivity extends ActionBarActivity {

2. final String url = "http://crackberry.com/sites/crackberry.com/"

3.

4. @Override

5. protected void onCreate(Bundle savedInstanceState) {

6. }

7. public void HandleDownload(View v) {

8. new myDownloadThread().execute();

9. }

10. private class myDownloadThread extends AsyncTask {

11. @Override12. protected BitmapdoInBackground(Void... arg0) {

13. return imgResult;

14. }

15. protected void onPostExecute(Bitmapresult) {

16. }

17. }

1

2

3


Analysis Issues1. public class MainActivity extends ActionBarActivity {


3.

4. @Override


6. }



9. }


11. @Override

12. protected BitmapdoInBackground(Void... arg0) {


14. }

15. protected void onPostExecute(Bitmapresult) {

16. }

17. }

Can we display the result here (instead of on onPostExecute?

Toast.makeText(getApplicationContext(), "is displaying...",

Toast.LENGTH_SHORT).show();

ImageView imgView = (ImageView)

findViewById(R.id. imageView1);

imgView.setImageBitmap(result);


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Analysis Issues1. public class MainActivity extends ActionBarActivity {


3.

4. @Override


6. }



9. Toast.makeText(getApplicationContext(), "is downloading...",

10. Toast.LENGTH_LONG).show();

11. }


13. @Override

14. protected BitmapdoInBackground(Void... arg0) {


16. }

17. }

Can we code this toast message in the AsyncTask

class?

Toast.makeText(getApplicationContext(), "is

downloading...",



Analysis Issues (Try This)

Put the cursor inside

AsyncTask class, choose

menu source, then select

Override/Implement

Methods


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Analysis Issues (passing data through 1stparam)


2. String url = http://crackberry.com/sites/crackberry.com/+"files/styles/large/public/topic_images/2013/ANDROID.png";

3. newmyDownloadThread().execute(url);4. }

5. privateclassmyDownloadThread extendsAsyncTask {

6. @Override

7. protectedBitmap doInBackground(String... arg0) {8. Bitmap imgResult = null;

9. try{

10. imgResult = BitmapFactory.decodeStream((InputStream) new

URL(arg0[0]).getContent());


Analysis Issues (passing data through 1stparam)

1. privateclassmyDownloadThread extendsAsyncTask {

2. @Override

3. protectedBitmap doInBackground(String... arg0) {

4. try{

5. int sizeFile= new URL(arg0[0]).openConnection().getContentLength();

6. publishProgress(sizeFile);

7. imgResult = BitmapFactory.decodeStream((InputStream) new

URL(arg0[0]).getContent());


9. @Override

10. protected void onProgressUpdate(Integer... values) {

11. super.onProgressUpdate(values);

12. Toast.makeText(getApplicationContext(), "The file size is =

"+values[0], Toast.LENGTH_LONG).show();

13. }
http://crackberry.com/sites/crackberry.com/http://crackberry.com/sites/crackberry.com/http://crackberry.com/sites/crackberry.com/http://crackberry.com/sites/crackberry.com/


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(2014)

EXTRA: DOWNLOAD IMAGE FROMTHE INTERNET

Internet Access Permission

Before your application can access the Internet, it needs

to be

granted permission for Internet access..

Add this in the AndroidManifest.xml:


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Background Thread

Starting with Android 3.0 (Honeycomb) you may not

perform

network operations on your main UI thread

This will cause a NetworkOnMainThreadException

In order to solve this, you need to use background

thread:Handler

or

AsyncTask

Downloading Image: Example

Try to do this application:

(Use AsyncTask for the downloading task)


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Downloading the image must be performed as

a background task (NEVER in the main UI

thread)

Therefore, in this example, we will use

AsyncTask for the downloading job.


Use this link: https://www.dropbox.com/s/0ghcyv2lmsi0t2j/myBee.bmp

1. Create the main layout (xml) for your

Activity. It should have:

A TextView for the titleA ProgressBar (initially invisible) to show

progress

A TextView to display % progress

An ImageView to display the downloaded

image

(set background color to black)

An EditText to enter the image URL

A Button to start the downloading



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2. In your Activity class,

get handles to the all of the views used (call findViewById( ))

inside the onCreate() method

define the button onclick method. In this method:

Get the String from the url address TextView

Create the AsyncTask object & call its execute() method by

passing the url address(String) as its parameter

public void download(View v) {

String url = etUrl.getText().toString().trim();new ImageDownloader().execute(url);

}

*ImageDownloaderis the name of

our AsyncTask


3. Create a subclass of AsyncTask names ImageDownloader, as a

private inner class inside your Activity class

- Use the three generic types as specified:

private class ImageDownloader extends

AsyncTask {

}



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4. Override all the fourmethods in your AsyncTask , starting with the

onPreExecute() method.

- This is for initialising purpose

@Override

protected void onPreExecute() {

progress = 0; //declare this int variable as global in your AsyncTask

pb.setVisibility(View.VISIBLE);

Toast.makeText(LoadImageAsyncTaskActivity.this,

"starting download", Toast.LENGTH_SHORT).show();

super.onPreExecute();}

onPreExecute() method:


5. Override the doInBackground () method.

- This is for the background task done by the background thread

@Override

protected Bitmap doInBackground(String... urls) {

Bitmap bmp = loadImageFromNetwork(urls[0]); //do the loading task

while (progress < 100) {

progress += 1;

publishProgress(progress); //update progress to UI thread

SystemClock.sleep(100); //to slowdown the system

}

return bmp;

}

doInBackground() method:



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6. Override the onProgressUpdate () method.

- This is to show download progress in the ProgressBar and

TextView on main UI thread

@Override

protected void onProgressUpdate(Integer... values) {

pb.setProgress(values[0]);

percent.setText(values[0] + "%");

}

onProgressUpdate() method:


Downloading Image Example

7. Override the onPostExecute () method.

- This is to display the result (image) in the ImageView &

a message that download has completed (using Toast)

@Override

protected void onPostExecute(Bitmap result) {

img.setImageBitmap(result);

Toast.makeText(LoadImageAsyncTaskActivity.this,

"download complete", Toast.LENGTH_SHORT).show();

}

onPostExecute() method:


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8. Define the loadImageFromNetwork () method.

- This method do the actual work of loading the image from the

given url address

private Bitmap loadImageFromNetwork(String url) {try {

Bitmap bitmap = BitmapFactory

.decodeStream((InputStream) new URL(url).getContent());

// URL urlObj = new URL(url);

// InputStream in = (InputStream) urlObj.getContent();

//Bitmap bitmap = BitmapFactory.decodeStream(in);return bitmap;

} catch (Exception e) {

e.printStackTrace();

Log.d("getBmpFromUrl error: ", e.getMessage().toString());

return null;

}

}

loadImageFromNetwork() method:


9. Add permission for Internet access in your manifest file.


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(2014)

DOWNLOAD TEXT FILE FROM THEINTERNET

(2014)

Try This: Download a Text File


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(2014)


1. publicvoiddownloadTextFile(View v) {

2. InputStream inputStream = null;

3. String theString = "";

4. String url = "http://textfiles.com/100";

5. TextView tv = (TextView)

findViewById(R.id.textView1);

6. tv.setText("URL: "+ url);

(2014)


7. try{

8. //get the TextFile as an inputstream

9. inputStream = newDefaultHttpClient().execute(new

HttpGet(url)).getEntity().getContent();

10. // convert inputstream to BufferedReader

11. BufferedReader reader = newBufferedReader(new

InputStreamReader(inputStream));

12. //Read from bufferedReader to String

13. for(String line = reader.readLine(); line != null; line =

reader.readLine())

14. theString += line;

15. inputStream.close();



18. et.setText(theString);


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(2014)

(2014)


(alternative codingwithout thread yet)

1. publicclassMainActivity extendsActionBarActivity {

2. InputStream inputStream= null;

3. String theString= "";

4. finalString url= "http://textfiles.com/100";

5. @Override




9. }


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(2014)






13. String result = readFile(url);


15. et.setText(result);

16. }

(2014)



17.publicString readFile (String url){

18.try{

19. inputStream= newDefaultHttpClient().execute(new

HttpGet(url)).getEntity().getContent();

20. BufferedReader reader = newBufferedReader(newInputStreamReader(inputStream));

21. for(String line = reader.readLine(); line != null; line =

reader.readLine())

22. theString+= line;


24.} catch(Exception e) {

25.Log.d("InputStream", e.getLocalizedMessage());

26.}

27.returntheString;

28.}


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(2014)

Hide & UnHide the EditView

(2014)


1.


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(2014)





4. String result = readFile(url);


6. et.setVisibility(et.VISIBLE);

7. et.setText(result);

8. }

(2014)

Try This:

Download a Text File in AsyncTask


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(2014)

Try This:





4. newMyDownTF().execute();5. }

6. privateclassMyDownTF extendsAsyncTask{

7. @Override

8. protectedString doInBackground(Void... params) {

9. // TODOAuto-generated method stub10. String result = readFile(url);

11. returnresult;

12. }

(2014)

Try This:


13. @Override

14. protectedvoidonPostExecute(String strResult) {


16. super.onPostExecute(strResult);17. EditText et = (EditText) findViewById(R.id.editText1);

18. et.setVisibility(et.VISIBLE);

19. et.setText(strResult);

20. }


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(2014)

Try This: Download a Text File with

ProgressUpdate (line by line progress display)

(2014)





3. newMyDownTF().execute();

4. }



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6. @Override

7. protectedString doInBackground(Void... params) {8. String theString = "";

9. try{


11. inputStream= newDefaultHttpClient().execute(newHttpGet(url)).getEntity().getContent();

12. // convert inputstream to BufferedReader



15. for(String line = reader.readLine(); line != null; line = reader.readLine()) {

16. theString += line;

17. publishProgress(line);18. }19. inputStream.close();

20. } catch(Exception e) {

21. Log.d("InputStream", e.getLocalizedMessage());

22. }

23. returntheString;

24. }

(2014)



25.@Override

26.protectedvoidonProgressUpdate(String... values) {

27.// TODOAuto-generated method stub

28. super.onProgressUpdate(values);

29. tv.setText("Reading the file line by line:\n "+

values[0]);

30.}


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(2014)

Try This:

Download a WebPage File

(2014)

Try This:


Start by changing the

previous layout screen by

embedding a WebViewobject (remove the

EditText).


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(2014)

Try This:


1. @Override

2. protectedvoidonPostExecute(String

strResult) {


4. super.onPostExecute(strResult);

5. WebView wv = (WebView)

findViewById(R.id.webView1);

6. wv.loadData(strResult, "text/html", null);7. }

(2014)

Try This: Download a WebPage File

with a Dynamic URL


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(2014)


with a Dynamic URL


2. EditText ed = (EditText)findViewById(R.id.editText1);

3. String strURL =ed.getText().toString().trim();


5. tv.setText("URL: "+ strURL);

6. newMyDownTF().execute(strURL);

7. }


(2014)


with a Dynamic URL

9. @Override

10. protectedString doInBackground(String... params) {11. // TODOAuto-generated method stub

12. String theString = "";

13. String theURL = params[0];14. try{


16. inputStream= newDefaultHttpClient().execute(new

HttpGet(theURL)).getEntity().getContent();17. // convert inputstream to BufferedReader



20. for(String line = reader.readLine(); line != null; line = reader.readLine()) {

21. theString+= line;22. //publishProgress(line);

23. }


25. } catch(Exception e) {

26. Log.d("InputStream", e.getLocalizedMessage());

27. }

28. returntheString;29. }


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(2014)

Accessing Web Service

(2014)

Access Database Server:

Old ArchitectureCentralized System


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(2014)


Old ArchitectureClient/Server System

(2014)


Web ArchitectureWeb Server


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(2014)


Web ArchitectureWeb Service

(2014)


Web Service ArchitectureAndroid


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(2014)

JSON (JavaScript Object Notation)

very light weight

structured

easy to parse

human readable

the best alternative

to XML

(2014)

JSON (JavaScript Object

Notation)

square bracket ([) representsa JSON array

curly bracket ({) represents a

JSON object A JSON object contains a keythat is just a string. Pairs ofkey/value make up a JSONobject

Each key has a value thatcould be string , integer ordouble etc.


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(2014)

JSON Web Service Programming

3 main steps:

Download JSON file

Parsing

Display (formatting)

(2014)


Step 1: Download a JSON File

From our previous

download text file app,

just change it to the newJSON URL, e.g.

final String url =

"http://kis.kedah.gov.my/

majlis/majlis.json";


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(2014)

JSON Web Service Programming Exercise

Step 1: Download this JSON File

(2014)


Step 2: Parsing the JSON File


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(2014)



For parsing a JSON object, we have to create an object of class

JSONObject and specify a string containing JSON data to it. Its

syntax is:

JSONObject reader = new JSONObject(strJSON);

An JSON file consist of different object with different key/value

pair:

JSONObject sys = reader.getJSONObject("sys");

strCountry = sys.getString("country");

(2014)



1. publicvoidparsingJSON(String strJSON) {


3. JSONObject jsonObj;

4. String strDate, strTime;

5. try{

6. jsonObj = newJSONObject(strJSON);

7. strDate = jsonObj.getString("date");

8. strTime = jsonObj.getString("time");


"Your Date-Time: "+strDate+" - "+strTime,


10. } catch(JSONException e) {}

11.}


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(2014)


Step 3: Display the Output/Data

(2014)


Step 3: Display the Output/Data

1. JSONObject jsonObj;

2. String strDate="", strTime="";

3. try{


5. strDate = jsonObj.getString("date");

6. strTime = jsonObj.getString("time");

7. } catch(JSONException e) {}

8. TextView tvDate = (TextView)findViewById(R.id.textView3);

9. TextView tvTime =(TextView)findViewById(R.id.textView4);

10.tvDate.setText("Today Date: "+strDate);

11.tvTime.setText("US Time now: "+strTime);


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(2014)


Parsing the JSON File with Array Object []

(2014)


Parsing the JSON File with Array Object []

1. publicvoidparsingJSON(String strJSON) {


3. JSONObject jsonObj;4. String strMajlis="", strTarikh="",

strTempat="";

5. String strOutput = "Senarai Majlis

adalah seperti berikut:\n\n";

6. try{



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(2014)

Parsing the JSON File with

Array Object []

8. // Getting JSON Array node

9. JSONArray jsonArray =

jsonObj.getJSONArray

("majlis");

10. // looping through All array items

11. for(inti = 0; i 0) {

byte[] b = new byte[4096];

n = in.read(b);

if (n > 0)

out.append(new String(b, 0, n));

}return out.toString();

}

getResultFromEntity() method:

Example : A Simple Contact Rest-based Application


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8. Add permission for Internet access in your manifest file.


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Intro - II

One of the most common functionalities requiredin mobile applications is to call a web service toretrieve data.

This process involves requesting the web servicewith parameters, receiving the response andparsing it to obtain data.

Today the most common web services types areSOAPand REST.

Android does not provide a built in SOAP client,there are many third party libraries that can beused

Intro (REST)

REST (or RESTful) Services are an increasinglycommon paradigm for creating web servicesbecause of their simplicity and inherent platform

agnostic approach.

Many of the major service providers use REST,such as Twitter, Flickr, Facebook, etc.

REST allows for stateless, cacheable, and simpleto consume client-server architecture over HTTP.

Among the most popular formats are JSON(JavaScript Object Notation) and XML.


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Web Service with JSON

Simple JSON data:{

"data" : {

"id": "1234",

"category" : "my_category",

"name" : "my_name"

}

}

In order to parse the JSON data:

{

"data" : {

"id": "1234",

"category" : "my_category",

"name" : "my_name"

}

}

import org.json.JSONException;

import org.json.JSONObject;

Web Service with JSON - II1. String id;

2. String name;

3. String category;

4. String jsonString = "{\"data\" : {\"id\": "1234","category" :

Android","name" : Ahmad Suki"}}";

5. try{6. JSONObject jsonObj= new JSONObject(jsonString);

7. JSONObject dataObj = jsonObj.getJSONObject("data");

8. id = dataObj.getString("id");

9. category = dataObj.getString("category");

10. name = dataObj.getString("name");

11. }

12. catch(JSONException e) {

13. }


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Parsing JSON message

The results from List operation is in JSON format.

We have to parse the JSON formatted massage to extract the data inside ite.g. how to obtain only the names and phone numbers from the message


To parse JSON message, youll need these Java classes from

org.json package:

JSONObject

JSONArray

Also need the StringBuilder to append the string, representing

each of the JSON object, extracted from JSON message


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1. We need to do the parsing in the AsyncTask onPostExecute method:

(you can modify this method from the last example)

protected void onPostExecute(String result)

Notice that this method receives a string parameter, result, which contain

the JSON message that we are going to process. Also declare the

StringBuilder:

StringBuilder contactResult = new StringBuilder();

2. The JSON processing methods can throw exceptions, so add try and

catch blocks next:try {

}

catch (Exception e) {

et.setText(Something went wrong!");

e.printStackTrace();

}


3. Inside the try block, create a JSONObject, passing the JSON result

as the parameter:

JSONObject resultObject = new JSONObject(result) ;

4. We need to retrieve this contact array, using its name: Contacts. Get

the Contacts array from the JSON Object:

JSONArray contactArray= resultObject.getJSONArray("Contacts");


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5. After fetching the contact array, add a for loop to iterate through the

contacts:

for (int t=0; t


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9. Now move to after the catch block. If the processing has worked, we

display the result (convert the StringBuilder to String) in the EditText ,

otherwise we display an error message::

if(contactResult.length()>0)

et.setText(contactResult.toString());

else

et.setText("Sorry - no results!");

Cara cara Membuat Android

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