Eclipse Training - SWT & JFace

Eclipse Plug-ins and RCP

Training CourseStandard Widgets Toolkit

JFace

1October 2013Copyright © 2013 Luca D’Onofrio – RCP Solutions

1. SWT Overviewa) Understanding Layoutsb) Events and Listeners

Life-Cyclec) Containers and Widgets

Simple Widgets Complex Widgets

d) Class Hierarchye) Fonts, Colors, Imagesf) SWT Style Bits

Agenda


SWT is an open source widget toolkit for Java, designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.

It abstracts the OS rendering implementation.

SWT Overview


Layouts gives your windows a specific look, controlling the position and size of childrens and how childrens adapt to their parent

Understanding Layouts

4

Standard Layouts FillLayout lays out equal-

sized widgets in a single row or column

RowLayout lays out widgets in a row or rows, with fill, wrap, and spacing options

GridLayout lays out widgets in a grid

FormLayout lays out widgets by creating attachments for each of their sides

October 2013Copyright © 2013 Luca D’Onofrio – RCP Solutions

Events and Listeners (1/4)

5

TIP: much of the widget state is stored in the platform widget rather than in the widget itself (as for SWING)

class SWTWidgets Model

User

Widget

xxxEv ent

xxxListener

+ eventHandler()

«interface»xxxListener

Trigger the source

«flow»



6

sd Business Process Model

:User

:Widget :xxxEvent :xxxListener

Register the listeners()

Trigger the source()

Construct an xxxEvent object()

eventHandler(xxxEvent)


ControlListener Classes which implement this interface provide methods that deal with the events that are generated by moving and resizing controls.DisposeListener Classes which implement this interface provide a method that deals with the event that is generated when a widget is disposed.

DragDetectListener Classes which implement this interface provide methods that deal with the events that are generated when a drag gesture is detected.

ExpandListener Classes which implement this interface provide methods that deal with the expanding and collapsing of ExpandItems.FocusListener Classes which implement this interface provide methods that deal with the events that are generated as controls gain and lose focus.

HelpListenerClasses which implement this interface provide a method that deals with the event that is generated when help is requested for a control, typically when the user presses F1.

KeyListenerClasses which implement this interface provide methods that deal with the events that are generated as keys are pressed on the system keyboard.

MenuDetectListenerClasses which implement this interface provide methods that deal with the events that are generated when the platform-specific trigger for showing a context menu is detected.

MenuListener Classes which implement this interface provide methods that deal with the hiding and showing of menus.ModifyListener Classes which implement this interface provide a method that deals with the events that are generated when text is modified.MouseListener Classes which implement this interface provide methods that deal with the events that are generated as mouse buttons are pressed.MouseMoveListener Classes which implement this interface provide a method that deals with the events that are generated as the mouse pointer moves.

MouseTrackListenerClasses which implement this interface provide methods that deal with the events that are generated as the mouse pointer passes (or hovers) over controls.

MouseWheelListener Classes which implement this interface provide a method that deals with the event that is generated as the mouse wheel is scrolled.

PaintListenerClasses which implement this interface provide methods that deal with the events that are generated when the control needs to be painted.

SelectionListenerClasses which implement this interface provide methods that deal with the events that are generated when selection occurs in a control.

ShellListener Classes which implement this interface provide methods that deal with changes in state of Shells.

TouchListenerClasses which implement this interface provide methods that deal with the events that are generated as touches occur on a touch-aware input surface.

TraverseListenerClasses which implement this interface provide a method that deals with the events that are generated when a traverse event occurs in a control.

TreeListener Classes which implement this interface provide methods that deal with the expanding and collapsing of tree branches.

VerifyListenerClasses which implement this interface provide a method that deals with the events that are generated when text is about to be modified.



ControlAdapter This adapter class provides default implementations for the methods described by the ControlListener interface.ControlEvent Instances of this class are sent as a result of controls being moved or resized.DisposeEvent Instances of this class are sent as a result of widgets being disposed.DragDetectEvent Instances of this class are sent as a result of a drag gesture.ExpandAdapter This adapter class provides default implementations for the methods described by the ExpandListener interface.ExpandEvent Instances of this class are sent as a result of ExpandItems being expanded or collapsed.FocusAdapter This adapter class provides default implementations for the methods described by the FocusListener interface.FocusEvent Instances of this class are sent as a result of widgets gaining and losing focus.HelpEvent Instances of this class are sent as a result of help being requested for a widget.KeyAdapter This adapter class provides default implementations for the methods described by the KeyListener interface.KeyEvent Instances of this class are sent as a result of keys being pressed and released on the keyboard.MenuAdapter This adapter class provides default implementations for the methods described by the MenuListener interface.MenuDetectEvent Instances of this class are sent whenever the platform- specific trigger for showing a context menu is detected.MenuEvent Instances of this class are sent as a result of menus being shown and hidden.ModifyEvent Instances of this class are sent as a result of text being modified.MouseEvent Instances of this class are sent whenever mouse related actions occur.MouseTrackAdapter This adapter class provides default implementations for the methods described by the MouseTrackListener interface.PaintEvent Instances of this class are sent as a result of visible areas of controls requiring re-painting.SelectionAdapter This adapter class provides default implementations for the methods described by the SelectionListener interface.SelectionEvent Instances of this class are sent as a result of widgets being selected.ShellEvent Instances of this class are sent as a result of operations being performed on shells.TouchEvent Instances of this class are sent in response to a touch-based input source being touched.TraverseEvent Instances of this class are sent as a result of widget traversal actions.TreeAdapter This adapter class provides default implementations for the methods described by the TreeListener interface.TreeEvent Instances of this class are sent as a result of trees being expanded and collapsed.TypedEvent This is the super class for all typed event classes provided by SWT.VerifyEvent Instances of this class are sent as a result of widgets handling keyboard events



Display Instances of this class are responsible for managing the connection between

SWT and the underlying operating system. Their most important function is to implement the SWT event loop in terms of

the platform event model. They also provide various methods for accessing information about the

operating system, and have overall control over the operating system resources which SWT allocates.

Shell Represent the "windows" which the desktop or is managing.

Composite and Scrolled Composite Represent controls which are capable of containing other controls. A ScrolledComposite provides scrollbars and will scroll its content when the user uses the scrollbars.

Containers (1/2)


Group, Sash, Tab Folder Groups are subclass of composite that provide an

etched border with an optional title. A Sash represents a selectable user interface container

that allows the user to drag a rubber banded outline of the sash within the parent control.

Tab Folder allows the user to select a notebook page from set of pages.

Containers (2/2)

10

TIP: Calls to SWT methods that create widgets or modify currently visible widgets must be made from UI thread. Use Display.xxxExec!


Label

Button

Text

Combo

Simple Widgets


Menu and Toolbar

Table

Tree

Complex Widgets

12

TIP: the Eclipse Nebula project contains other custom Widgets and UI components.


class Widgets

widgets::Button

Drawable

widgets::Controlwidgets::Label

widgets::Menu

Item

widgets::MenuItem

widgets::Widget

Decorations

widgets::Shell

widgets::Sash

~menu

~parent~menu

~cascade

~lastActive

~activeMenu

Widget Class Hierarchy (1/3)


class Composite

widgets::Combo

widgets::Composite

WidgetDrawable

widgets::Control

widgets::Group

Item

widgets::TreeItem

widgets::TabFolder

Item

widgets::TabItem

widgets::Table

Item

widgets::TableItem

widgets::Text

Item

widgets::ToolItem

widgets::Tree

widgets::ToolBar

widgets::Scrollable

~items~parent

~tabList

~items

~items~currentItem

~parent

~control

~tabItemList

~parent~parent

~items~currentItem

~parent

~control



Main Methods void addListener(int eventType, Listener listener)

Adds the listener to the collection of listeners who will be notified when an event of the given type occurs. void dispose()

Disposes of the operating system resources associated with the receiver and all its descendants. Object getData(String key)

Returns the application defined property of the receiver with the specified name, or null if it has not been set. Display getDisplay()

Returns the Display that is associated with the receiver. Listener[] getListeners(int eventType)

Returns an array of listeners who will be notified when an event of the given type occurs. int getStyle()

Returns the receiver's style information. boolean isDisposed()

Returns true if the widget has been disposed, and false otherwise. boolean isListening(int eventType)

Returns true if there are any listeners for the specified event type associated with the receiver, and false otherwise. void notifyListeners(int eventType, Event event)

Notifies all of the receiver's listeners for events of the given type that one such event has occurred by invoking their handleEvent() method.

void removeListener(int eventType, Listener listener) Removes the listener from the collection of listeners who will be notified when an event of the given type occurs.

protected void

removeListener(int eventType, org.eclipse.swt.internal.SWTEventListener listener) Removes the listener from the collection of listeners who will be notified when an event of the given type occurs.

void setData(Object data) Sets the application defined widget data associated with the receiver to be the argument.

void setData(String key, Object value) Sets the application defined property of the receiver with the specified name to the given value.



Widget Class Styles

org.eclipse.swt.widgets.ButtonTOGGLE, ARROW, PUSH, RADIO, CHECK, FLAT,UP, DOWN, LEFT, RIGHT, CENTER

org.eclipse.swt.widgets.Combo DROP_DOWN, READ_ONLY, SIMPLE

org.eclipse.swt.widgets.CompositeNO_BACKGROUND, NO_FOCUS, NO_REDRAW_RESIZE,NO_MERGE_PAINTS, NO_RADIO_GROUP, EMBEDDED,DOUBLE_BUFFERED, UP

org.eclipse.swt.widgets.GroupSHADOW_IN, SHADOW_OUT, SHADOW_ETCHED_IN,SHADOW_ETCHED_OUT, SHADOW_NONE

org.eclipse.swt.widgets.LabelSEPARATOR, WRAP, SHADOW_IN, SHADOW_OUT,SHADOW_NONE, LEFT, RIGHT, CENTER,HORIZONTAL, VERTICAL

org.eclipse.swt.widgets.MenuBAR, DROP_DOWN, POP_UP, NO_RADIO_GROUP,LEFT_TO_RIGHT, RIGHT_TO_LEFT

org.eclipse.swt.widgets.MenuItem SEPARATOR, PUSH, RADIO, CHECK, CASCADEorg.eclipse.swt.widgets.Sash SMOOTH, HORIZONTAL, VERTICALorg.eclipse.swt.widgets.Scrollable H_SCROLL, V_SCROLL

org.eclipse.swt.widgets.ShellTOOL, NO_TRIM, RESIZE, TITLE, CLOSE, MIN, MAX,BORDER, ON_TOP, MODELESS, PRIMARY_MODAL,APPLICATION_MODAL, SYSTEM_MODAL

org.eclipse.swt.widgets.TabFolder TOP, BOTTOMorg.eclipse.swt.widgets.Table CHECK, MULTI, SINGLE, HIDE_SELECTION,FULL_SELECTION, VIRTUAL

org.eclipse.swt.widgets.TextMULTI, SINGLE, READ_ONLY, WRAP, SEARCH,PASSWORD, LEFT, RIGHT, CENTER

org.eclipse.swt.widgets.ToolBar WRAP, SHADOW_OUT, FLAT, RIGHT, HORIZONTAL,VERTICALorg.eclipse.swt.widgets.ToolItem DROP_DOWN, SEPARATOR, PUSH, RADIO, CHECKorg.eclipse.swt.widgets.Tree CHECK, MULTI, SINGLE, FULL_SELECTION, VIRTUAL

SWT Style Bits

16

TIP: not all styles are supported on all platforms.October 2013Copyright © 2013 Luca D’Onofrio – RCP Solutions

Fonts: manage operating system resources that define how text looks when it is

displayed. Fonts may be constructed by providing a device and either name, size and style information or a FontData object which encapsulates this data.

Colors: manage the operating system resources that implement SWT's RGB color

model. To create a color you can either specify the individual color components as integers in the range 0 to 255 or provide an instance of an RGB.

Images: graphics which have been prepared for display on a specific device. If loaded from a file format that supports it, an Image may have transparency. Images can be also created using SWT Canvas and GC Supported formats: GIF, JPG, PNG, BMP (Windows) and ICO (Windows)

TIP: these resources should be managed by a resource manager that creates them once and destroy them when the application exits.

Fonts, Colors, Images


Exercise


1. JFace Overview2. Model-View-Controller Concepts

a) A simple model

3. Viewers Architecturea) ContentProvider, LabelProvider,

DecoratingLabelProviderb) Viewer Sorter and Viewer Filterc) Drag & Dropd) Managing Selection

4. Putting all togheter

Agenda


SWT provides a direct interface to the native platform widgets, but it is limited to using simple data types: strings, numbers, images, …

This represents a limitation when dealing with object-oriented (OO) data that needs to be presented in lists, tables, trees, and text widgets.

This is where JFace viewers step in to provide OO wrappers around their associated SWT widgets.

JFace Overview (1/2)


JFace allows you to directly use your domain model objects: No need to manually decompose them into their basic

string, numerical, and image elements. The viewers provide adapter interface for handling domain

model object.

Main JFace Viewers Table Viewer Tree Viewer List Viewer Text Viewer

JFace Overview (2/2)


“Model–view–controller (MVC) is a software architecture pattern which separates the representation of information from the user's interaction with it.” (cit. Wikipedia)

A model is an object representing data or even activity, e.g. a database table or even some plant-floor production-machine process.

A view is some form of visualization of the state of the model.

A controller offers facilities to change the state of the model.

Model-View-Controller Concepts


class Model

Univ erse

Galaxy Cluster

Dark Matter

Galaxy

Star ClusterNebulae

Solar Systems Planets

Stars

SatellitesAsteroid

0..* 0..*

0..1

1..*1..*

0..*

1..* 1..*

1..*

A simple model


Input element An input element is the main object that the viewer is displaying (or

editing). A viewer must be able to handle a change of input element.

Content viewers A content viewer is a viewer that has a well defined protocol for obtaining

information from its input element. Content viewers use two specialized helper classes, the IContentProvider

and ILabelProvider, to populate their widget and display information about the input element. IContentProvider provides basic lifecycle protocol for associating a content

provider with an input element and handling a change of input element. More specialized content providers are implemented for different kinds of viewers.

ILabelProvider given the content of a viewer, it can produce the specific UI elements, such as names and icons, that are needed to display the content in the viewer.

A label provider can show more than just text and an image:

Viewers Architecture (1/4)


Filter and Sorter Filtering and sorting capability is handled by designating a viewer sorter

(ViewerSorter) and/or viewer filter (ViewerFilter) for the viewer.

Drag & Drop Viewers can handle D&D adding user defined classes known as DragSupport and

DropSupport Adding drag support to a viewer means that it enables the user to select any item

in the viewer with the mouse, and drag it into another viewer or another application, while the drop support verify if the viewer can accept a dragged element.

A Transfer provides a mechanism for converting between a java representation of data and a platform specific representation of data and vice versa

Managing Selection Viewers implement ISelectionProvider interface in order to provide selection to

other entities



class JFaceViewers

viewers::AbstractListViewer

viewers::AbstractTableViewer

viewers::AbstractTreeViewer

v iewers::CheckboxTableViewer

v iewers::CheckboxTreeViewer

viewers::ColumnViewer

viewers::ContentViewer«interface»v iewers::

IBaseLabelProv ider

«interface»v iewers::

IContentProv ider


IPostSelectionProv ider


ISelectionProv ider

v iewers::ListViewer

viewers::StructuredViewer

v iewers::TableTreeViewer

v iewers::TableViewer v iewers::TreeViewer

viewers::Viewer

v iewers::ViewerComparator

DropTargetAdapter

viewers::ViewerDropAdapter

viewers::ViewerFilter

v iewers::ViewerSorter

-contentProvider -sorter

-viewer

-labelProvider



class JFaceProv iders

v iewers::ArrayContentProv ider

EventManager

v iewers::BaseLabelProv ider

Viewer

viewers::ContentViewer

v iewers::DecoratingLabelProv ider


IBaseLabelProv ider


IContentProv ider


ILabelDecorator


ILabelProv ider


IStructuredContentProv ider


ITableLabelProv ider


ITreeContentProv ider


IViewerLabelProv ider

v iewers::LabelProv ider

-decorator

-instance

-labelProvider

-contentProvider



Putting All Together


http://www.eclipse.org/swt/widgets/ http://www.java2s.com/Tutorial/Java/0280__SWT/

Catalog0280__SWT.htm http://wiki.eclipse.org/JFace

References


Eclipse Training - SWT & JFace

Technology

Transcript of Eclipse Training - SWT & JFace