net.rim.device.api.lcdui
Class BlackBerryCanvas

java.lang.Object
  javax.microedition.lcdui.Displayable
      javax.microedition.lcdui.Canvas
          net.rim.device.api.lcdui.BlackBerryCanvas

All Implemented Interfaces:

Controllable

public abstract class BlackBerryCanvas
extends Canvas
implements Controllable

This class extends the functionality of the Canvas class to include full touch support and featured text input support.

Classes inheriting from this class can override the BlackBerryCanvas.touchEvent(net.rim.device.api.ui.TouchEvent) method to receive TouchEvent messages.

Applications using this class can call the #setInputHelper method to get the text input support.

The BlackBerryCanvas class implements Controllable and can be queried to retrieve BlackBerry-specific Controls. For instance, on devices which support a virtual keyboard, BlackBerryCanvas.getControl(String) may return a VirtualKeyboardControl object.

See Also:

TouchEvent, Field.touchEvent

Since:

BlackBerry API 4.7.0

Field Summary

Fields inherited from class javax.microedition.lcdui.Canvas

DOWN, FIRE, GAME_A, GAME_B, GAME_C, GAME_D, KEY_NUM0, KEY_NUM1, KEY_NUM2, KEY_NUM3, KEY_NUM4, KEY_NUM5, KEY_NUM6, KEY_NUM7, KEY_NUM8, KEY_NUM9, KEY_POUND, KEY_STAR, LEFT, RIGHT, UP

Constructor Summary
protected	BlackBerryCanvas() Creates a new instance of a BlackBerryCanvas.

Method Summary
Control	getControl(String controlType) Obtain the object that implements the specified Control interface.
Control[]	getControls() Obtain the collection of Controls from the object that implements this interface.
void	touchEvent(TouchEvent message) Indicates a touch event.

Methods inherited from class javax.microedition.lcdui.Canvas

getGameAction, getKeyCode, getKeyName, hasPointerEvents, hasPointerMotionEvents, hasRepeatEvents, hideNotify, isDoubleBuffered, keyPressed, keyReleased, keyRepeated, paint, pointerDragged, pointerPressed, pointerReleased, repaint, repaint, serviceRepaints, setFullScreenMode, showNotify, sizeChanged

Methods inherited from class javax.microedition.lcdui.Displayable

addCommand, getHeight, getTicker, getTitle, getWidth, isShown, removeCommand, setCommandListener, setTicker, setTitle

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BlackBerryCanvas

protected BlackBerryCanvas()

Creates a new instance of a BlackBerryCanvas.

See Also:

Canvas.Canvas()

Since:

BlackBerry API 4.7.0

Method Detail

touchEvent

public void touchEvent(TouchEvent message)

Indicates a touch event.

Parameters:

message - TouchEvent object containing various input parameters including the event type and touch coordinates.

Since:

BlackBerry API 4.7.0

getControls

public Control[] getControls()

Description copied from interface: Controllable

Obtain the collection of Controls from the object that implements this interface.

Since a single object can implement multiple Control interfaces, it's necessary to check each object against different Control types. For example:

Controllable controllable;
:
Control cs[];
cs = controllable.getControls();
for (int i = 0; i < cs.length; i++) {
if (cs[i] instanceof ControlTypeA)
doSomethingA();
if (cs[i] instanceof ControlTypeB)
doSomethingB();
// etc.
}


The list of Control objects returned will not contain any duplicates. And the list will not change over time.

If no Control is supported, a zero length array is returned.

Specified by:

getControls in interface Controllable

Returns:

the collection of Control objects.

See Also:

Controllable.getControls()

Since:

BlackBerry API 4.7.0

getControl

public Control getControl(String controlType)

Description copied from interface: Controllable

Obtain the object that implements the specified Control interface.

If the specified Control interface is not supported then null is returned.

If the Controllable supports multiple objects that implement the same specified Control interface, only one of them will be returned. To obtain all the Control's of that type, use the getControls method and check the list for the requested type.

Specified by:

getControl in interface Controllable

Parameters:

controlType - the class name of the Control. The class name should be given either as the fully-qualified name of the class; or if the package of the class is not given, the package javax.microedition.media.control is assumed.

Returns:

the object that implements the control, or null.

Throws:

IllegalArgumentException - Thrown if controlType is null.

See Also:

Controllable.getControl(String)

Since:

BlackBerry API 4.7.0