Blackberry JAVA DEVELOPMENT ENVIRONMENT - - DEVELOPMENT GUIDE Manual page 41

Development Guide
Respond to a scroll action
1. Import the following classes:
• net.rim.device.api.ui.TouchEvent
• net.rim.device.api.ui.TouchGesture
• net.rim.device.api.ui.Field
• net.rim.device.api.ui.Manager
• net.rim.device.api.ui.Screen
• net.rim.device.api.system.Display
• net.rim.device.api.ui.component.Dialog
• net.rim.device.api.ui.Screen
2. Create a class that extends the Manager class.
public class newManager extends Manager {
3. In your implementation of the touchEvent(TouchEvent message) method, check if the value
TouchEvent.getEvent() returns is equal to TouchEvent.MOVE.
protected boolean touchEvent(TouchEvent message) {
switch(message.getEvent()) {
case TouchEvent.MOVE:
return true;
}
return false;
}
Respond to a user touching the screen in two locations at the same time
1. Import the following classes:
• net.rim.device.api.ui.TouchEvent
• net.rim.device.api.ui.Field
• net.rim.device.api.ui.Manager
• net.rim.device.api.ui.Screen
2. Create a class that extends the Manager class, the Screen class, the Field class, or one of the Field subclasses.
public class newButtonField extends ButtonField {
3. In your implementation of the touchEvent(TouchEvent message) method, check if the following method
invocations return values greater than zero: TouchEvent.getX(1), TouchEvent.getY(1),
TouchEvent.getX(2), TouchEvent.getY(2).
protected boolean touchEvent(TouchEvent message) {
switch(message.getEvent()) {
case TouchEvent.MOVE:
if(message.getX(1) > 0 && message.getY(1) > 0) {
Touch screen events
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