Respond to a user touching the screen twice quickly

  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.ui.component.Dialog
  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 for the occurrence of a TouchGesture.TAP event and that TouchGesture.getTapCount returns 2.
    protected boolean touchEvent(TouchEvent message) {
       switch(message.getEvent()) {
          case TouchEvent.GESTURE:
             TouchGesture gesture = message.getGesture();
             switch(gesture.getEvent()) {
                case TouchGesture.TAP:
                   if(gesture.getTapCount() == 2) {
                      Dialog.alert("Double tap occurred");
                      return true;
                   }
              }
       }
     return false;
    }   

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