Gestures
Android use two classes
- MotionEvent
- Represent the movements
- TouchHandling
- To use the movement in the application
MotionEvent
The structure is
- Action Code
- State change that occurred
- Action Values
- Position and movement properties (time, source, location)
Rules
- Touches go down one at a time
- touches move as a group
- Come up one at a time or are cancelled
Methods
- getActionMasked()
- Return the action code associated with the motion event getActionIndex
- getActionIndex()
- Return the index of the pointer associated with the action code
- getPointerId(int)
- return the stable id of the pointer
Pointer
- Individual touch sources
- Each pointer has a unique ID as long as it is active
- Each pointer has an index within the event
- MotionEvent can refer to multiple pointers
GestureDetector
Recognize common touch gestures (single tap, double tap, fling)
To use it:
- Create a GestureDector that implements OnGestureListener interface
- When the activity is touch will recieve calls to onTouchEvent()
- The method delegates to GestureDetector.OnGestureListener
GestureBuilder
Lets create and save gestures
- GestureLibraries load the gestures in runtime
- GestureBuilder stores gestures in
- /mnt/sdcard/gestures
To user it:
- Include GestureOverlayView in the layout
- Intercepts user gestures and invoke application code
- Copy the file from /mnt/sdcard/gestures to /res/draw directory
Comentarios
Publicar un comentario