android pinch zoom

Question

My layout contains buttons, textviews, etc. Is it possible to implement pinch zoom in my layout?

Answer 1

Updated Answer

Code can be found here : official-doc

Answer Outdated

Check out the following links which may help you

Best examples are provided in the below links, which you can refactor to meet your requirements.

1. implementing-the-pinch-zoom-gestur

2. Android-pinch

3. GestureDetector.SimpleOnGestureListener

Answer 2

For android 2.2+ (api level8), you can use ScaleGestureDetector.

you need a member:

private ScaleGestureDetector mScaleDetector; 

in your constructor (or onCreate()) you add:

mScaleDetector = new ScaleGestureDetector(context, new OnScaleGestureListener() {     @Override     public void onScaleEnd(ScaleGestureDetector detector) {     }     @Override     public boolean onScaleBegin(ScaleGestureDetector detector) {         return true;     }     @Override     public boolean onScale(ScaleGestureDetector detector) {         Log.d(LOG_KEY, "zoom ongoing, scale: " + detector.getScaleFactor());         return false;     } }); 

You override onTouchEvent:

@Override public boolean onTouchEvent(MotionEvent event) {     mScaleDetector.onTouchEvent(event);     return true; } 

If you draw your View by hand, in the onScale() you probably do store the scale factor in a member, then call invalidate() and use the scale factor when drawing in your onDraw(). Otherwise you can directly modify font sizes or things like that in the onScale().