android pinch zoom

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

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Answer Outdated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

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().