android - How to zoom ViewGroup? -

i need create view user can scale. list of components show in view pager. cant scaling in activity. thats why created custom view extends relativelayout.

public class jsonrelativelayout extends relativelayout {  private scalegesturedetector mscaledetector; private float mscalefactor = 1.f;  public jsonrelativelayout(context context) {     super(context);     mscaledetector = new scalegesturedetector(context, new scalelistener());  }  public jsonrelativelayout(context context, attributeset attrs) {     super(context, attrs);     mscaledetector = new scalegesturedetector(context, new scalelistener()); }  public jsonrelativelayout(context context, attributeset attrs, int defstyleattr) {     super(context, attrs, defstyleattr);     mscaledetector = new scalegesturedetector(context, new scalelistener()); }  @override public boolean ontouchevent(motionevent event) {     mscaledetector.ontouchevent(event);     return true; }  @override public void ondraw(canvas canvas) {     super.ondraw(canvas);      canvas.save();     canvas.scale(mscalefactor, mscalefactor);     //...     //your ondraw() code     //...     canvas.restore(); }  private class scalelistener extends simpleonscalegesturelistener {     @override     public boolean onscale(scalegesturedetector detector) {         mscalefactor *= detector.getscalefactor();          // don't let object small or large.         mscalefactor = math.max(0.1f, math.min(mscalefactor, 5.0f));          invalidate();         return true;     }  } 

but method onscale not work. , don`t know why.

to zoom view group need extend scrollview , override dispatchtouchevent , dispatchdraw.