SimpleOnScaleGestureListener only receives onScaleBegin event

I'm trying to implement an onscalegesturelistener. My problem is, that the SimpleOnScaleGestureListener only receives the onScaleBegin event. The other events aren't being reported. I'm using a Nexus One for testing

public class ZoomHandler开发者_如何学C extends SimpleOnScaleGestureListener {

public float zoom;

public ZoomHandler(float zm) {
    this.zoom = zm;
}

public boolean onScale(ScaleGestureDetector arg0) {
    Log.i("SCALE", "onscale " + arg0.getScaleFactor());
    this.zoom *= arg0.getScaleFactor();

    // Don't let the object get too small or too large.
    this.zoom = Math.max(0.1f, Math.min(this.zoom, 5.0f));

    return true;
}

@Override
public boolean onScaleBegin(ScaleGestureDetector arg0) {
    Log.i("SCALE", "onscalebegin " + arg0.getScaleFactor());
    return false;
}

@Override
public void onScaleEnd(ScaleGestureDetector arg0) {
    Log.i("SCALE", "onscaleend " + arg0.getScaleFactor());
}

}

In the activity I'm doing this:

....

mScaleDetector = new ScaleGestureDetector(this , new ZoomHandler(this.zoom));

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

Thanks a lot

The return values of onScaleBegin() and onScale() control whether or not to continue with the sequence. If onScaleBegin() returns false, as yours does, none of the others will run.