Android: add overlay to MapView?

I have subclassed Overlay as LandMarkOverlay (and implemented an onTap(GeoPoint) method).

In the main activity I do this:

    setContentView(R.layout.main);

    MapView mapView = (MapView) findViewById(R.id.mapview);
    mapView.setBuiltInZoomControls(true);
    开发者_StackOverflow中文版landmarkOverlay = new LandmarkOverlay();

    //add the landmarkOverlay to the list
    mapView.getOverlays().add(landmarkOverlay);

What else do I need to do so that when the user taps the screen, landmarkOverlay's onTap(GeoPoint) method gets called?

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It should get called. I assume your method is onTap(GeoPoint point, MapView mapView)?