Smooth zoom in Android MapView?

Issue

I have a MapView with one overlay. Overlay renders tile based map over the MapView. I use MapView.getZoomLevel() to retrieve current zoom level for Google map and for my tiles. Everything works just perfect, but only if user don't zoom the map using multitouch gestures. As I understand, the MapView control don't render actual tiles during zooming process, but just show stretched screen content. So, the question is - How to get this scale ratio which I can use to render my tiles exactly in same way as Google do?

Thank You!

Solution

Although the method MapView.getZoomLevel() isn't aligned with zoom changes animation and multitouche, the methods MapView.getProjection().fromPixels() and MapView.getProjection().fromPixels() are.

So you have several option to adress the issue. From the methos above, you can find the direct (x,y) coordinates (and size) where to render the tiles or you can find the zoom ration using something like:

int lonSpan = projection.fromPixels(0,mapView.getHeight()/2).getLongitudeE6() - 
    projection.fromPixels(mapView.getWidth(),mapView.getHeight()/2).getLongitudeE6();

which gives you the longitude span at map vertical center. Then, you divide the value after zoom starts from the value before zoom starts.

Regards.

Answered By - Luis