Question

I have an Android MapView in which i need to have a second layer of overlayed pins, over the one that the MapView already handles.

To accomplish this I have placed a FrameLayout over my MapView, and placed my pins as ImageViews in that Layout.

I have overridden the Draw() method of the ImageViews to update their position when the map moves (so that the pins move with it) like this:

public void draw(Canvas canvas) {
    if(mCoordinates != null && mapView != null){
        LayoutParams mParams = (LayoutParams)this.getLayoutParams();
        mapView.getProjection().toPixels(mCoordinates, newPosition);
        mParams.leftMargin = newPosition.x;
        mParams.topMargin = newPosition.y;
    }
    super.draw(canvas);
}

The problem: views are updating too slowly, so when I move the map the pins seem to lagg behind it.

Any insights on approach or implementation welcome

Answer 1

In the end we just mad a method that would order the overlays every time so that the big overlays were always painted first and the small ones over those.