Pinch to zoom with Osmdroid

Question

I\'ve written a mapping application which has two activities, one activity displays a Google Maps view, the other displays the equivalent view using osmdroid 3.0.5 jar.

Answer 1

Osmdroid has the functionality to zoom. You will need to setup a gesturelistener to check for the pinch action, at which point you should call the zoom function in osmdroid. I believe in osmdroid 3.0.5 it is something like

mOsm.getController.setZoomLevel(someNumber) (mOsm is an instance of the map view).

I have the zoom function working for the opposite pinch (you fingers start close together and then expand). I suggest using a MotionEvent (like you are currently doing) and doing something like this:

boolean finished = false;

@Override
public boolean onTouch(View v, MotionEvent e) {

    switch (e.getAction()) {

        case MotionEvent.ACTION_DOWN:
            finished = false;
            break;

        case MotionEvent.ACTION_MOVE:
            finished = false;
            break;

        case MotionEvent.ACTION_UP:
            //action is finishing at this point, so now I can do my refreshActionOnMap();
            if (!finished) 
                refreshActionOnMap();
            break;
    }
    return true;
}

The code I have added deals with the pinch - the finished boolean is something I implemented in my program to figure out when to refresh the map. That should help you out more.

Here is a further explanation of this.

If you are looking for something different, then try reading here. Android has been supporting the pinch action since June 2010 apparently.

Answer 2

MapView.setBuiltInZoomControls(true);
MapView.setMultiTouchControls(true);

Answer 3

Is it possible not to zoom to the map center but to the middle of users two finger.