Track an user with location based App

Question

I'm working on a Location based App. Here my requirement is I want to track a user location from my device like uber or Ly ft App. Example: If a pizza guy(User B) wants to deliver pizza to me(User A) then he can share his user id, so using that id, I can enter in my device and see his exact precise location. But I want to track him until I required so how to achieve this in code. Help me with the architecture if you have come across such scenario.

I can also achieve the above scenario, but my doubt is how can I show in map without refreshing each time when the user moves say for example two minutes once I want to check the Latitude and Longitude and update it in my map for the same user

Answer 1

Create a Thread, that asks a Handler to get the position a few times. You need to use a Handler, because the getMyLocation method can only be called from GUI Thread:

private class MyLocationThread extends Thread{
    @Override
    public void run() {
        int loops = 0;
        // we give the location search a minute 
        while(loops < 60){
            // we have to try it over a handler, because getMyLocation() has to be called from GUI Thread -_-
            _getMyLocationHandler.sendEmptyMessage(0);
            if(isInterrupted()){
                return;
            }
            // take a short nap before next try
            try {Thread.sleep(1000);} catch(Exception e){}
            loops++;
        }

    }
}

Here's what the Handler does:

private Handler _getMyLocationHandler = new Handler(){
    public void handleMessage(android.os.Message msg) {
        if(getMap().isMyLocationEnabled() && getMap().getMyLocation() != null){
            _locationWatcher.interrupt();
            drawCurrentImagePositions();
        }
    }
};