Bind to service from new Context for configuration changes or bind from app context?

Question

I\'m trying to work out if bound service is appropriate for doing background work in my app. The requirements are that various application components can make web requests throu

Answer 1

I had a similar problem, where I have a Bound Service used in an Activity. Inside the activity I define a ServiceConnection, mConnection, and inside onServiceConnected I set a class field, syncService that's a reference to the Service:

private SynchronizerService syncService;

(...)

/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {

    @Override
    public void onServiceConnected(ComponentName className, IBinder service) {
        // We've bound to LocalService, cast the IBinder and get
        // LocalService instance
        Log.d(debugTag, "on Service Connected");
        LocalBinder binder = (LocalBinder) service;
        //HERE
        syncService = binder.getService();
        //HERE
        mBound = true;
        onPostConnect();
    }

    @Override
    public void onServiceDisconnected(ComponentName arg0) {
        Log.d(debugTag, "on Service Disconnected");
        syncService = null;
        mBound = false;
    }
};

Using this method, whenever the orientation changed I would get a NullPointerException when referencing the syncService variable, despite the fact the service was running, and I tried several methods that never worked.

I was about to implement the solution proposed by Sam, using a retained fragment to keep the variable, but first remembered to try a simple thing: setting the syncService variable to static.. and the connection reference is maintained when the orientation changes!

So now I have

private static SynchronizerService syncService = null;

...

/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {

    @Override
    public void onServiceConnected(ComponentName className, IBinder service) {
        // We've bound to LocalService, cast the IBinder and get
        // LocalService instance
        Log.d(debugTag, "on Service Connected");
        LocalBinder binder = (LocalBinder) service;
        //HERE
        if(syncService == null) {
            Log.d(debugTag, "Initializing service connection");
            syncService = binder.getService();
        }
        //HERE
        mBound = true;
        onPostConnect();
    }

    @Override
    public void onServiceDisconnected(ComponentName arg0) {
        Log.d(debugTag, "on Service Disconnected");
        syncService = null;
        mBound = false;
    }
};