devinc13

// getImage returns Observable<Bitmap>
// getAnotherImage returns Observable<Bitmap>

Subscription subscription = Observable.merge(getImage(), getAnotherImage())
    .collect(new ArrayList<Bitmap>(), new Action2<List<Bitmap>, Bitmap>() {
        @Override
        public void call(List<Bitmap> output, Bitmap input) {
            output.add(input);
        } 
    })

devinc13

// getImage returns Observable<Bitmap>
// getAnotherImage returns Observable<Bitmap>

Subscription subscription = Observable.merge(getImage(), getAnotherImage())
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(imageObserver);

// The imageObserver’s onNext will get called twice, with a bitmap each time, followed by 
// onComplete letting you know both bitmaps are done

devinc13

// getImageNetworkCall returns Observable<Bitmap>

Subscription subscription = getImageNetworkCall()
    .map(new Func1<Bitmap, BitmapDrawable>() {
        @Override
        public BitmapDrawable call(Bitmap bitmap) {
            // Convert Bitmap to BitmapDrawable
        }
    })
    .subscribeOn(Schedulers.io())

devinc13

public Observable<Bitmap> getImageNetworkCall() {
    // Insert network call here!
}

Subscription subscription = getImageNetworkCall()
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(new Observer<Bitmap>() {

        @Override

devinc13

private class NetworkCallTask extends AsyncTask<String, Void, int> {
    protected void onPreExecute() {
        // Perform setup - runs on user interface thread
    }

    protected int doInBackground(Void… param) {
        // Insert network call here!
    }

 protected void onProgressUpdate(String… values) {

devinc13

private Handler handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
        // Update user interface
    }
}

Runnable runnable = new Runnable() {
    public void run() {
        // Insert network call here!

devinc13

Runnable runnable = new Runnable() {
    public void run() {
        // Insert network call here!
    }
};
Thread mythread = new Thread(runnable);
mythread.start();

devinc13

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Insert network call here!
}