public class UiLoop {

    private Handler h;
    private AtomicBoolean breakLoop;

    @UiThread
    public UiLoop() {

        if (Looper.myLooper() != Looper.getMainLooper()) {
            throw new RuntimeException("Not called on ui thread!");
        }

        h = new Handler();
        breakLoop = new AtomicBoolean(false);
    }

    /**
     * Break out of the loop on the next iteration.
     */
    public void breakLoop() {
        this.breakLoop.set(true);
    }


    /**
     * @param workers    A Deque of runnables to execute sequentially.
     * @param delay The delay between executing the runnables. This is excluding the time it
     *              takes for the runnable to complete.
     */
    @UiThread
    public void loop(Deque<Runnable> workers, int delay) {

        if (Looper.myLooper() != Looper.getMainLooper()) {
            throw new RuntimeException("Not called on ui thread!");
        }

        if (workers.isEmpty()) return;

        if (breakLoop.get()) return;

        final Runnable first = workers.removeFirst();
        h.post(first);
        workers.addLast(first);
        h.postDelayed(() -> loop(workers, delay), delay);

    }
}