How to use async task to control a view pager

Issue

I am trying to create an auto image slider using a view pager following some tutorials. I got everything working, but then I see

Choreographer: Skipped 1 frames! The application may be doing too much work on its main thread. and googled the error.`

You see, in my code, I have a timer and a handler that just delay the code for 3 seconds and then slides the view pager to the next image. I confirmed with a friend and after hours of searching, there was nothing else that was doing too much work on the main thread.

So searching on stack overflow about the problem, I see that a lot of developers suggested using AsyncTask to do some stuff in background and then update, which might actually be a perfect solution here. But then I realised that I know nothing about AsyncTask. I went to the android developers reference and saw some tutorials, but I was unable to find something that'll fit into my solution.

I saw a lot of tutorials about image downloading, but they are by far, not what I'm concerned with. I am only concerned with controlling the view pager to move to the next slide.

Here is the part where I control my view pager to slide:

// Auto start of viewpager
        final Handler handler = new Handler();
        final Runnable Update = new Runnable() {
            public void run() {
                if (currentPage == NUM_PAGES) {
                    currentPage = 0;
                }
                mPager.setCurrentItem(currentPage++, true);
            }
        };
        Timer swipeTimer = new Timer();
        swipeTimer.schedule(new TimerTask() {
            @Override
            public void run() {
                handler.post(Update);
            }
        }, 3000, 3000);

How do I incorporate this code into an AsyncTask?

For reference, I used this tutorial.

Solution

Runnable is a seprate worker thread, it has no interaction with main thread. When you are handling ui elements, use runOnUiThread. example.

     runOnUiThread(new Runnable() {
            @Override
            public void run() {
                if (currentPage == NUM_PAGES) {
                    currentPage = 0;
                }
                mPager.setCurrentItem(currentPage++, true);
            }
        });

or

runOnUiThread(){
 mPager.setCurrentItem(currentPage++, true);
}   

Answered By - ankur uniyal