AsyncTask Android

Question

I want to run 2 method simultaneously. However it show only the output of second method. Can you help me?

    new AsyncTask<Void, Void, Bitmap>() {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

        }
        @Override
        protected Bitmap doInBackground(Void... params) {

            Run1(); 
            Run2();

            return currentBitmap;
        }
        @Override
        protected void onPostExecute(Bitmap bitmap) {
            super.onPostExecute(bitmap);
            if(bitmap!=null) {

                loadImageToImageView();
            }
        }
    }.execute();

Answer 1

Strategy depends on your tasks.

Don't use AsyncTask for simultaneous jobs, because by default it executed serially.

Your first try can be java Threads, if you don't need UI modification.

You can post results to UI thread by

• Activity.runOnUiThread(Runnable)
• View.post(Runnable)
• View.postDelayed(Runnable, long)

To process bitmap image consider to use HandlerThread .

Answer 2

You can Use Two Seprate Threads

// Create two threads:

Thread thread1 = new Thread() {
public void run() {
    Run1();
}

};

Thread thread2 = new Thread() {
public void run() {
  Run2();
}

};

// Start the both threads.
 thread1.start();
 thread2.start();

// Wait for them both to finish
thread1.join();
thread2.join();

Answer 3

Always execute your async tasks on Thread pool

new AsyncTask<Void, Void, Bitmap>() {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

    }
    @Override
    protected Bitmap doInBackground(Void... params) {

        Run1(); 
        Run2();

        return currentBitmap;
    }
    @Override
    protected void onPostExecute(Bitmap bitmap) {
        super.onPostExecute(bitmap);
        if(bitmap!=null) {

            loadImageToImageView();
        }
    }
}.executeOnExecutors(AsyncTask.THREAD_POOL_EXECUTOR);

Let me know if it works.

Answer 4

Try this

new AsyncTask<Void, Void, Bitmap>() {

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

    }
    @Override
    protected Bitmap doInBackground(Void... params) {

        Run1(); 
        Run2();

        return currentBitmap;
    }
    @Override
    protected void onPostExecute(Bitmap bitmap) {
        super.onPostExecute(bitmap);
        if(bitmap!=null) {

            loadImageToImageView();
        }
    }
}.executeOnExecutors(AsyncTask.THREAD_POOL_EXECUTOR);