Custom progress bar background

Question

I am trying to copy the design of these progress bars :

I have searched here and only found how to populate the progress bar using:

mProgress = (ProgressBar) findViewById(R.id.progress_bar);

     // Start lengthy operation in a background thread
     new Thread(new Runnable() {
         public void run() {
             while (mProgressStatus < 100) {
                 mProgressStatus = doWork();

                 // Update the progress bar
                 mHandler.post(new Runnable() {
                     public void run() {
                         mProgress.setProgress(mProgressStatus);
                     }
                 });
             }
         }
     }).start();

Please anyone have an idea how to change the progress bar background to as shown in the image above