app/src/main/java/me/tatarka/support/job/sample/MainActivity.java
public void onReceivedStartJob(JobParameters params) {
        mShowStartView.setBackgroundColor(startJobColor);
        Message m = Message.obtain(mHandler, MSG_UNCOLOUR_START);
        mHandler.sendMessageDelayed(m, 1000L); // uncolour in 1 second.
        mParamsTextView.setText("Executing: " + params.getJobId() + " " + params.getExtras());
    }
public void onReceivedStartJob(JobParameters params) {
        mShowStartView.setBackgroundColor(startJobColor);
        Message m = Message.obtain(mHandler, MSG_UNCOLOUR_START);
        mHandler.sendMessageDelayed(m, 1000L); // uncolour in 1 second.
        mParamsTextView.setText("Executing: " + params.getJobId() + " " + params.getExtras());
    }
Receives callback from the service when a job has landed on the app. Colours the UI and post
a message to uncolour it after a second.