code: @Override
      public void onTimeChanged(int hour, int minute) {
          mCalendar.set(Calendar.HOUR_OF_DAY, hour);
          mCalendar.set(Calendar.MINUTE, minute);
  
          updateTimeTab();
      }
docs: <p>The callback used by the TimePicker to update {@code mCalendar} as
  the user changes the time. Each time this is called, we also update
  the text on the time tab to reflect the time the user has currenly
  selected.</p>
  <p>
  <p>Implements the {@link TimeFragment.TimeChangedListener}
  interface.</p>