You can get AM/PM from Timepicker using following method.
Timepicker is a viewgroup.That's why we can get its child view index 2 which demonstrates AM/PM is actually a button. So we can get its text.
 Mycallback=new OnTimeSetListener() {
        public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
        ViewGroup vg=(ViewGroup) view.getChildAt(0);
            Toast.makeText(TimePickerDemoActivity.this, hourOfDay+":"+minute+":"+((Button)vg.getChildAt(2)).getText().toString(), 5000).show();
        }
    };