求高人指点，关于android的timepickerdialog

Question

public  Dialog onCreateDialog(int id)
{
if(id==0)
{
 Calendar c2 = Calendar.getInstance();
            return new TimePickerDialog(this, new OnTimeSetListener() {
                @Override
                public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                 TextView  txm = (TextView)findViewById(R.id.txm);
                   txm.setText(String.valueOf(hourOfDay)+":"+String.valueOf(minute));
                
          }            }, c2.get(Calendar.HOUR), c2.get(Calendar.MINUTE), true); }
return null;