onTouchEvent沒有被呼叫

使用 requestSensor 並且有註冊 registerRobotEventListener 裡面的 onTouchEvent,
可是碰觸手的時候並沒有收到onTouchEvent的callback, 我看底層log有顯示, 但是並沒有傳到app這層來.

mRobot.requestSensor(SENSOR_TOUCH) must be called after receiving onWikiServiceStart()

Ex:
mRobot.registerRobotEventListener(new RobotEventListener() {
@Override
public void onWikiServiceStart() {

 mRobot.requestSensor(SENSOR_TOUCH) ;

}
...