public boolean registerListener(BDAbstractLocationListener listener){
	boolean isSuccess = false;
	if(listener != null){
		client.registerLocationListener(listener);
		isSuccess = true;
	}
	return  isSuccess;
}
 

public void unregisterListener(BDAbstractLocationListener listener){
	if(listener != null){
		client.unRegisterLocationListener(listener);
	}
}