不要忘了BroadcastReceiver 注册的用法

BroadcastReceiver 是用来接收广播意图的服务组件，最普通的用法是，在androidmanifest.xml中注册相应的Intentfilter 的Action，
但是还有有另外一种方法就是：在代码中注册，一般用个service在后台运行时候,如下

	@Override
	public int onStartCommand(Intent intent, int flags, int startId) {
		Log.i("sys","start service");
		MyReceiver myReceiver = new MyReceiver();
		IntentFilter filter = new IntentFilter();
		
		filter.addAction(Intent.ACTION_SCREEN_ON);
		filter.addAction(Intent.ACTION_SCREEN_OFF);
		this.registerReceiver(myReceiver, filter);
		return super.onStartCommand(intent, flags, startId);
	}