android 三种定时器的写法

一、 使用Timer 和 TimerTask
Timer timer = new Timer();
MyTimerTask timerTask = new MyTimerTask();
timer.schedule(timerTask, 3000, 1); // 延迟3秒钟,执行1次
//timer.cancel();// 取消

class MyTimerTask extends TimerTask {
	@Override
	public void run() {
                //这里不能处理UI操作
		// do something
	}
}
	
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二、采用Handler的sendMessageDelayed(Message, long)
public void startAutoFlowTimer() {
	handler = new Handler() {
		@Override
		public void handleMessage(Message msg) {
			// do something

			Message message = handler.obtainMessage(0);
			sendMessageDelayed(message, 1000);
		}
	};

	Message message = handler.obtainMessage(0);
	handler.sendMessageDelayed(message, 1000);
}

handler.removeMessages(0) //结束调用

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三、采用Handler的postDelayed(Runnable, long) 方法,这个实现比较简单一些：
1. Handler handler=new Handler();
Runnable runnable=new Runnable(){
	@Override
	public void run() {
		// do something
		handler.postDelayed(this, 2000); //在这里实现每两秒执行一次
	}
};

handler.postDelayed(runnable, 2000);//启动,两秒后执行runnable.

handler.removeCallbacks(runnable);  //停止

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//延迟执行
// 设置异步线程,
Handler handler = new Handler() {
	public void handleMessage(Message msg) { // handle message
		switch (msg.what) {
		case 1:
			//ui 方法
		}
		super.handleMessage(msg);
	}
};

Message message = handler.obtainMessage(1);
handler.sendMessageDelayed(message, 3000); // 发送message,3秒后隐藏提示框

评论

1 楼 androidwifi 2016-03-13  

sendMessageDelayed 不能实现循环, 看看这个方法的含义就知道了