Android 计时器实现

Android 计时器实现

• 一、CountDownTimer
• 二、handler.postDelayed
• 三、Handler + Timer + TimerTask
• 四、Handler + Thread.sleep()

 

一、CountDownTimer

    // 倒计时
    // 总时间 24 * 60 * 60 * 1000，间隔 1000s 回调一次 onTick
    CountDownTimer countDownTimer = new CountDownTimer(24 * 60 * 60 * 1000, 1000) {
        @Override
        public void onTick(long millisUntilFinished) {
            //单位天
            long day = millisUntilFinished / (1000 * 24 * 60 * 60);
            //单位时
            long hour = (millisUntilFinished - day * (1000 * 24 * 60 * 60)) / (1000 * 60 * 60);
            //单位分
            long minute = (millisUntilFinished - day * (1000 * 24 * 60 * 60) - hour * (1000 * 60 * 60)) / (1000 * 60);
            //单位秒
            long second = (millisUntilFinished - day * (1000 * 24 * 60 * 60) - hour * (1000 * 60 * 60) - minute * (1000 * 60)) / 1000;

            // 倒计时间隔回调
            Log.d("TAG", String.format("剩余时间：%d时%d分%d秒", hour, minute, second));
        }

        @Override
        public void onFinish() {
            // 倒计时结束时的回调
        }
    };

 

// 开始倒计时
countDownTimer.start();
        
// 取消倒计时
countDownTimer.cancel(); 

二、handler.postDelayed

private Handler handler = new Handler();

private Runnable runnable = new Runnable() {
    @Override
    public void run() {
        Log.d("TAG", "run: ");
        handler.postDelayed(this, 1000);
    }
};

// 启动计时器
handler.postDelayed(runnable, 1000);

// 停止计时器
handler.removeCallbacks(runnable);

 

三、Handler + Timer + TimerTask

private Timer timer = new Timer();
private Handler handler = new Handler(Looper.getMainLooper()){
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        Log.d("TAG", "handleMessage: timer");
    }
};

 

// 初始化计时器任务
TimerTask task = new TimerTask() {
    @Override
    public void run() {
        Message msg = handler.obtainMessage();
        msg.what = 1;
        msg.obj = "";
        msg.sendToTarget();
    }
};
// 启动计时器，延迟 1s 执行，每 2s 执行一次
timer.schedule(task, 1000, 2000);

 

// 停止计时器
timer.cancel();

 

四、Handler + Thread.sleep()

private Handler handler = new Handler(Looper.getMainLooper()){
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        Log.d("TAG", "handleMessage: ");
    }
};

 

new Thread(new Runnable() {
    @Override
    public void run() {
        while (true) {
            try {
                Thread.sleep(1000);
                Message msg = handler.obtainMessage();
                msg.what = 1;
                msg.obj = "";
                msg.sendToTarget();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}).start();