android studio定时器

1.超时   

CountDownTimer第一个参数超时时间，第二个参数多久执行一次onTick(), 到达设定的超时时间执行onFinsh(),cancel取消超时计数，start重新开始（从零开始）。

 private CountDownTimer afterRunTimer=new CountDownTimer(2000,2000) {
        @Override
        public void onTick(long l) {


            LogUtil.d("TAG", "onTick: afterRunTimer");
        }

        @Override
        public void onFinish() {


            afterRunTimer.cancel();

            getActivity().runOnUiThread(new Runnable() {
                @Override
                public void run() {

                    LogUtil.d("TAG", "onFinish: afterRunTimer  readSN");
                    readSN();



                }
            });


        }
    };

 2.  

handler.postDelayed(myRunnable,1000);

 private Handler handler=new Handler();

    private Runnable myRunnable=new Runnable() {
        @Override
        public void run() {


            Log.d("TAG","myRunnable");
            //间隔时间循环执行
            //handler.postDelayed(myRunnable,1000);
        }
    };