android 倒计时

timer = new CountDownTimer(20000,1000) {//第一个参数是总时间数，第二个参数是时间间隔
			
			@Override
			public void onTick(long millisUntilFinished) {
				count.setText("还剩：" + millisUntilFinished / 1000 + "秒");
			}
			
			@Override
			public void onFinish() {
				count.setText("游戏开始");
			}
		}.start();