如何在android studio中向CountDownTimer添加变量？

public class MyCountDownTimer extends CountDownTimer {
    private long remainingTime;

    public MyCountDownTimer(long millisInFuture, long countDownInterval) {
        super(millisInFuture, countDownInterval);
        remainingTime = millisInFuture;
    }

    public long getRemainingTime() {
        return remainingTime;
    }

    @Override
    public void onTick(long millisUntilFinished) {
        remainingTime = millisUntilFinished;
        // 在这里更新UI，显示剩余时间
    }

    @Override
    public void onFinish() {
        // 倒计时结束后的操作
    }
}

MyCountDownTimer countDownTimer = new MyCountDownTimer(60000, 1000);
countDownTimer.start();