在CountDownTimer中执行计时器计算是否有效 - ＆gt; onTick（）？

Question

我在TextView中显示可视倒计时，我想知道是否有更有效的方法来实现倒计时逻辑。我觉得在每个刻度上进行计算（即使计算很简单）可能会随着时间的推移消耗电池。

long now = Calendar.getInstance().getTimeInMillis();

Calendar midnight = new GregorianCalendar();
midnight.set(Calendar.HOUR_OF_DAY, 0);
midnight.set(Calendar.MINUTE, 0);
midnight.set(Calendar.SECOND, 0);
midnight.set(Calendar.MILLISECOND, 0);
midnight.add(Calendar.DAY_OF_MONTH, 1);

long deadline = midnight.getTimeInMillis();

long diff = deadline - now;

new CountDownTimer(diff, 1000) {

    public void onTick(long millisUntilFinished) {
        long days = TimeUnit.MILLISECONDS.toDays(millisUntilFinished);
        long hours = TimeUnit.MILLISECONDS.toHours(millisUntilFinished) - (days * 24);
        long minutes = TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished) - (days * 24 * 60) - (hours * 60);
        long seconds = TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) - (days * 24 * 60 * 60) - (hours * 60 * 60) - (minutes * 60);
        String fDays = String.format(Locale.FRANCE, "%d", days) + "J";
        String fHours = String.format(Locale.FRANCE, "%d", hours) + "h";
        String fMinutes = String.format(Locale.FRANCE, "%d", minutes) + "min";
        String fSeconds = String.format(Locale.FRANCE, "%d", seconds) + "s";
        fMinutes = (minutes < 10) ? "0" + fMinutes : fMinutes;
        fSeconds = (seconds < 10) ? "0" + fSeconds : fSeconds;

        String countDown = days > 0 ? fDays : "";
        countDown += (!countDown.isEmpty() || hours > 0) ? fHours : null;
        countDown += (!countDown.isEmpty() || minutes > 0) ? fMinutes : null;
        countDown += (!countDown.isEmpty() || seconds > 0) ? fSeconds : null;
        mTextView.setText(countDown);
    }

    public void onFinish() {
        mTextView.setText("done!");
    }
}.start();