倒计时时间的处理

private class MainHandler extends Handler {        @Override        public void handleMessage(Message msg) {                        long now = SystemClock.elapsedRealtime();                        long delta = now - Receiver.ccCall.base;                        long seconds = (delta + 500) / 1000;  // round to nearest                        long minutes = seconds / 60;                        long hours = minutes / 60;                        long remainderMinutes = minutes - (hours * 60);                        long remainderSeconds = seconds - (minutes * 60);                        String secondsString = Long.toString(remainderSeconds);                        if (secondsString.length() < 2) {                            secondsString = "0" + secondsString;                        }                        String minutesString = Long.toString(remainderMinutes);                        if (minutesString.length() < 2) {                            minutesString = "0" + minutesString;                        }                        String text = minutesString + ":" + secondsString;                        if (hours > 0) {                            String hoursString = Long.toString(hours);                            if (hoursString.length() < 2) {                                hoursString = "0" + hoursString;                            }                            text = hoursString + ":" + text;                        }                        mRecordingTimeView.setText(text);                                                                                             mVideoPreview.invalidate();                        mHandler.sendEmptyMessageDelayed(UPDATE_RECORD_TIME, 1000);         }    };

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