AlarmManager警報未在分鍾的變化中完全啟動

Question

我正在制作一個鬧鍾，盡管使用了精確的鬧鍾，但它並不是在一分鍾的變化開始的：

例如，我設置為7:30，它將在7:30:00-7:31之間開始（無法檢查確切時間）。

我這樣撥打警報：

// Create the alarm
CustomAlarmManager alarmManager = new CustomAlarmManager(getActivity());
alarmManager.scheduleRepeatingAlarm(getActivity(), alarmID, alarmHour, alarmMinute);

運行此功能以創建警報：

public void scheduleRepeatingAlarm(Context context, int alarmID, int alarmHour, int alarmMinute) {

    // Create an intent to go to the notifications reciever class
    Intent intent = new Intent(context, AlarmNotificationReciever.class);

    // Bundle information and add to the intent for use later
    Bundle extras = new Bundle();
    extras.putInt("AlarmId", alarmID);
    extras.putInt("AlarmHour", alarmHour);
    extras.putInt("AlarmMinute", alarmMinute);
    intent.putExtras(extras);

    // Create a pending intent for the alarm id and intent
    PendingIntent pIntent = PendingIntent.getBroadcast(context,
            alarmID, intent, PendingIntent.FLAG_CANCEL_CURRENT);

    // Create a calender variable with the time for the alarm
    Calendar calender = Calendar.getInstance();
    calender.set(Calendar.HOUR_OF_DAY, alarmHour);
    calender.set(Calendar.MINUTE, alarmMinute);

    // Create a variable for the current alarm time
    LocalTime currentAlarmTime = LocalTime.parse(alarmHour+":"+alarmMinute+":"+"00");

    // Create a variable for the local time
    LocalTime localDeviceTime = LocalTime.now();

    // If the alarm has already elapsed today add one day to it so it runs for tomorrow
    if (localDeviceTime.isAfter(currentAlarmTime)) {

        calender.add(Calendar.DATE, 1);
        System.out.println("The time of day for the alarm has already past rescheduling for tomorrow");
    }

    // For the different versions of operating system set off a single shot alarm
    if(Build.VERSION.SDK_INT >= 23) {
        mAlarmManager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP,
                calender.getTimeInMillis(), pIntent);
    } else if(Build.VERSION.SDK_INT >= 19) {
        mAlarmManager.setExact(AlarmManager.RTC_WAKEUP, calender.getTimeInMillis(), pIntent);
    } else {
        mAlarmManager.set(AlarmManager.RTC_WAKEUP, calender.getTimeInMillis(), pIntent);
    }
}

我假設問題出在這里：

Calendar calender = Calendar.getInstance();
calender.set(Calendar.HOUR_OF_DAY, hour);
calender.set(Calendar.MINUTE, minute);

而在設置警報時此行：

mAlarmManager.setExact(AlarmManager.RTC_WAKEUP, calender.getTimeInMillis(), pIntent);

但是我不確定為什么那不是從分鍾的改變開始的。

謝謝你的幫助

Answer 1

Calendar.getInstance()返回設置為當前時間（和日期）的Calendar實例。

您正在設置此Calendar實例的HOUR_OF_DAY和MINUTE字段，但是SECOND字段仍具有其初始值，這就是這種行為的原因。

更改以下內容：

Calendar calender = Calendar.getInstance();
calender.set(Calendar.HOUR_OF_DAY, hour);
calender.set(Calendar.MINUTE, minute);

對此：

Calendar calender = Calendar.getInstance();
calender.set(Calendar.HOUR_OF_DAY, hour);
calender.set(Calendar.MINUTE, minute);
calendar.set(Calendar.SECOND, 0);