android 如果当天的闹钟时间已过，则防止立即触发闹钟服务

Question

警报管理器的参考资料说

If the stated trigger time is in the past, the alarm will be triggered immediately.

我在申请中遇到了这个问题。这是我的警报管理器代码：

Intent myIntent = new Intent(getActivity(), DinnerAlarmReceiver.class);
                pendingDinnerIntent = PendingIntent.getBroadcast(getActivity(), 0, myIntent, 0);

                Calendar calendar = Calendar.getInstance();
                calendar.set(Calendar.HOUR_OF_DAY, hourOfDay);
                calendar.set(Calendar.MINUTE, minute);

                alarmManager.set(AlarmManager.RTC_WAKEUP,
                        calendar.getTimeInMillis(), pendingDinnerIntent);

这个问题有解决办法吗？

-----编辑-----

我写了一些代码来估计闹钟的设置时间是否早于当前时间。这是上面的部分并进行了相应的更改：

Calendar calendar = Calendar.getInstance();
                long currentTime = calendar.getTimeInMillis();
                calendar.set(Calendar.HOUR_OF_DAY, hourOfDay);
                calendar.set(Calendar.MINUTE, minute);
                long setTime = calendar.getTimeInMillis();
                Timestamp setTimestamp = new Timestamp(setTime);
                Timestamp currentTimestamp = new Timestamp(currentTime);
                if (setTimestamp.after(currentTimestamp))
                {
                    alarmManager.set(AlarmManager.RTC_WAKEUP,
                            calendar.getTimeInMillis(), pendingDinnerIntent);
                }
                else
                {
                }

如果 setTimestamp 在 currentTimestamp 之前，我应该 alarmManager 做什么？

Answer 1

您不需要创建 Timestamp。你可以用你的 Calendar.

Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.HOUR_OF_DAY, hourOfDay);
calendar.set(Calendar.MINUTE, minute);

if(calendar.before(Calendar.getInstance())) {
    calendar.add(Calendar.DATE, 1);
}

alarmManager.set(AlarmManager.RTC_WAKEUP,
    calendar.getTimeInMillis(), pendingDinnerIntent);

我还要提到，对于 KitKat，如果您的 targetSdkVersion 是 19 或以上，则 AlarmManager#set() 方法不准确。如果您希望闹钟在准确的时间触发，您需要使用 setExact*() 方法。