安卓|每天同一时间设置闹钟 |不工作

Question

在我的 Android 应用程序中，我会在每天凌晨 3 点启动一个命令，并使用 AlarmManager 和 setRepeating。当应用程序启动时，我这样做:

Calendar cal = Calendar.getInstance();
cal.set(Calendar.HOUR_OF_DAY, 3);
cal.set(Calendar.MINUTE, 0);
cal.set(Calendar.SECOND, 0);
Intent intent = new Intent(context, MyBroadcast.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context.getApplicationContext(), 1253, intent, PendingIntent.FLAG_UPDATE_CURRENT);
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);

这是MyBroadcast:

public class MyBroadcast extends BroadcastReceiver{
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub
        Log.d("ALARM","Alarm worked.");
    }
}

购买，而不是在 3 处运行命令，应用会立即运行命令。为什么？

Answer 1

当闹钟设置为已过日期时，它将立即触发，如果您不希望您可以创建一些逻辑以仅在当前时间早于凌晨 3 点时才在今天启动它，像这样的方法会起作用:

    Calendar now = Calendar.getInstance();
    Calendar cal = Calendar.getInstance();
    cal.set(Calendar.HOUR_OF_DAY, 3);
    cal.set(Calendar.MINUTE, 0);
    cal.set(Calendar.SECOND, 0);
    Intent intent = new Intent(context, MyBroadcast.class);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(context.getApplicationContext(), 1253, intent, PendingIntent.FLAG_UPDATE_CURRENT);
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    if (now.before(cal)) {
        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);
    } 
    else {
        cal.set(Calendar.DAY_OF_YEAR, now.get(Calendar.DAY_OF_YEAR) +1);
        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);   
    }

我们创建了另一个日历作为当前时间的引用，并检查我们是否在凌晨 3 点之前，如果不是，则仅在一天后调用闹钟。