Xamarin 计划通知在android 9.0中不起作用

每当我在本地通知代码中使用Alarm Manager时，它在Android 8.0及以下版本中都可以正常工作。但是 它不适用于Android 9.0版

报警管理器代码：：

    var intent = CreateIntent(id);
        var localNotification = new LocalNotification();
        localNotification.Title = title;
        localNotification.Body = body;
        localNotification.Id = id;
        localNotification.NotifyTime = notifyTime;

        if (_notificationIconId != 0)
        {
            localNotification.IconId = _notificationIconId;
        }
        else
        {
            localNotification.IconId = Resource.Drawable.notification_bg;
        }

        var serializedNotification = SerializeNotification(localNotification);
        intent.PutExtra(ScheduledAlarmHandler.LocalNotificationKey, serializedNotification);

        Random generator = new Random();
        _randomNumber = generator.Next(100000, 999999).ToString("D6");

        var pendingIntent = PendingIntent.GetBroadcast(Application.Context, Convert.ToInt32(_randomNumber), intent, PendingIntentFlags.Immutable);
        var alarmManager = GetAlarmManager();
        alarmManager.Set(AlarmType.RtcWakeup, totalMilliSeconds, pendingIntent);

PendingIntent pendingIntent = PendingIntent.GetActivity(Application.Context, pendingIntentId, intent, PendingIntentFlags.Immutable);

        NotificationCompat.Builder builder = new NotificationCompat.Builder(Application.Context, channelId)

            .SetVibrate(new long[] { 0, 100 })
            .SetPriority(1)
            .SetContentIntent(pendingIntent)
            .SetContentTitle(title)               
            .SetContentText(body)
            .SetWhen(totalMilliSeconds)               
            .SetSmallIcon(Resource.Drawable.notification_bg)
            .SetDefaults((int)NotificationDefaults.Sound | (int)NotificationDefaults.Vibrate);

Notification notification = builder.Build();
        manager.Notify(channelId, messageId, notification);

而且，当我使用ChannelID与Notification Manager实现相同的代码时。所以，通知就出现在 Android 9.0及以下版本。 但是，如果我想设置一个特定的传递时间来显示通知，那么它在这里不起作用。它能立即交付

通知管理器代码：：

    var intent = CreateIntent(id);
        var localNotification = new LocalNotification();
        localNotification.Title = title;
        localNotification.Body = body;
        localNotification.Id = id;
        localNotification.NotifyTime = notifyTime;

        if (_notificationIconId != 0)
        {
            localNotification.IconId = _notificationIconId;
        }
        else
        {
            localNotification.IconId = Resource.Drawable.notification_bg;
        }

        var serializedNotification = SerializeNotification(localNotification);
        intent.PutExtra(ScheduledAlarmHandler.LocalNotificationKey, serializedNotification);

        Random generator = new Random();
        _randomNumber = generator.Next(100000, 999999).ToString("D6");

        var pendingIntent = PendingIntent.GetBroadcast(Application.Context, Convert.ToInt32(_randomNumber), intent, PendingIntentFlags.Immutable);
        var alarmManager = GetAlarmManager();
        alarmManager.Set(AlarmType.RtcWakeup, totalMilliSeconds, pendingIntent);

PendingIntent pendingIntent = PendingIntent.GetActivity(Application.Context, pendingIntentId, intent, PendingIntentFlags.Immutable);

        NotificationCompat.Builder builder = new NotificationCompat.Builder(Application.Context, channelId)

            .SetVibrate(new long[] { 0, 100 })
            .SetPriority(1)
            .SetContentIntent(pendingIntent)
            .SetContentTitle(title)               
            .SetContentText(body)
            .SetWhen(totalMilliSeconds)               
            .SetSmallIcon(Resource.Drawable.notification_bg)
            .SetDefaults((int)NotificationDefaults.Sound | (int)NotificationDefaults.Vibrate);

Notification notification = builder.Build();
        manager.Notify(channelId, messageId, notification);

---

那么，有没有一种方法可以让我在Android 9.0及以下版本中实现这一点呢？

根据Android文档，自Android 6.0（API级别23）以来，计划报警要求一直没有改变。您似乎没有以正确的方式实现报警，正如您所见，有很多不同之处，您应该使用WorkManager进行计划：根据Android文档，自Android 6.0（API级别23）以来，计划报警要求没有改变。您似乎没有以正确的方式实施报警，正如您所看到的，有很多不同之处，您应该使用WorkManager进行计划：