如何制作不弹出，只显示在通知列表中的 Android 本地通知？

Question

I am making a type of alarm app. I have a special alarm screen that I show when the alarm time comes. That works fine. But I also want there to be an entry in the notifications list if the user snoozes the alarm. But when I try to use a regular Notification using NotificationBuilder, it pops up on the screen at the same as my alarm activity (which is not full screen - uses transparency). There must be a way to get the notification into the list, so the user will see it there, but not have it pop up at alarm time.

Answer 1

You need to use a low priority for channel you created

NotificationManager.IMPORTANCE_LOW  or NotificationManager.IMPORTANCE_MIN 

From Android Oreo, you need to use notification channels for creating Notifications.

For Example : When you create a channel, with id "Alerts" , you can define its properties like, its importance , sound etc...

The various Importance Attributes used are as follows :

IMPORTANCE_DEFAULT: Default notification importance: shows everywhere, makes noise , but does not visually intrude. Constant Value: 3

IMPORTANCE_HIGH : Higher notification importance: shows everywhere, makes noise and peeks . May use full screen intents.

[This will keep showing over other apps and again like whatsapp message notification] This works so because of its importance. Constant Value: 4

IMPORTANCE_LOW Low notification importance: shows everywhere, but is not intrusive. Constant Value: 2

IMPORTANCE_MIN Min notification importance: only shows in the shade, below the fold. Constant Value: 1

So once you define a channels properties it could be changed by only the user through notification intent. Which i mentioned here : https://stackoverflow.com/a/54199316/7039593

Using a low priority / min min importance may solve your problem

Answer 2

This is done by setting the notification priority to MINIMUM. For example:

NotificationCompat.Builder b = new NotificationCompat.Builder(context, "MyReminder");
b.setPriority(NotificationCompat.PRIORITY_MIN);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    String id = MyApp.getNotificationChannel(context);
    b.setChannelId(id);
}

Note for Oreo and higher you need to also set the priority of the notification channel:

final private static String MyChannelID = "MyChannel_1";
private static NotificationChannel channel;

static private String getNotificationChannel(Context context) {
    // Create the NotificationChannel, but only on API 26+ because
    // the NotificationChannel class is new and not in the support library
    if (channel == null) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {

            CharSequence name = "My Reminders";
            String description = "My Reminders pre-scheduled using My app";
            int importance = NotificationManager.IMPORTANCE_MIN;
            channel = new NotificationChannel(MyChannelID, name, importance);
            channel.setDescription(description);
            channel.enableLights(true);
            // Sets the notification light color for notifications posted to this
            // channel, if the device supports this feature.
            channel.setLightColor(Color.RED);

            channel.enableVibration(true);

            // Register the channel with the system; you can't change the importance
            // or other notification behaviors after this
            getNotificationManager().createNotificationChannel(channel);
        }
    }
    return MyChannelID;
}


static public NotificationManager getNotificationManager() {
    Context context = App.getContext();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        return context.getSystemService(NotificationManager.class);
    }
    else {
        return (NotificationManager) context.getSystemService(context.NOTIFICATION_SERVICE);
    }
}

I didn't check the behavior of every priority, but MINIMUM and IMPORTANCE_MIN work. If you have more specific behaviors you want to get, you can look at the documentation and play with other priority levels.

Answer 3

you use setNotificationSilent()

like this:

new NotificationCompat.Builder(this)
    .setContentTitle("dasf")
    .setStyle(new NotificationCompat.BigTextStyle().bigText("adsf"))
    .setContentText(getText(R.string.text))
    .setSubText("adsf" + " " + getString(R.string.bdt))
    .setNotificationSilent()
    .setSmallIcon(R.drawable.ic_notification);