Hey there! I see you're having trouble getting your custom notification content and Intent to work for your foreground service—instead it's showing that generic system message and linking to app info. Let's break down what might be going wrong and fix it.

Common Issues & Fixes #

1. Missing Notification Channel Setup (Android 8.0+) #

Starting with Android Oreo (API 26), you must create a notification channel for your CHANNEL_ID before posting any notifications. If you skip this step, the system might fall back to a default channel that overrides your custom content.

Add this code to initialize your channel (usually in your Application class or before calling startForeground):

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    NotificationChannel channel = new NotificationChannel(
        CHANNEL_ID,
        "Foreground Service Channel", // Custom channel name
        NotificationManager.IMPORTANCE_DEFAULT // Adjust importance as needed
    );
    channel.setDescription("Channel for foreground service notifications"); // Optional description
    NotificationManager notificationManager = getSystemService(NotificationManager.class);
    notificationManager.createNotificationChannel(channel);
}

2. Outdated PendingIntent Flags (Android 12+) #

On Android 12 (API 31) and later, creating a PendingIntent requires specifying either FLAG_IMMUTABLE or FLAG_MUTABLE. Using 0 as the flag can lead to unexpected behavior, including your Intent not being honored.

Update your PendingIntent creation line:

int flags = Build.VERSION.SDK_INT >= Build.VERSION_CODES.S ? PendingIntent.FLAG_IMMUTABLE : 0;
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, flags);

(Use FLAG_MUTABLE only if you need to modify the Intent later—most cases don't require this.)

3. Duplicate Flag Setting #

Your line notification.flags = notification.flags | Notification.FLAG_NO_CLEAR; is redundant because setOngoing(true) already makes the notification non-clearable. You can safely remove this line to clean up your code.

4. Missing Permissions #

• For Android 9 (API 28) and above: Add the FOREGROUND_SERVICE permission to your AndroidManifest.xml:

  <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
  

• For Android 13 (API 33) and above: You need to request the POST_NOTIFICATIONS permission dynamically (in addition to declaring it in the manifest):

  <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
  

  Then request it at runtime using ActivityResultContracts.RequestPermission.

Corrected Full Code #

Here's how your updated code should look with all fixes applied:

// First, create the notification channel (if needed)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    NotificationChannel channel = new NotificationChannel(
        CHANNEL_ID,
        "Foreground Service Channel",
        NotificationManager.IMPORTANCE_DEFAULT
    );
    channel.setDescription("Channel for our persistent service notification");
    NotificationManager notificationManager = getSystemService(NotificationManager.class);
    notificationManager.createNotificationChannel(channel);
}

// Build your Intent and PendingIntent with correct flags
Intent notificationIntent = new Intent(this, MyActivity.class);
int pendingIntentFlags = Build.VERSION.SDK_INT >= Build.VERSION_CODES.S 
    ? PendingIntent.FLAG_IMMUTABLE 
    : 0;
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, pendingIntentFlags);

// Build the notification
Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
    .setContentTitle(APP_NAME)
    .setContentText(NOTIFICATION_CONTENT)
    .setContentIntent(pendingIntent)
    .setOngoing(true)
    .setSmallIcon(R.drawable.your_notification_icon) // Don't forget this! Missing small icon can break notifications
    .build();

// Start the foreground service with your custom notification
startForeground(NOTIFICATION_ID, notification);

Critical Note: Don't Forget the Small Icon #

I also added setSmallIcon() to the builder—this is a required field for all notifications on Android. If you omit it, the system might again fall back to a default notification or fail to show yours entirely.

Why the Default System Notification Was Showing #

The generic "App is running..." message usually appears when the system can't properly process your custom notification (e.g., missing channel, missing small icon, invalid flags). By fixing these issues, your custom content and Intent should start working as expected.

内容的提问来源于stack exchange，提问作者rafvasq