Unity中Firebase Messaging 4.4版仅显示默认通知图标求助

Hey Jonas, sorry to hear you're stuck with this default icon problem after updating to Firebase Messaging 4.4! Let's walk through what's likely changed and how to get your custom icons working again:

What Might Have Changed #

While the official docs don't explicitly call this out, Firebase Messaging 4.4 tightened up the validation for custom notification icon resources. The older 4.2 version was more lenient with how it parsed the icon parameter and loaded drawables, but the newer version enforces stricter Android resource naming and path rules.

Step-by-Step Fixes #

1. Verify Your Icon Resources #

First, make sure your icon files meet Android's requirements:

• File naming: Use all lowercase letters, no spaces or special characters (e.g., ic_notification_alert instead of NotificationIcon!). Android 10+ is case-sensitive with resource filenames, so even a capital letter mismatch can break loading.
• Format & dimensions: Use transparent-background PNGs or vector drawables. For best compatibility, include scaled versions in the appropriate drawable-*dpi folders (mdpi: 24x24px, hdpi: 36x36px, xhdpi: 48x48px, etc.) under Assets/Plugins/Android/AN_Res/res/.
• Path validation: Double-check that icons are placed directly in the correct drawable subfolders, no nested directories.

2. Adjust the icon Parameter in Your Notification Payload #

The way the icon parameter is parsed changed slightly. Try these formats depending on how you're sending notifications:

• For Firebase Console: When composing a notification, under the "Android Options" section, enter the exact resource name (without file extension, e.g., ic_notification) in the "Icon" field.
• For Server-side API: Use the android.notification.icon field with the resource name (you can optionally prefix with @drawable/, though it's usually not required):

  {
    "notification": {
      "title": "Your Title",
      "body": "Your Notification Content"
    },
    "android": {
      "notification": {
        "icon": "ic_notification"
      }
    },
    "token": "your-device-token"
  }
  

3. Update Your AndroidManifest.xml #

Even if you didn't need it before, adding a default notification icon meta-data can help the system resolve your custom icons correctly. Add this inside the <application> tag:

<meta-data
    android:name="com.google.firebase.messaging.default_notification_icon"
    android:resource="@drawable/ic_notification" />

This sets a fallback, but your notification payload's icon parameter should still override this if correctly specified.

4. Validate Resource Packing #

• For Unity projects: Open Player Settings > Android > Publishing Settings, and ensure the Assets/Plugins/Android/AN_Res/ directory is marked for inclusion (no exclusion rules applied).
• After building your APK, use Android Studio's APK Analyzer to check if your custom icons are present under res/drawable-* folders. If they're missing, your build pipeline isn't packaging them correctly.

5. Test Edge Cases #

• Try sending a notification with an icon you know works (e.g., the app's launcher icon name) to rule out payload issues.
• Test on different Android versions (especially Android 10+ and older devices) to see if the problem is version-specific.

Hope these steps get your custom notification icons showing up again! If you hit any snags, feel free to share more details about your setup (like your payload structure or icon file setup).

内容的提问来源于stack exchange，提问作者smokiespartakus