Problem building app bundle with latest Google Mobile ads library

Unity Engine
, ,
1

I am using Unity editor version 2021.3.24f1 and Google Mobile ads 8.1.0. When I try to generate an app bundle, I get the following error:

Execution failed for task ‘:launcher:minifyReleaseWithProguard’.

java.io.IOException: Can’t read [C:.….gradle\caches\transforms-2\files-2.1\22478dd874d113db50106831ca8005f0\googlemobileads-unity-runtime.jar(;;;;;;;**.class)]
(Can’t process class [com/google/unity/ads/AdNetworkExtras.class] (Unsupported version number [55.0] (maximum 54.0, Java 10)))

I am using the Unity built-in version of JDK so I assume that the problem is with the Google Mobile ads version. I tried the solutions suggested for similar issues but they did not fix the problem.

Can someone help?

2

Can you try enabling R8 from build settings? unfortunately, I can’t reproduce it. If possible send me a sample project.

3

Thanks for the reply. I tried that - it works but I the app gets stuck when run (loading) and the log shows the following error:

AndroidJavaException: java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/activity/result/ActivityResultLauncher;
java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/activity/result/ActivityResultLauncher;
at java.lang.reflect.Executable.getParameterTypesInternal(Native Method)
at java.lang.reflect.Method.getParameterTypes(Method.java:186)
at java.lang.Class.getDeclaredMethods(Class.java:1915)
at com.unity3d.player.ReflectionHelper.getMethodID(Unknown Source:26)
at com.unity3d.player.UnityPlayer.nativeRender(Native Method)
at com.unity3d.player.UnityPlayer.access$500(Unknown Source:0)
at com.unity3d.player.UnityPlayer$e$1.handleMessage(Unknown Source:114)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at com.unity3d.player.UnityPlayer$e.run(Unknown Source:20)
Caused by: java.lang

I understand that the problem is that the ActivityResultLauncher is not found, probably because it gets removed by R8. Is there a fix to this?

4

Possible but not sure. Pass me a sample unity project to look into.

5

Thank you.

How can I send a sample Unity project? What do you need exactly?

My project is using the default gradle and proguard files… Should I use a custom Proguard file and enter commands to keep the above library?

6

well, you need to try creating a proguard file with keep options for the classes it states as missing.
Just upload the same project somewhere and pass me the link. I just need a way to reproduce on my end to see what solution fits.

7

I tried different things to fix the problem. I even created a new project and copied assets, code and settings to it (from the project that has the problem) and I still have the same issue. When I run a development build on the device it works correctly. Therefore, the problem is that R8 somehow removes or obfuscates the ActivityResultLauncher class.

I modified the proguard file (Assets\Plugins\Android\proguard-user.txt) with the following entries but it still does not work. Is there anything else I can try?

-keep class androidx.activity.result.ActivityResultLauncher { ; }
-keep class androidx.activity.result.* { *; }

-keep class * implements androidx.activity.result.ActivityResultCallback {
;
}
-keep class * extends androidx.activity.result.ActivityResultLauncher {
(…);
void launch(…);
}

8

I tried again and managed to fix the problem using the proguard rules above (not sure what was the problem before). It works in the new project I created but not on the old one. Also, when R8 is not enabled, I get the other problem with Java version mismatch (54/55). I am not an expert in Unity but it looks like there are a lot of things that need fixing. I decided to use Unity LTS to have a more stable version but it looks like the LTS versions also have issues…

9

Does anyone have any idea on how to fix this?

We are getting the same exception, but in our case it happens when we try to check Google Play Availability:

public static int GetGooglePlayAvailability()
{
   const string googleApiAvailabilityClassname = "com.google.android.gms.common.GoogleApiAvailability";
   AndroidJavaClass clazz = new AndroidJavaClass(googleApiAvailabilityClassname);
   AndroidJavaObject apiAvailabilityInstance = clazz.CallStatic<AndroidJavaObject>("getInstance");

   int value = apiAvailabilityInstance.Call<int>("isGooglePlayServicesAvailable", activity);

   // result codes from https://developers.google.com/android/reference/com/google/android/gms/common/ConnectionResult

   // 0 == success
   // 1 == service_missing
   // 2 == update service required
   // 3 == service disabled
   // 18 == service updating
      // 9 == service invalid
   return value;
}