How to fix Non-SDK interfaces usage on Android 9

Questions & Answers
1

Hi guys!

When I upload apk to Google, prelaunch reports give me warning on Android 9 devices:

Non-SDK interfaces usage.

What can cause this?

Im trying to update my game with target api 28.
My project only has two plugins:

Play games plugin for unity (sign in and cloud save games) and Unity IAP. Both are latest versions.

I also have usesCleartextTraffic=true inside my Android manifest (i read text from php page).
That’s all. Nothing special.

I have updayed to 2018.2.8f and latest SDK but nothing changes.
Im building with Gradle and Mono.

Please, give me some hints!

Thanks!

2

I run some test in Firebase Test Lab with Pixel2 API28. It says:

Your app uses 3 non-SDK interfaces, which are incompatible with Android P+. Take a look at the logs to see detailed stack traces. Sample of used non-SDK interfaces: 
Landroid/media/AudioSystem;->getPrimaryOutputFrameCount()I
Landroid/media/AudioSystem;->getPrimaryOutputSamplingRate()I
Ljava/lang/invoke/MethodHandles$Lookup;->(Ljava/lang/Class;I)V

Logs has bunch of messages like the following and I have no Idea what it all means;(

09-22 07:02:23.147: D/StrictMode(13069): StrictMode policy violation: android.os.strictmode.NonSdkApiUsedViolation: Landroid/media/AudioSystem;->getPrimaryOutputFrameCount()I
09-22 07:02:23.147: D/StrictMode(13069): 	at android.os.StrictMode.lambda$static$1(StrictMode.java:428)
09-22 07:02:23.147: D/StrictMode(13069): 	at android.os.-$$Lambda$StrictMode$lu9ekkHJ2HMz0jd3F8K8MnhenxQ.accept(Unknown Source:2)
09-22 07:02:23.147: D/StrictMode(13069): 	at com.unity3d.player.UnityPlayer.nativeRender(Native Method)
09-22 07:02:23.147: D/StrictMode(13069): 	at com.unity3d.player.UnityPlayer.c(Unknown Source:0)
09-22 07:02:23.147: D/StrictMode(13069): 	at com.unity3d.player.UnityPlayer$e$2.queueIdle(Unknown Source:72)
09-22 07:02:23.147: D/StrictMode(13069): 	at android.os.MessageQueue.next(MessageQueue.java:395)
09-22 07:02:23.147: D/StrictMode(13069): 	at android.os.Looper.loop(Looper.java:160)
09-22 07:02:23.147: D/StrictMode(13069): 	at com.unity3d.player.UnityPlayer$e.run(Unknown Source:32)
3

I’m getting this now too. I suspect that this is in Unity’s court to update because the things it is complaining about aren’t things we can control as far as I know.

4

I started getting this building with old Unity5 LTS. I posted about it here:

https://forum.unity.com/threads/google-play-api-warnings-started-today.676654/

Kurt