Android Question NonSdkApiUsedViolation

[CaptKronos]

Just noticed that Google's Pre-Launch Report for my app has raised a "Usage of non SDK interfaces" issue when testing against an Android 9 device.

The logcat has recorded many instances of the violation with the following being an example chosen at random.

37315 09-27 10:53:49.854: D/StrictMode(12541): StrictMode policy violation: android.os.strictmode.NonSdkApiUsedViolation: Landroid/view/WindowManagerGlobal;->mViews:Ljava/util/ArrayList;
37316 09-27 10:53:49.854: D/StrictMode(12541):     at android.os.StrictMode.lambda$static$1(StrictMode.java:428)
37317 09-27 10:53:49.854: D/StrictMode(12541):     at android.os.-$$Lambda$StrictMode$lu9ekkHJ2HMz0jd3F8K8MnhenxQ.accept(Unknown Source:2)
37318 09-27 10:53:49.854: D/StrictMode(12541):     at java.lang.Class.getDeclaredField(Native Method)
37319 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.base.RootsOracle.a(RootsOracle.java:13)
37320 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.base.RootViewPicker$RootResultFetcher.a(RootViewPicker.java:5)
37321 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.base.RootViewPicker.a(RootViewPicker.java:37)
37322 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.ViewInteractionModule_ProvideRootViewFactory.get(ViewInteractionModule_ProvideRootViewFactory.java:10)
37323 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.base.ViewFinderImpl.a(ViewFinderImpl.java:10)
37324 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.ViewInteraction.a(ViewInteraction.java:58)
37325 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.ViewInteraction.a(ViewInteraction.java:94)
37326 09-27 10:53:49.854: D/StrictMode(12541):     at androidx.test.espresso.ViewInteraction$1.call(ViewInteraction.java:3)
37327 09-27 10:53:49.854: D/StrictMode(12541):     at java.util.concurrent.FutureTask.run(FutureTask.java:266)
37328 09-27 10:53:49.854: D/StrictMode(12541):     at android.os.Handler.handleCallback(Handler.java:873)
37329 09-27 10:53:49.854: D/StrictMode(12541):     at android.os.Handler.dispatchMessage(Handler.java:99)
37330 09-27 10:53:49.854: D/StrictMode(12541):     at android.os.Looper.loop(Looper.java:193)
37331 09-27 10:53:49.854: D/StrictMode(12541):     at android.app.ActivityThread.main(ActivityThread.java:6669)
37332 09-27 10:53:49.854: D/StrictMode(12541):     at java.lang.reflect.Method.invoke(Native Method)
37333 09-27 10:53:49.854: D/StrictMode(12541):     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
37334 09-27 10:53:49.854: D/StrictMode(12541):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

Would I be correct in assuming that this issue is due to the code that B4A generates rather than what I have written? And hence it will be fixed in a future version of B4A?

 

[DonManfred]

What code is causing the Error? Means: What does you app do? Post some code.

https://developer.android.com/reference/android/os/strictmode/NonSdkApiUsedViolation

Subclass of Violation that is used when a process accesses a non SDK API.

 

[CaptKronos]

From the logcat I have no idea what code is causing the issues. As far as I can see the enforcement of the violation has been introduced with Android 9 (API 28). I'll follow the advice presented here:

https://developer.android.com/about/versions/pie/restrictions-non-sdk-interfaces

My post was really just a heads up on what seems to be changing rather than expecting anyone to debug my code. If no one else has been impacted by the Android 9 change, then it must be something at my end.

 

[DonManfred]

How can I detect non-SDK interface uses when my app is running?

A logcat warning is printed of the form Accessing hidden field|method .... In addition, toast messages are shown for debuggable apps, and logcat messages are printed for any non-SDK interfaces that are denied.

So you´ll probably get more infos in the unfiltered log.

 

[CaptKronos]

I have been testing using the emulator running API 28 and I can't see any NonSdkApiUsedViolation syslog messages. (I'm using Android Studio's viewer.) I thought it might be because StrictMode had to be explicitly set so I used Informatix's StrictMode lib to do so. I saw the usual StrictMode "noise" but still no NonSdkApiUsedViolation messages. Is there a particular API 28 image that I need to use? The Android Developer docs seem to suggest any API 28 image should work.

 

[Erel]

It is probably not a real issue. Check the unfiltered logs when you run your app on an Android 9 device. You should see a message about the restricted access. If it is marked as "light-gray" then it is fine.

 

[CaptKronos]

Thanks. Unfortunately I don't have an Android 9 device but once I do I'll follow your suggestion. In the mean time I won't worry too much about it.

 

[Erel]

The emulator should be good for this test.

 

[CaptKronos]

In which case I am confused again since, as I said in yesterday's post, when testing with the emulator I couldn't get any NonSdkApiUsedViolation messages to appear in the syslog. However, I still won't worry about it.

 

[Erel]

Have you checked the unfiltered logs? It is easy to miss those messages.

You can see the message if you call Msgbox or DoEvents.

 

[CaptKronos]

I have created a project with just

Sub Button1_Click
    For i=0 To 10
        DoEvents
    Next
    Msgbox("hello", "title")
End Sub

and I still don't see any messages referring to NonSdkApiUsedViolation. Filter is definitely off.

 

[Erel]

I confirm. The messages only appear on the real device.

They look like:
Accessing hidden method Landroid/os/MessageQueue;->next()Landroid/os/Message; (light greylist, reflection)

 

[CaptKronos]

Thanks. I better try and borrow a real device!