jonathanpeppers commented 5 years ago

R8 by default?

Context: https://developer.android.com/studio/preview/features/#R8-enabled

We are already planning to enable D8 by default in some future Xamarin.Android release.

In the current Android Studio preview, R8 is enabled by default. (not just D8!)

To turn R8 off, you can add the following to your build.gradle:

// android.enableR8 is true by default
android.enableR8 = false

Looking through the details minifyEnabled also defaults to false.

Given R8's help output:

Usage: r8 [options] <input-files>
 where <input-files> are any combination of dex, class, zip, jar, or apk files
 and options are:
  --release                # Compile without debugging information (default).
  --debug                  # Compile with debugging information.
  --output <file>          # Output result in <file>.
                           # <file> must be an existing directory or a zip file.
  --lib <file>             # Add <file> as a library resource.
  --min-api                # Minimum Android API level compatibility.
  --pg-conf <file>         # Proguard configuration <file>.
  --pg-map-output <file>   # Output the resulting name and line mapping to <file>.
  --no-tree-shaking        # Force disable tree shaking of unreachable classes.
  --no-minification        # Force disable minification of names.
  --no-desugaring          # Force disable desugaring.
  --main-dex-rules <file>  # Proguard keep rules for classes to place in the
                           # primary dex file.
  --main-dex-list <file>   # List of classes to place in the primary dex file.
  --main-dex-list-output <file>  # Output the full main-dex list in <file>.
  --version                # Print the version of r8.
  --help                   # Print this message.

We think Android Studio is running R8 by default with --no-minification.

This means:

They are using "tree shaking" by default. (Removing unreachable classes)
They are using "desugar" by default.

I suspect the --no-minification switch is used, merely because it speeds up the build and perhaps it breaks Java debugging in some way?

Investigation

To be confident in what is actually happening, we should create a Java class in Android Studio Preview that is using R8 by default. We should create an instance of the Java type and call it via Java's reflection APIs and see if that breaks.

If such Java reflection fails, then likely the "tree shaking" feature is for sure being used. C# will likely fail in the exact same way as Java refection, unfortunately.

We can test such a configuration in Xamarin.Android by doing:

<AndroidDexTool>d8</AndroidDexTool>
<AndroidLinkTool>r8</AndroidLinkTool>
<AndroidR8ExtraArguments>--no-minification</AndroidR8ExtraArguments>

NOTE: This project should have no proguard configuration files.

We will need to see what happens to a "hello world" Xamarin.Forms app using this combination.

Implementation

A big TODO here. More investigation is needed.

jonathanpeppers commented 5 years ago

/cc @JonDouglas

jonpryor commented 5 years ago

Plausible idea for this: we could add a new Linker step which would record every Java type & method that was referenced and emit a corresponding ProGuard preservation file.

This should allow the full r8/proguard Java-side linker to do as much Java-side linking as possible without breaking the apps.

EmilAlipiev commented 3 years ago

how do you do android.enableR8.fullMode=true in xamarin? https://developer.android.com/studio/build/shrink-code

jonathanpeppers commented 3 years ago

@EmilAlipiev if you need android.enableR8.fullMode, you might file a new issue as a feature request. Xamarin.Android is running r8 in the default, proguard-compatible way.

I don't see any documentation as to what the mode actually does. What flags does it pass to r8.jar?

jonmdev commented 1 month ago

I think R8 should be enabled by default but please be advised if you enable it (manually or by default), every app using WebView will currently be crashing due to this:

https://github.com/dotnet/maui/issues/23027

R8 is not currently even usable then by choice if WebView is part of the app.

jonathanpeppers commented 1 month ago

@jonmdev what is the crash? It feels like MAUI needs to add a proguard rule of their own.

Normally it says something like Java method XYZ did not exist.

jonmdev commented 1 month ago

@jonmdev what is the crash? It feels like MAUI needs to add a proguard rule of their own.

Normally it says something like Java method XYZ did not exist.

Thanks for the reply. I don't actually know what the error is. It only happens in Release mode so I have no Debugger. The Debugger in Visual Studio also disconnects when you switch away from the app and does not reconnect when you switch back (which is when the crash occurs).

So I have not seen the error, except that it crashes reliably every time as described in that bug report.

My entire bug report code is a default project with only App.xaml.cs replaced with:

namespace WebViewR8Bug {
    public partial class App : Application {
        public App() {

            ContentPage mainPage = new();
            this.MainPage = mainPage;

            AbsoluteLayout absRoot = new();
            mainPage.Content = absRoot;

            WebView webView = new();
            webView.WidthRequest = 300; 
            webView.HeightRequest = 300;
            webView.Source = "https://google.com";

            absRoot.Add(webView);
        }
    }
}

How do you suggest I capture the error code? Or can you try if there is some way you know?

The repro project is: https://github.com/jonmdev/WebViewR8Bug

Steps To Reproduce:

1) Open Developer Options in Android Phone and set Background Process Limit to 0-1 range. 2) Build Bug Project in Release to Android device with R8 Enabled. 3) Press ||| button on Android bottom tray and navigate to a few other open apps sequentially. 4) Press ||| button on Android bottom tray and navigate back to the Maui App. 5) With R8 enabled, it will then briefly show the splash icon and crash.

jonathanpeppers commented 1 month ago

adb logcat will show the error:

https://docs.microsoft.com/xamarin/android/deploy-test/debugging/android-debug-log

It should print out the full stack trace on both the Java and C# side.

jonmdev commented 1 month ago

adb logcat will show the error:
* https://docs.microsoft.com/xamarin/android/deploy-test/debugging/android-debug-log
It should print out the full stack trace on both the Java and C# side.

That did work to get the error - java.lang.NoSuchFieldException: CREATOR. Here is the critical section:

Time    Device Name Type    PID Tag Message
07-08 18:52:37.994  Samsung     Warning 1825    ActivityManager crash : com.companyname.r8crashbug,11366
  Force finishing activity com.companyname.r8crashbug/crc64ac3e9cc1ca5e515f.MainActivity
07-08 18:52:37.994  Samsung     Debug   1825    Debug   low && ship && 3rdparty app crash, do not dump
07-08 18:52:37.994  Samsung     Info    1825    DropBoxManagerService   add tag=data_app_crash isTagEnabled=true flags=0x2
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   Caused by: java.lang.NoSuchFieldException: CREATOR
    at java.lang.Class.getField(Class.java:2337)
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5004)
    ... 34 more
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   android.os.BadParcelableException: Parcelable protocol requires a Parcelable.Creator object called CREATOR on class androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5027)
    at android.os.Parcel.readParcelableInternal(Parcel.java:4873)
    at android.os.Parcel.readValue(Parcel.java:4633)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.readSparseArrayInternal(Parcel.java:5493)
    at android.os.Parcel.readValue(Parcel.java:4717)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.-$$Nest$mreadValue(Unknown Source:0)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4500)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4459)
    at android.os.BaseBundle.unwrapLazyValueFromMapLocked(BaseBundle.java:415)
    at android.os.BaseBundle.getValueAt(BaseBundle.java:401)
    at android.os.BaseBundle.getValue(BaseBundle.java:381)
    at android.os.BaseBundle.getValue(BaseBundle.java:364)
    at android.os.BaseBundle.getValue(BaseBundle.java:357)
    at android.os.Bundle.getSparseParcelableArray(Bundle.java:1108)
    at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2282)
    at android.app.Activity.onRestoreInstanceState(Activity.java:1886)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onRestoreInstanceState(Native Method)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onRestoreInstanceState(SourceFile:1)
    at android.app.Activity.performRestoreInstanceState(Activity.java:1839)
    at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1503)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4214)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:225)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2685)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:230)
    at android.os.Looper.loop(Looper.java:319)
    at android.app.ActivityThread.main(ActivityThread.java:8893)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:608)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1103)
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   
  --- End of managed Java.Lang.RuntimeException stack trace ---
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   Caused by: java.lang.NoSuchFieldException: CREATOR
    at java.lang.Class.getField(Class.java:2337)
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5004)
    ... 34 more
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   android.os.BadParcelableException: Parcelable protocol requires a Parcelable.Creator object called CREATOR on class androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5027)
    at android.os.Parcel.readParcelableInternal(Parcel.java:4873)
    at android.os.Parcel.readValue(Parcel.java:4633)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.readSparseArrayInternal(Parcel.java:5493)
    at android.os.Parcel.readValue(Parcel.java:4717)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.-$$Nest$mreadValue(Unknown Source:0)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4500)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4459)
    at android.os.BaseBundle.unwrapLazyValueFromMapLocked(BaseBundle.java:415)
    at android.os.BaseBundle.getValueAt(BaseBundle.java:401)
    at android.os.BaseBundle.getValue(BaseBundle.java:381)
    at android.os.BaseBundle.getValue(BaseBundle.java:364)
    at android.os.BaseBundle.getValue(BaseBundle.java:357)
    at android.os.Bundle.getSparseParcelableArray(Bundle.java:1108)
    at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2282)
    at android.app.Activity.onRestoreInstanceState(Activity.java:1886)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onRestoreInstanceState(Native Method)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onRestoreInstanceState(SourceFile:1)
    at android.app.Activity.performRestoreInstanceState(Activity.java:1839)
    at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1503)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4214)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:225)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2685)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:230)
    at android.os.Looper.loop(Looper.java:319)
    at android.app.ActivityThread.main(ActivityThread.java:8893)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:608)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1103)
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   
   Exception_EndOfInnerExceptionStack
   at Java.Interop.JniEnvironment.InstanceMethods.CallNonvirtualVoidMethod(JniObjectReference , JniObjectReference , JniMethodInfo , JniArgumentValue* )
   at Java.Interop.JniPeerMembers.JniInstanceMethods.InvokeVirtualVoidMethod(String , IJavaPeerable , JniArgumentValue* )
   at Android.App.Activity.OnRestoreInstanceState(Bundle )
   at Microsoft.Maui.MauiAppCompatActivity.OnRestoreInstanceState(Bundle savedInstanceState)
   at Android.App.Activity.n_OnRestoreInstanceState_Landroid_os_Bundle_(IntPtr jnienv, IntPtr native__this, IntPtr native_savedInstanceState)
   at Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPL_V(_JniMarshal_PPL_V callback, IntPtr jnienv, IntPtr klazz, IntPtr p0)
  --- End of managed Java.Lang.RuntimeException stack trace ---
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   java.lang.NoSuchFieldException: CREATOR
    at java.lang.Class.getField(Class.java:2337)
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5004)
    at android.os.Parcel.readParcelableInternal(Parcel.java:4873)
    at android.os.Parcel.readValue(Parcel.java:4633)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.readSparseArrayInternal(Parcel.java:5493)
    at android.os.Parcel.readValue(Parcel.java:4717)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.-$$Nest$mreadValue(Unknown Source:0)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4500)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4459)
    at android.os.BaseBundle.unwrapLazyValueFromMapLocked(BaseBundle.java:415)
    at android.os.BaseBundle.getValueAt(BaseBundle.java:401)
    at android.os.BaseBundle.getValue(BaseBundle.java:381)
    at android.os.BaseBundle.getValue(BaseBundle.java:364)
    at android.os.BaseBundle.getValue(BaseBundle.java:357)
    at android.os.Bundle.getSparseParcelableArray(Bundle.java:1108)
    at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2282)
    at android.app.Activity.onRestoreInstanceState(Activity.java:1886)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onRestoreInstanceState(Native Method)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onRestoreInstanceState(SourceFile:1)
    at android.app.Activity.performRestoreInstanceState(Activity.java:1839)
    at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1503)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4214)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:225)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2685)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:230)
    at android.os.Looper.loop(Looper.java:319)
    at android.app.ActivityThread.main(ActivityThread.java:8893)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:608)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1103)
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   
  --- End of managed Java.Lang.Exception stack trace ---
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   java.lang.NoSuchFieldException: CREATOR
    at java.lang.Class.getField(Class.java:2337)
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5004)
    at android.os.Parcel.readParcelableInternal(Parcel.java:4873)
    at android.os.Parcel.readValue(Parcel.java:4633)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.readSparseArrayInternal(Parcel.java:5493)
    at android.os.Parcel.readValue(Parcel.java:4717)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.-$$Nest$mreadValue(Unknown Source:0)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4500)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4459)
    at android.os.BaseBundle.unwrapLazyValueFromMapLocked(BaseBundle.java:415)
    at android.os.BaseBundle.getValueAt(BaseBundle.java:401)
    at android.os.BaseBundle.getValue(BaseBundle.java:381)
    at android.os.BaseBundle.getValue(BaseBundle.java:364)
    at android.os.BaseBundle.getValue(BaseBundle.java:357)
    at android.os.Bundle.getSparseParcelableArray(Bundle.java:1108)
    at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2282)
    at android.app.Activity.onRestoreInstanceState(Activity.java:1886)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onRestoreInstanceState(Native Method)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onRestoreInstanceState(SourceFile:1)
    at android.app.Activity.performRestoreInstanceState(Activity.java:1839)
    at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1503)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4214)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:225)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2685)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:230)
    at android.os.Looper.loop(Looper.java:319)
    at android.app.ActivityThread.main(ActivityThread.java:8893)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:608)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1103)
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   
  --- End of managed Java.Lang.Exception stack trace ---
07-08 18:52:37.992  Samsung     Info    14352   MonoDroid   Java.Lang.RuntimeException: Parcelable protocol requires a Parcelable.Creator object called CREATOR on class androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState
 ---> Java.Lang.Exception: CREATOR
07-08 18:52:37.985  Samsung     Info    14352   MonoDroid   UNHANDLED EXCEPTION:
07-08 18:52:37.984  Samsung     Warning 14352   monodroid-assembly  Shared library 'liblog' not loaded, p/invoke '__android_log_print' may fail
07-08 18:52:37.980  Samsung     Error   14352   AndroidRuntime  Caused by: java.lang.NoSuchFieldException: CREATOR
    at java.lang.Class.getField(Class.java:2337)
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5004)
    ... 34 more
07-08 18:52:37.980  Samsung     Error   14352   AndroidRuntime  android.os.BadParcelableException: Parcelable protocol requires a Parcelable.Creator object called CREATOR on class androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState
    at android.os.Parcel.readParcelableCreatorInternal(Parcel.java:5027)
    at android.os.Parcel.readParcelableInternal(Parcel.java:4873)
    at android.os.Parcel.readValue(Parcel.java:4633)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.readSparseArrayInternal(Parcel.java:5493)
    at android.os.Parcel.readValue(Parcel.java:4717)
    at android.os.Parcel.readValue(Parcel.java:4402)
    at android.os.Parcel.-$$Nest$mreadValue(Unknown Source:0)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4500)
    at android.os.Parcel$LazyValue.apply(Parcel.java:4459)
    at android.os.BaseBundle.unwrapLazyValueFromMapLocked(BaseBundle.java:415)
    at android.os.BaseBundle.getValueAt(BaseBundle.java:401)
    at android.os.BaseBundle.getValue(BaseBundle.java:381)
    at android.os.BaseBundle.getValue(BaseBundle.java:364)
    at android.os.BaseBundle.getValue(BaseBundle.java:357)
    at android.os.Bundle.getSparseParcelableArray(Bundle.java:1108)
    at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2282)
    at android.app.Activity.onRestoreInstanceState(Activity.java:1886)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onRestoreInstanceState(Native Method)
    at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onRestoreInstanceState(SourceFile:1)
    at android.app.Activity.performRestoreInstanceState(Activity.java:1839)
    at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1503)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:4214)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:225)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2685)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:230)
    at android.os.Looper.loop(Looper.java:319)
    at android.app.ActivityThread.main(ActivityThread.java:8893)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:608)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1103)
07-08 18:52:37.980  Samsung     Error   14352   AndroidRuntime  Process: com.companyname.r8crashbug, PID: 14352
07-08 18:52:37.980  Samsung     Error   14352   AndroidRuntime  FATAL EXCEPTION: main
07-08 18:52:37.980  Samsung     Debug   14352   AndroidRuntime  Shutting down VM

Any thoughts or solutions? Thanks.

jonathanpeppers commented 1 month ago

So, the error is related to androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState missing a CREATOR field, reading this post:

https://stackoverflow.com/a/55705308

I think you could make a Platforms/Android/proguard.txt file that contains the contents:

-keepnames class * implements android.os.Parcelable {
    public static final ** CREATOR;
}

It should preserve static CREATOR fields on all Parcelable implementations.

jonmdev commented 1 month ago

So, the error is related to androidx.coordinatorlayout.widget.CoordinatorLayout$SavedState missing a CREATOR field, reading this post:
* https://stackoverflow.com/a/55705308
I think you could make a Platforms/Android/proguard.txt file that contains the contents:
-keepnames class * implements android.os.Parcelable {
    public static final ** CREATOR;
}
It should preserve static CREATOR fields on all Parcelable implementations.

That worked!

I added a Platforms/Android/proguard.cfg file that says:

-keepnames class * implements android.os.Parcelable {
    public static final ** CREATOR;
}

I had to mark the file properties as ProGuardConfiguration as shown here: https://learn.microsoft.com/en-us/previous-versions/xamarin/android/deploy-test/release-prep/proguard?tabs=windows

I also found this similar thread where you discussed similar issues: https://github.com/dotnet/maui/issues/13413

Thanks for the solution. I think that will need to be added as a Maui fix. I will update the bug report thread on this one.

jonathanpeppers commented 1 month ago

Can you commit your changes to:

https://github.com/jonmdev/WebViewR8Bug

It seems like this default wildcard should work without update the project file, but then I realized MAUI has a copy:

https://github.com/dotnet/maui/blob/fe224da90bccc3c1926c1c547c780aec409b2315/src/Controls/src/Build.Tasks/nuget/buildTransitive/netstandard2.0/Microsoft.Maui.Controls.Globs.props#L43-L55

jonmdev commented 1 month ago

Can you commit your changes to:
* https://github.com/jonmdev/WebViewR8Bug

Sure, done.

dotnet / android

[spec] should Xamarin.Android enable R8 by default? #2804

R8 by default?

Investigation

Implementation