[regression/8.0.0-preview.3.8149] Crash when using NavigationPage.TitleView (Java.Lang.IllegalStateException: The specified child already has a parent)

[tranb3r]

Description

When using NavigationPage.TitleView, an app crashes when being launched again after it has been killed by the system.
Here is the exception: Java.Lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.

Steps to Reproduce

1. in android settings, developer options, enable "don't keep activites"
2. launch test app, then tap on home button: app goes to background, and is killed by system
3. launch app again, it crashes

Link to public reproduction project repository

Repro

Version with bug

8.0.0-preview.3.8149

Last version that worked well

8.0.0-preview.2.7871

Affected platforms

Android

Affected platform versions

No response

Did you find any workaround?

No

Relevant log output

Java.Lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
   at Java.Interop.JniEnvironment.InstanceMethods.CallVoidMethod(JniObjectReference , JniMethodInfo , JniArgumentValue* )
   at Java.Interop.JniPeerMembers.JniInstanceMethods.InvokeVirtualVoidMethod(String , IJavaPeerable , JniArgumentValue* )
   at Android.Views.ViewGroup.AddView(View )
   at Microsoft.Maui.Controls.Toolbar.UpdateTitleView()
   at Microsoft.Maui.Controls.Toolbar.MapTitleView(IToolbarHandler , Toolbar )
   at Microsoft.Maui.Controls.Toolbar.MapTitleView(ToolbarHandler arg1, Toolbar arg2)
   at Microsoft.Maui.PropertyMapper`2.<>c__DisplayClass5_0[[Microsoft.Maui.Controls.Toolbar, Microsoft.Maui.Controls, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Handlers.ToolbarHandler, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].<Add>b__0(IElementHandler h, IElement v)
   at Microsoft.Maui.PropertyMapper.UpdatePropertyCore(String , IElementHandler , IElement )
   at Microsoft.Maui.PropertyMapper.UpdateProperties(IElementHandler , IElement )
   at Microsoft.Maui.Handlers.ElementHandler.SetVirtualView(IElement )
   at Microsoft.Maui.Platform.ElementExtensions.ToHandler(IElement , IMauiContext )
   at Microsoft.Maui.Platform.ElementExtensions.ToPlatform(IElement , IMauiContext )
   at Microsoft.Maui.Handlers.ViewHandler.MapToolbar(IElementHandler , IToolbarElement )
   at Microsoft.Maui.Handlers.WindowHandler.MapToolbar(IWindowHandler handler, IWindow view)
   at Microsoft.Maui.PropertyMapper`2.<>c__DisplayClass5_0[[Microsoft.Maui.IWindow, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Handlers.IWindowHandler, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].<Add>b__0(IElementHandler h, IElement v)
   at Microsoft.Maui.PropertyMapper.UpdatePropertyCore(String , IElementHandler , IElement )
   at Microsoft.Maui.PropertyMapper.UpdateProperties(IElementHandler , IElement )
   at Microsoft.Maui.Handlers.ElementHandler.SetVirtualView(IElement )
   at Microsoft.Maui.Controls.Element.SetHandler(IElementHandler )
   at Microsoft.Maui.Controls.Element.set_Handler(IElementHandler value)
   at Microsoft.Maui.Platform.ElementExtensions.SetHandler(Context , IElement , IMauiContext )
   at Microsoft.Maui.Platform.ElementExtensions.SetWindowHandler(Activity , IWindow , IMauiContext )
   at Microsoft.Maui.Platform.ApplicationExtensions.CreatePlatformWindow(Activity , IApplication , Bundle )
   at Microsoft.Maui.MauiAppCompatActivity.OnCreate(Bundle )
   at Android.App.Activity.n_OnCreate_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.IllegalStateException stack trace ---

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.xxx.app/crc64d002a6d246c183e1.mm}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3644)
	at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3781)
	at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101)
	at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:138)
	at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
	at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2306)
	at android.os.Handler.dispatchMessage(Handler.java:106)
	at android.os.Looper.loopOnce(Looper.java:201)
	at android.os.Looper.loop(Looper.java:288)
	at android.app.ActivityThread.main(ActivityThread.java:7918)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Caused by java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
       at android.view.ViewGroup.addViewInner(ViewGroup.java:5248)
       at android.view.ViewGroup.addView(ViewGroup.java:5077)
       at android.view.ViewGroup.addView(ViewGroup.java:5017)
       at android.view.ViewGroup.addView(ViewGroup.java:4989)
       at crc6488302ad6e9e4df1a.MauiAppCompatActivity.n_onCreate(MauiAppCompatActivity.java)
       at crc6488302ad6e9e4df1a.MauiAppCompatActivity.onCreate(MauiAppCompatActivity.java:48)
       at android.app.Activity.performCreate(Activity.java:8342)
       at android.app.Activity.performCreate(Activity.java:8321)
       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1417)
       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3625)
       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3781)
       at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101)
       at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:138)
       at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2306)
       at android.os.Handler.dispatchMessage(Handler.java:106)
       at android.os.Looper.loopOnce(Looper.java:201)
       at android.os.Looper.loop(Looper.java:288)
       at android.app.ActivityThread.main(ActivityThread.java:7918)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

[ghost]

Hi @tranb3r. We have added the "s/needs-repro" label to this issue, which indicates that we require steps and sample code to reproduce the issue before we can take further action. Please try to create a minimal sample project/solution or code samples which reproduce the issue, ideally as a GitHub repo that we can clone. See more details about creating repros here: https://github.com/dotnet/maui/blob/main/.github/repro.md

This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[ghost]

Hi @tranb3r. We have added the "s/try-latest-version" label to this issue, which indicates that we'd like you to try and reproduce this issue on the latest available public version. This can happen because we think that this issue was fixed in a version that has just been released, or the information provided by you indicates that you might be working with an older version.

You can install the latest version by installing the latest Visual Studio (Preview) with the .NET MAUI workload installed. If the issue still persists, please let us know with any additional details and ideally a reproduction project provided through a GitHub repository.

This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[tranb3r]

Here is a repro: https://github.com/tranb3r/Issues/tree/main/MauiAppDontKeepActivities

Steps to reproduce:

• in android settings, developer options, enable "don't keep activites"
• launch test app, then tap on home button: app goes to background, and is killed by system
• launch app again, it crashes

This is happening when the MainPage sets the NavigationPage.TitleView.

This is a regression in net8.
Same behavior in net8-pre5 and net8-pre6.
No crash with net7.

[jsuarezruiz]

Cannot reproduce the issue with preview 7 or in the current net8 development branch. Maybe I am missing something?

[ghost]

Hi @tranb3r. We have added the "s/needs-info" label to this issue, which indicates that we have an open question for you before we can take further action. This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[tranb3r]

I've just tested my sample app with net8-pre7 and I can still reproduce the issue.
@jsuarezruiz Are you running my sample app?
In your screen capture, it seems like the app title and splashscreen are different. Maybe some other difference could explain the exception?

[samhouts]

Confirmed that this was a regression between 8.0.0-preview.2.7871...8.0.0-preview.3.8149.

Not sure which PR is the culprit. #13879 is the most sus to me.

[samhouts]

Also, still repros in pre7.

[tranb3r]

Any update? Thanks

[tranb3r]

Still happening in RC1.