[Bug]: Putting RoutedViewHost inside a TabControl on Avalonia causes an app crash after navigating the second time

[kyurkchyan]

[Bug]: Putting RoutedViewHost inside a TabControl on Avalonia causes an app crash after navigating the second time

[kyurkchyan]

We've resolved this issue by copying the RoutedViewHost source code and adding the following inside the WhenActivated block

this.WhenActivated(disposables =>
            {
                ....

                Disposable.Create(() =>
                          {
                              Content = null;
                          })
                          .DisposeWith(disposables);
            });

This resolves the root cause of the issue. The problem is that once the view is reactivated, the same content is recreated through view location. However, that view is already attached to the parent. This means whenever the routed view host deactivates, we also need to clear its content. Otherwise, we are risking double-attaching the same view and causing this exception.

[glennawatson]

Probably worth raising this up with the Avalonia team. See if you can get the fix in.

[kyurkchyan]

@glennawatson you are actually right. I've extended the sample I've attached to this bug report. And instead of using RoutedViewHost when using bare TransitioningContentControl through assigning the Content property the same issue occurs. I will raise this Avalonia.

[kyurkchyan]

Closing this issue for the time being, for 2 reasons

1. There's a workaround
2. Most probably this should be fixed inside the TransitioningContentControl and not the RoutedViewHost. For that, an issue is opened inside the Avalonia repo

[glennawatson]

Worth noting that AvaloniaUI own both the RoutedViewHost and the TransitioningContentControl

https://github.com/AvaloniaUI/Avalonia/blob/master/src/Avalonia.ReactiveUI/RoutedViewHost.cs

So bugs with that system aren't necessarily related directly with ReactiveUI.

[kyurkchyan]

@glennawatson thanks for the info, I actually didn't realize that. And the good news is the issue is already fixed in the latest CI beta release.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.