ScrollViewerAssist: Avoid TargetInvocationException on WinForms application shutdown#4015
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ScrollViewerAssist: Avoid TargetInvocationException on WinForms application shutdown#4015
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In a use case where a TabControl is hosted in an ElementHost inside of a WinForms application, the handlers were not removed, and thus an exception was thrown during application shutdown.
nicolaihenriksen
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Keboo
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Reviewed on stream if you are interested. Lgtm.
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Fixes #3439
I have pushed a branch called
reproduceIssue3439which has a WinForms demo application showcasing the issue and the fix. The last commit on the branch, is the same commit (content) as the fix in this PR. Simply revert that if you want to see the error occurring on application shutdown.In a use case where a
TabControlis hosted in anElementHostinside of a WinForms application, the handlers were not removed, and thus an exception was thrown during application shutdown.This PR registers a
HwndSourceHookwhich acts on the WM_DESTROY and WM_NCDESTROY messages in order to clean up the handlers (and unregister the hook to avoid memory leaks)