microsoft / microsoft/microsoft-ui-xaml
Setting certain controls in VisualState crash the app
- Dominant language
- C++
- Stars
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Description
### Describe the bug
I am setting `ContentPresenter.Content` to some controls in a `VisualState`. It crashes the app on certain larger / more complex controls, but it's okay for basic `Button`.
It's kind of a weird and corner-case usage I know, but if it's by design it should be documented somewhere.
### Steps to reproduce the bug
1. Use this xaml
```xml
State1
State2
```
2. In code behind, you simply switch states according to the selected `ComboBox` item.
```cpp
void ComboBox_SelectionChanged(winrt::Windows::Foundation::IInspectable const& sender, winrt::Microsoft::UI::Xaml::Controls::SelectionChangedEventArgs const& e)
{
winrt::check_bool(winrt::Microsoft::UI::Xaml::VisualStateManager::GoToState(
*this,
sender.as().SelectedItem().as(),
false
));
}
```
3. Build and run. Switch the state from the comboBox the first time, it works without issue. But switch back to the same state, it crashes.
### Expected behavior
No crash.
### Screenshots

### NuGet package version
WinUI 3 - Windows App SDK 1.6.3: 1.6.241114003
### Windows version
Windows 11 (23H2): Build 22631
### Additional context
This happens to UWP and WinUI3.
[Repro](https://github.com/HO-COOH/WinUI-Bug/tree/main/23-VisualStateControlCrash)
Contributor guide
Research direction
Start with the linked 23-VisualStateControlCrash reproduction and switch repeatedly between the two VisualState values, comparing CalendarView with Button. Trace the VisualStateManager state transition and ContentPresenter content replacement; done means repeated transitions no longer crash for the reported controls, with regression coverage if an appropriate test location is found.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- desktop, frontend
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100