Skip to content

fix: Prevent unexpected ContentDialog behavior at design time. #1543

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
pomianowski merged 2 commits into from
Nov 7, 2025
Merged

fix: Prevent unexpected ContentDialog behavior at design time. #1543

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
d814575
Prevent unexpected ContentDialog behavior at design time.
apachezy Oct 9, 2025
b07b942
Merge branch 'main' into fix/ContentDialog-design-time
pomianowski Nov 7, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
33 changes: 25 additions & 8 deletions src/Wpf.Ui/Controls/ContentDialog/ContentDialog.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -470,11 +470,16 @@ public ContentDialog()
{
SetValue(TemplateButtonCommandProperty, new RelayCommand<ContentDialogButton>(OnButtonClick));

Loaded += static (sender, _) =>
// Avoid registering runtime code that triggers designer behavior or throws exceptions
// at design time (to reduce the possibility of designer crashes/rendering failures).
if (!Wpf.Ui.Designer.DesignerHelper.IsInDesignMode)
{
var self = (ContentDialog)sender;
self.OnLoaded();
};
Loaded += static (sender, _) =>
{
var self = (ContentDialog)sender;
self.OnLoaded();
};
}
}

/// <summary>
Expand All @@ -492,11 +497,16 @@ public ContentDialog(ContentPresenter? dialogHost)

SetValue(TemplateButtonCommandProperty, new RelayCommand<ContentDialogButton>(OnButtonClick));

Loaded += static (sender, _) =>
// Avoid registering runtime code that triggers designer behavior or throws exceptions
// at design time (to reduce the possibility of designer crashes/rendering failures).
if (!Wpf.Ui.Designer.DesignerHelper.IsInDesignMode)
{
var self = (ContentDialog)sender;
self.OnLoaded();
};
Loaded += static (sender, _) =>
{
var self = (ContentDialog)sender;
self.OnLoaded();
};
}
}

/// <summary>
Expand Down Expand Up @@ -601,6 +611,12 @@ protected virtual void OnButtonClick(ContentDialogButton button)

protected override Size MeasureOverride(Size availableSize)
{
// Avoid throwing exceptions when visual child elements cannot be obtained (designer or template not applied).
if (VisualChildrenCount == 0)
{
return base.MeasureOverride(availableSize);
}

var rootElement = (UIElement)GetVisualChild(0)!;

rootElement.Measure(availableSize);
Expand All @@ -622,6 +638,7 @@ protected override Size MeasureOverride(Size availableSize)
/// </summary>
protected virtual void OnLoaded()
{
// Focus is only needed at runtime.
_ = Focus();

RaiseEvent(new RoutedEventArgs(OpenedEvent));
Expand Down
Loading