Theme switching doesn't work properly

[JellyBelly1809]

Describe the bug

Hello, I am trying to implement a dark theme into my application, but trying to switch themes causes some weird behavior (see clip).

Page.cs:

private async void OnLightThemeRadioButtonChecked(object sender, RoutedEventArgs e)
{
    Wpf.Ui.Appearance.ApplicationThemeManager.Apply(Wpf.Ui.Appearance.ApplicationTheme.Light);
}

private async void OnDarkThemeRadioButtonChecked(object sender, RoutedEventArgs e)
{
    Wpf.Ui.Appearance.ApplicationThemeManager.Apply(Wpf.Ui.Appearance.ApplicationTheme.Dark);
}

MainWindow.cs:

public MainWindow()
{
    Wpf.Ui.Appearance.SystemThemeWatcher.Watch(this);
    InitializeComponent();
}

To Reproduce

Switch themes with Wpf.Ui.Appearance.ApplicationThemeManager.Apply()

Expected behavior

I would expect the themes to simply switch like in the demo app.

Screenshots

clip.mp4

OS version

Windows 11 23H2 (Build 22631.3958)

.NET version

.Net 8.0

WPF-UI NuGet version

3.0.5

Additional context

No response

[Koichi-Kobayashi]

@JellyBelly1809
I'm not sure about other versions,
but in Ver. 4.1.0, the theme is applied to the entire screen.

[ibrahimatas]

Describe the bug

Hello, I am trying to implement a dark theme into my application, but trying to switch themes causes some weird behavior (see clip).

Page.cs:

private async void OnLightThemeRadioButtonChecked(object sender, RoutedEventArgs e)
{
    Wpf.Ui.Appearance.ApplicationThemeManager.Apply(Wpf.Ui.Appearance.ApplicationTheme.Light);
}

private async void OnDarkThemeRadioButtonChecked(object sender, RoutedEventArgs e)
{
    Wpf.Ui.Appearance.ApplicationThemeManager.Apply(Wpf.Ui.Appearance.ApplicationTheme.Dark);
}

MainWindow.cs:

public MainWindow()
{
    Wpf.Ui.Appearance.SystemThemeWatcher.Watch(this);
    InitializeComponent();
}

To Reproduce

Switch themes with Wpf.Ui.Appearance.ApplicationThemeManager.Apply()

Expected behavior

I would expect the themes to simply switch like in the demo app.

Screenshots

clip.mp4

OS version

Windows 11 23H2 (Build 22631.3958)

.NET version

.Net 8.0

WPF-UI NuGet version

3.0.5

Additional context

No response

“The code below works without errors; you might want to try it.”

private void btnTheme_Click(object sender, RoutedEventArgs e)
{
var theme = ApplicationThemeManager.GetAppTheme();

if (theme == ApplicationTheme.Dark)
{
   ApplicationThemeManager.Apply(ApplicationTheme.Light);

    
    var resource = Application.Current.Resources["ApplicationBackgroundBrush"] as Brush;
    if (resource != null)
    {
        this.Background = resource;
    }
}
else
{
    ApplicationThemeManager.Apply(ApplicationTheme.Dark);

    
    var resource = Application.Current.Resources["ApplicationBackgroundBrush"] as Brush;
    if (resource != null)
    {
        this.Background = resource;
    }
}

}