[UWP] How to set ThemeResource in C# RRS feed

  • Question

  • Hi! I make UWP app and I want to set ThemeResource in C#:


            <ResourceDictionary x:Key="Light">
                <SolidColorBrush x:Key="MessageBubbleBackground" Color="#bdc3c7"/>
                <SolidColorBrush x:Key="MessageBubbleForeground" Color="Black"/>
                <SolidColorBrush x:Key="MyMessageBubbleBackground" Color="#3498db"/>
                <SolidColorBrush x:Key="MyMessageBubbleForeground" Color="White"/>
            <ResourceDictionary x:Key="Dark">
                <SolidColorBrush x:Key="MessageBubbleBackground" Color="#34495e"/>
                <SolidColorBrush x:Key="MessageBubbleForeground" Color="White"/>
                <SolidColorBrush x:Key="MyMessageBubbleBackground" Color="#27ae60"/>
                <SolidColorBrush x:Key="MyMessageBubbleForeground" Color="White"/>


    <Grid x:Name="bubbleBody" Background="{ThemeResource MessageBubbleBackground}">
        <RichTextBlock Margin="10" MaxWidth="300">
               <Run x:Name="bubbleText"/>


    private static ResourceDictionary _bubblesThemes = new ResourceDictionary()
        Source = new System.Uri("ms-appx:///MessageBubbleThemes.xaml")
    bubbleBody.Background = (SolidColorBrush)_bubblesThemes["MyMessageBubbleBackground"];
    bubbleText.Foreground = (SolidColorBrush)_bubblesThemes["MyMessageBubbleForeground"];

    If I set Background as ThemeResource in XAML, then MessageBubble change his background on theme changed in Settings app, but if I set Background in C#, then MessageBubble don't change his background on theme changed.

    How can I solve it?

    Saturday, August 1, 2020 7:56 AM

All replies

  • Hi Puelt,

    Since this thread is related to UWP, so I suggest that you can ask this question in Microsoft Q&A.

    The Visual C# forum discusses and asks questions about the C# programming language, IDE, libraries, samples, and tools.

    Best Regards,


    MSDN Community Support
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    Monday, August 3, 2020 2:52 AM