Change theme at runtime

Question

I have a WPF application with a theme (ShinyRed.xaml) and I want to have a button that when clicked changes the theme to ShinyBlue.xaml

I load in the theme initially in App.xaml:

<Application.Resources>     <ResourceDictionary Source="/Themes/ShinyBlue.xaml"/> </Application.Resources> 

How might I do this?

Answer 1

How you could do it:

<Application.Resources>     <ResourceDictionary>         <ResourceDictionary.MergedDictionaries>             <ResourceDictionary x:Name="ThemeDictionary">                 <ResourceDictionary.MergedDictionaries>                     <ResourceDictionary Source="/Themes/ShinyRed.xaml"/>                 </ResourceDictionary.MergedDictionaries>             </ResourceDictionary>         </ResourceDictionary.MergedDictionaries>     <!-- ... --> 

public partial class App : Application {     public ResourceDictionary ThemeDictionary     {         // You could probably get it via its name with some query logic as well.         get { return Resources.MergedDictionaries[0]; }     }      public void ChangeTheme(Uri uri)     {         ThemeDictionary.MergedDictionaries.Clear();         ThemeDictionary.MergedDictionaries.Add(new ResourceDictionary() { Source = uri });     }      //... } 

In your change method:

var app = (App)Application.Current; app.ChangeTheme(new Uri("New Uri here"));