Mahapps.metro: High contrast detection in Theme Manager

Created on 2 Jun 2020 · 3Comments · Source: MahApps/MahApps.Metro

I am working on a WPF project that involves changing theme dynamically at runtime based on Light/Dark/High Contrast mode and I am trying to use ThemeManager for it.

I have added four custom themes Light.Accent1, Dark.Accent1, HC.Light.Accent1 and HC.Dark.Accent1 as given below :

Light.Accent1

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:markup="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:markupWithAssembly="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                    xmlns:options="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" xmlns:system="clr-namespace:System;assembly=System.Runtime"
                    mc:Ignorable="options">

    <!--  Metadata  -->
    <system:String x:Key="Theme.Name">Light.Accent1</system:String>
    <system:String x:Key="Theme.Origin">MahAppsMetroThemesSample</system:String>
    <system:String x:Key="Theme.DisplayName">Accent1 (Light)</system:String>
    <system:String x:Key="Theme.BaseColorScheme">Light</system:String>
    <system:String x:Key="Theme.ColorScheme">Accent1</system:String>
    <Color x:Key="Theme.PrimaryAccentColor">Red</Color>
    <SolidColorBrush x:Key="SystemChromeLow" Color="Green" options:Freeze="True" />
</ResourceDictionary>

Dark.Accent1

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:markup="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:markupWithAssembly="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                    xmlns:options="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" xmlns:system="clr-namespace:System;assembly=System.Runtime"
                    mc:Ignorable="options">

    <!--  Metadata  -->
    <system:String x:Key="Theme.Name">Dark.Accent1</system:String>
    <system:String x:Key="Theme.Origin">MahAppsMetroThemesSample</system:String>
    <system:String x:Key="Theme.DisplayName">Accent1 (Dark)</system:String>
    <system:String x:Key="Theme.BaseColorScheme">Dark</system:String>
    <system:String x:Key="Theme.ColorScheme">Accent1</system:String>
    <Color x:Key="Theme.PrimaryAccentColor">Red</Color>
    <SolidColorBrush x:Key="SystemChromeLow" Color="Red" options:Freeze="True" />
</ResourceDictionary>

HC.Light.Accent1

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:markup="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:markupWithAssembly="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                    xmlns:options="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" xmlns:system="clr-namespace:System;assembly=System.Runtime"
                    mc:Ignorable="options">

    <!--  Metadata  -->
    <system:String x:Key="Theme.Name">Light.Accent1</system:String>
    <system:String x:Key="Theme.Origin">MahAppsMetroThemesSample</system:String>
    <system:String x:Key="Theme.DisplayName">Accent1 (Light)</system:String>
    <system:String x:Key="Theme.BaseColorScheme">Light</system:String>
    <system:String x:Key="Theme.ColorScheme">Accent1</system:String>
    <Color x:Key="Theme.PrimaryAccentColor">Red</Color>
    <system:Boolean x:Key="Theme.IsHighContrast">true</system:Boolean>
    <SolidColorBrush x:Key="SystemChromeLow" Color="Blue" options:Freeze="True" />
</ResourceDictionary>

HC.Dark.Accent1

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:markup="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:markupWithAssembly="clr-namespace:MahApps.Metro.Markup;assembly=MahApps.Metro"
                    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                    xmlns:options="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" xmlns:system="clr-namespace:System;assembly=System.Runtime"
                    mc:Ignorable="options">

    <!--  Metadata  -->
    <system:String x:Key="Theme.Name">Dark.Accent1</system:String>
    <system:String x:Key="Theme.Origin">MahAppsMetroThemesSample</system:String>
    <system:String x:Key="Theme.DisplayName">Accent1 (Dark)</system:String>
    <system:String x:Key="Theme.BaseColorScheme">Dark</system:String>
    <system:String x:Key="Theme.ColorScheme">Accent1</system:String>
    <system:Boolean x:Key="Theme.IsHighContrast">true</system:Boolean>
    <Color x:Key="Theme.PrimaryAccentColor">Red</Color>
    <SolidColorBrush x:Key="SystemChromeLow" Color="Yellow" options:Freeze="True" />
</ResourceDictionary>

Code to auto sync theme with current system colors :

ThemeManager.Current.AddLibraryTheme(new LibraryTheme(
                                                         new Uri("pack://application:,,,/Light.Accent1.xaml"),
                                                         MahAppsLibraryThemeProvider.DefaultInstance));
ThemeManager.Current.AddLibraryTheme(new LibraryTheme(
                                                        new Uri("pack://application:,,,/Dark.Accent1.xaml"),
                                                        MahAppsLibraryThemeProvider.DefaultInstance));
ThemeManager.Current.AddLibraryTheme(new LibraryTheme(
                                                        new Uri("pack://application:,,,/HC.Dark.Accent1.xaml"),
                                                        MahAppsLibraryThemeProvider.DefaultInstance));
ThemeManager.Current.AddLibraryTheme(new LibraryTheme(
                                                        new Uri("pack://application:,,,/HC.Light.Accent1.xaml"),
                                                        MahAppsLibraryThemeProvider.DefaultInstance));
ThemeManager.Current.ChangeTheme(this, "Light.Accent1");
ThemeManager.Current.ThemeSyncMode = ThemeSyncMode.SyncWithAppMode;
ThemeManager.Current.SyncTheme(ThemeSyncMode.SyncWithAppMode);

The detection works fine in automatically syncing themes when system colors change from Light to Dark mode and vice versa. But turning on High contrast mode doesn't change to corresponding theme i.e HC.Light.Accent1 and HC.Dark.Accent1

Is there something I am missing?

Bug

Source