private static void ApplyThemeResourceDictionary <T>(ResourceDictionary resources, Theme theme, T themeResourceDictionary) where T : ThemeResourceDictionary, new()
{
if (theme == null)
{
return;
}
if (themeResourceDictionary?.Theme != theme)
{
themeResourceDictionary = new T {
Source = theme.Source, Theme = theme
}
}
;
resources.MergedDictionaries.Add(themeResourceDictionary);
}
}
private static void ApplyTheme(object sender, ResourceDictionary resources, Theme baseTheme, Theme colorTheme)
{
Debug.Assert(resources != null);
if (WindowsHelper.IsInDesignMode)
{
// Don't do anything at design-time. (Could mess up Expression Blend.)
return;
}
// Clear previous theme.
var baseThemeResourceDictionary = ClearThemeResourceDictionary <BaseThemeResourceDictionary>(resources);
var colorThemeResourceDictionary = ClearThemeResourceDictionary <ColorThemeResourceDictionary>(resources);
// Apply new Theme.
ApplyThemeResourceDictionary(resources, baseTheme, baseThemeResourceDictionary);
ApplyThemeResourceDictionary(resources, colorTheme, colorThemeResourceDictionary);
// Raise ThemeChanged event.
var oldBaseTheme = baseThemeResourceDictionary?.Theme;
var oldColorTheme = colorThemeResourceDictionary?.Theme;
var eventArgs = new ThemeChangedEventArgs(oldBaseTheme, oldColorTheme, baseTheme, colorTheme);
ThemeChangedEvent.Invoke(sender, eventArgs);
}