public Theme?GetTheme(ResourceDictionary resourceDictionary)
{
if (resourceDictionary is null)
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
var themeInstance = Theme.GetThemeInstance(resourceDictionary);
if (themeInstance is not null)
{
return(themeInstance);
}
var builtInTheme = this.Themes.FirstOrDefault(x => x.Name == Theme.GetThemeName(resourceDictionary));
if (builtInTheme is not null)
{
return(builtInTheme);
}
// support dynamically created runtime resource dictionaries
if (this.IsRuntimeGeneratedThemeDictionary(resourceDictionary))
{
foreach (var resourceDictionaryKey in resourceDictionary.Keys)
{
if (Theme.ThemeInstanceKey.Equals(resourceDictionaryKey))
{
return((Theme)resourceDictionary[resourceDictionaryKey]);
}
}
foreach (var resourceDictionaryKey in resourceDictionary.Keys)
{
if (LibraryTheme.LibraryThemeInstanceKey.Equals(resourceDictionaryKey))
{
var parentTheme = ((LibraryTheme)resourceDictionary[resourceDictionaryKey]).ParentTheme;
if (parentTheme is not null)
{
return(parentTheme);
}
}
}
return(new Theme(new LibraryTheme(resourceDictionary, null)));
}
return(null);
}
private Theme ChangeTheme(object?target, ResourceDictionary resourceDictionary, Theme?oldTheme, Theme newTheme)
{
if (resourceDictionary is null)
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
if (newTheme is null)
{
throw new ArgumentNullException(nameof(newTheme));
}
var themeChanged = false;
if (oldTheme != newTheme)
{
resourceDictionary.BeginInit();
try
{
ResourceDictionary? oldThemeDictionary = null;
List <ResourceDictionary>?oldThemeResources = null;
if (oldTheme is not null)
{
oldThemeDictionary = resourceDictionary.MergedDictionaries.FirstOrDefault(d => Theme.GetThemeInstance(d) == oldTheme);
if (oldThemeDictionary is null)
{
oldThemeResources = resourceDictionary.MergedDictionaries.Where(d => Theme.GetThemeName(d) == oldTheme.Name)
.ToList();
}
}
{
newTheme.EnsureAllLibraryThemeProvidersProvided();
resourceDictionary.MergedDictionaries.Add(newTheme.Resources);
//foreach (var themeResource in newTheme.GetAllResources())
//{
// // todo: Should we really append the theme resources or try to insert them at a specific index?
// // The problem here would be to get the correct index.
// // Inserting them at index 0 is not a good idea as user included resources, like generic.xaml, would be behind our resources.
// //resourceDictionary.MergedDictionaries.Insert(0, themeResource);
// resourceDictionary.MergedDictionaries.Add(themeResource);
//}
}
if (oldThemeDictionary is not null)
{
resourceDictionary.MergedDictionaries.Remove(oldThemeDictionary);
}
else if (oldThemeResources is not null)
{
foreach (var themeResource in oldThemeResources)
{
resourceDictionary.MergedDictionaries.Remove(themeResource);
}
}
themeChanged = true;
}
finally
{
resourceDictionary.EndInit();
}
}
if (themeChanged)
{
this.OnThemeChanged(target, resourceDictionary, oldTheme, newTheme);
}
return(newTheme);
}