public static bool IsThemeDictionary(ResourceDictionary resourceDictionary)
{
if (resourceDictionary is null)
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
var source = resourceDictionary.Source;
if (!(source is null))
{
if (ThemeDictionaryCache.TryGetValue(source, out var existingValue))
{
return(existingValue);
}
}
// We are not allowed to use other methods like GetThemeInstance or GetThemeName here as that would cause an endless-loop
var result = ResourceDictionaryHelper.ContainsKey(resourceDictionary, ThemeInstanceKey) ||
string.IsNullOrEmpty(ResourceDictionaryHelper.GetValueFromKey(resourceDictionary, ThemeNameKey) as string) == false;
if (!(source is null))
{
ThemeDictionaryCache[source] = result;
}
return(result);
}
public static Theme?GetThemeInstance([NotNull] ResourceDictionary resourceDictionary)
{
if (resourceDictionary is null)
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
if (IsThemeDictionary(resourceDictionary) == false)
{
return(null);
}
return(ResourceDictionaryHelper.GetValueFromKey(resourceDictionary, ThemeInstanceKey) as Theme);
}
public static string?GetThemeName(ResourceDictionary resourceDictionary)
{
if (resourceDictionary is null)
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
if (IsThemeDictionary(resourceDictionary) == false)
{
return(null);
}
return(ResourceDictionaryHelper.GetValueFromKey(resourceDictionary, ThemeNameKey) as string);
}