/// <summary>
/// Gets the <see cref="Theme"/> with the given resource dictionary.
/// </summary>
/// <param name="resources"><see cref="ResourceDictionary"/> from which the theme should be retrieved.</param>
/// <returns>The <see cref="Theme"/> or <c>null</c>, if the theme wasn't found.</returns>
public static Theme GetTheme([NotNull] ResourceDictionary resources)
{
if (resources.IsNull())
{
throw new ArgumentNullException(nameof(resources));
}
var builtInTheme = Themes.FirstOrDefault(x => AreResourceDictionarySourcesEqual(x.Resources, resources));
if (builtInTheme.IsNotNull())
{
return(builtInTheme);
}
// support dynamically created runtime resource dictionaries
if (resources.Source.IsNull())
{
if (IsThemeDictionary(resources))
{
return(new Theme(resources));
}
}
return(null);
}
private static bool AreResourceDictionarySourcesEqual(ResourceDictionary first, ResourceDictionary second)
{
if (first.IsNull() ||
second.IsNull())
{
return(false);
}
if (first.Source.IsNull() ||
second.Source.IsNull())
{
try
{
foreach (var key in first.Keys)
{
var isTheSame = second.Contains(key) &&
Equals(first[key], second[key]);
if (!isTheSame)
{
return(false);
}
}
}
catch (Exception exception)
{
Trace.TraceError($"Could not compare resource dictionaries: {exception} {Environment.NewLine} {exception.StackTrace}");
return(false);
}
return(true);
}
return(Uri.Compare(first.Source, second.Source, UriComponents.Host | UriComponents.Path, UriFormat.SafeUnescaped, StringComparison.OrdinalIgnoreCase) == 0);
}
public static Theme DetectTheme([NotNull] ResourceDictionary resourceDictionary)
{
if (resourceDictionary.IsNull())
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
if (DetectThemeFromResources(out var currentTheme, resourceDictionary))
{
return(currentTheme);
}
return(null);
}
public static void ApplyThemeResourcesFromTheme([NotNull] ResourceDictionary resources, [NotNull] Theme newTheme)
{
if (resources.IsNull())
{
throw new ArgumentNullException(nameof(resources));
}
if (newTheme.IsNull())
{
throw new ArgumentNullException(nameof(newTheme));
}
ApplyResourceDictionary(newTheme.Resources, resources);
}
public static Theme ChangeTheme([NotNull] ResourceDictionary resourceDictionary, [NotNull] Theme newTheme)
{
if (resourceDictionary.IsNull())
{
throw new ArgumentNullException(nameof(resourceDictionary));
}
if (newTheme.IsNull())
{
throw new ArgumentNullException(nameof(newTheme));
}
var oldTheme = DetectTheme(resourceDictionary);
return(ChangeTheme(resourceDictionary, oldTheme, newTheme));
}
/// <summary>
/// Determines whether the specified resource dictionary represents an <see cref="Theme"/>.
/// <para />
/// This might include runtime themes which do not have a resource uri.
/// </summary>
/// <param name="resources">The resources.</param>
/// <returns><c>true</c> if the resource dictionary is an <see cref="Theme"/>; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ArgumentNullException">resources</exception>
public static bool IsThemeDictionary([NotNull] ResourceDictionary resources)
{
if (resources.IsNull())
{
throw new ArgumentNullException(nameof(resources));
}
foreach (var styleKey in styleKeys)
{
// Note: do not use contains, because that will look in all merged dictionaries as well. We need to check
// out the actual keys of the current resource dictionary
if (!(from object resourceKey in resources.Keys
select resourceKey as string).Any(keyAsString => string.Equals(keyAsString, styleKey, StringComparison.Ordinal)))
{
return(false);
}
}
return(true);
}
private static bool AreResourceDictionarySourcesEqual(ResourceDictionary first, ResourceDictionary second)
{
if (first.IsNull() ||
second.IsNull())
{
return(false);
}
// If RD does not have a source, but both have keys and the first one has at least as many keys as the second,
// then compares their values.
if ((first.Source.IsNull() ||
second.Source.IsNull()) &&
first.Keys.Count > 0 &&
second.Keys.Count > 0 &&
first.Keys.Count >= second.Keys.Count)
{
try
{
foreach (var key in first.Keys)
{
var isTheSame = second.Contains(key) &&
Equals(first[key], second[key]);
if (!isTheSame)
{
return(false);
}
}
}
catch (Exception exception)
{
Trace.TraceError($"Could not compare resource dictionaries: {exception} {Environment.NewLine} {exception.StackTrace}");
return(false);
}
return(true);
}
return(Uri.Compare(first.Source, second.Source, UriComponents.Host | UriComponents.Path, UriFormat.SafeUnescaped, StringComparison.OrdinalIgnoreCase) == 0);
}