public void When_LinkedResDict_ThemeUpdated()
{
const string TestBrush = nameof(TestBrush);
const string TestThemeColor = nameof(TestThemeColor);
const string Light = nameof(Light);
const string Dark = nameof(Dark);
var theme = ResourceDictionary.GetActiveTheme();
try
{
// setup
ResourceDictionary.SetActiveTheme("Light");
// initialize source res-dict
var parserContext = new XamlParseContext();
var dontcare = new object();
var source = new ResourceDictionary()
{
IsParsing = true,
ThemeDictionaries =
{
[Light] = new WeakResourceInitializer(dontcare, that => new ResourceDictionary {
[TestThemeColor] = Colors.Red,
}),
[Dark] = new WeakResourceInitializer(dontcare, that => new ResourceDictionary {
[TestThemeColor] = Colors.Blue,
}),
},
[TestBrush] = new WeakResourceInitializer(dontcare, that =>
{
var brush = new SolidColorBrush();
ResourceResolverSingleton.Instance.ApplyResource(brush, SolidColorBrush.ColorProperty, TestThemeColor, true, parserContext);
return(brush);
})
};
source.CreationComplete();
// making a copy from source
var copy = new ResourceDictionary();
copy.CopyFrom(source);
// retrieve the "TestBrush" from each res-dict while also materializing it in both the source and in the copy
var materialized1 = (SolidColorBrush)source[TestBrush];
var materialized2 = (SolidColorBrush)copy[TestBrush];
var materialized2Color = materialized2.Color;
// set active theme and update the copy res-dict
ResourceDictionary.SetActiveTheme(Dark);
copy.UpdateThemeBindings(Windows.UI.Xaml.Data.ResourceUpdateReason.ThemeResource);
// retrieve the "TestBrush" again from each res-dict
var materialized3 = (SolidColorBrush)source[TestBrush];
var materialized4 = (SolidColorBrush)copy[TestBrush];
// validation
Assert.AreEqual(false, ReferenceEquals(materialized1, materialized2)); // we are expecting these to be different, as the CopyFrom should copy them as WeakResourceInitializer...
Assert.AreEqual(false, ReferenceEquals(materialized3, materialized4)); // ^same
Assert.AreNotEqual(materialized2Color, materialized4.Color); // check the theme change is actually applied (otherwise it would void the next check)
Assert.AreEqual(materialized3.Color, materialized4.Color); // check the theme change is propagated to the source res-dict
}
finally
{
// clean up
ResourceDictionary.SetActiveTheme(theme);
}
}