[StyleExtensions] Resources Attached Property

[kazo0]

It would be nice to have a DependencyProperty for Resources. Right now Resources is not a DP so you can't use it in a Setter for a style to say that a specific style should have certain resources defined.

It'd be cool to have an attached property that you can use in a Style.Setter to define a ResourceDictionary where you can put whatever you want. Then I guess we'd need to somehow inject that ResourceDictionary into the Resources of the root control of the ControlTemplate maybe?

One outstanding question is if it is at all possible to be able to access those resources from other Style.Setters on the same Style, sort of like in WPF.

Example:

<Style TargetType="XamlDisplay">
		<Style.Resources>
				<local:XamlFormatter x:Key="IndentedXamlFormatter" />
		</Style.Resources>
		<Setter Property="Formatter" Value="{StaticResource IndentedXamlFormatter}" />
		<Setter Property="Template">
		...
		</Setter>
</Style>

[Xiaoy312]

Style.Resources wont be possible, but StyleEx.Resources or utu:Style.Resources could be
but ultimately you just want to set the Control.Resources, so you should just create a attached-dp which you use directly to affect that property in the code-behind (as it is not a dp, you cant really use setter with it):

<Setter Property="utu:StyleExtensions.Resources" Value="path-to-my-custom.xaml" />
---
private void StyleExtensions::OnResourcesChanged(object sender, DependencyPropertyCangedArgs e) =>
	(sender as Control).Resources = e.NewValue is string path
		? new ResourceDictionary { Source = path };
		: null;

[Xiaoy312]

directly inline collection item in an attached-dp likely will be problematic too, for both ours and uwp's parser

[Marc-Antoine-Soucy]

What I have right now in the Xaml:

<RadioButton GroupName="RadioButton_Material_B"
			Content="Overridden Radio Button Style - Unchecked"
			Style="{StaticResource MaterialRadioButtonStyle}"
			local:FrameworkElementExtensions.ResourcePath="ms-appx:///Views/ControlResourcesOverride/Material/RadioButton.xaml" />

You can also change it in a style

<Setter Property="local:FrameworkElementExtensions.ResourcePath"
	     Value="ms-appx:///Views/ControlResourcesOverride/Material/Button.xaml" />

the "ms-appx:///" could be added in the extension code, but I'm not sure if there are times where people would want to use a different kind of prefix.
As for the code in the extension, it's basically this:

private static void OnResourcePathChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
	var control = d as FrameworkElement;
	if (control != null)
	{
		var resourcePath = (string)e.NewValue;
		AddResourcesFromPath(control, resourcePath);
	}
}

private static void AddResourcesFromPath(FrameworkElement control, string resourcePath)
{
	// Load the resource dictionary
	var resources = new ResourceDictionary()
	{
		Source = new Uri(resourcePath, UriKind.RelativeOrAbsolute)
	};

	// Add or replace the resources in this control's resource dictionary
	foreach (var key in resources.Keys)
	{
		if (control.Resources.ContainsKey(key))
                {
			control.Resources[key] = resources[key];
                }
		else
                {
			control.Resources.Add(key, resources[key]);
                }
	}
}

Maybe we don't want that part?

if (control.Resources.ContainsKey(key))
{
	control.Resources[key] = resources[key];
}

[francoistanguay]

just want to set the Con

I would probably put it in ControlExtensions.Resources

[agneszitte]

don't forget the documentation that needs to come with it please

[kazo0]

@Marc-Antoine-Soucy My thinking was more that we would be able to do something like:

<Style TargetType="Button">
	<Setter Property="utu:ControlExtensions.Resources">
		<Setter.Value>
			<ResourceDictionary>
				<StaticResource x:Key="ButtonBackground" ResourceKey="MyRedBrush" />
				<!-- OR -->
				<SolidColorBrush x:Key="ButtonBackground" Color="Red" />
				<!-- OR -->
				<ResourceDictionary.ThemeDictionaries>
					<!--- etc... -->
				</ResourceDictionary.ThemeDictionaries>
			</ResourceDictionary>
			<!-- OR -->
			<ResourceDictionary Source="....." />
		</Setter.Value>

	<Setter Property="Template">
	...
	</Setter>
</Style>

Something like that should theoretically work right @Xiaoy312 ?

[Xiaoy312]

in theory, yes?