Question

I have a DataTemplate inside a global/shared ResourceDictionary like this which targets a DataType:

<DataTemplate DataType="{x:Type foo:Bar}">
    <!-- My DataTemplate visual tree goes here... -->
</DataTemplate>

This DataTemplate replaces my all foo:Bar types on all my Views (UserControls/Windows). What I want to do is to apply this template to only certain views, keeping the other views are not affected by this DataTemplate. I can copy this DataTemplate to Resources sections of each of these view, but I don’t want to copy/paste the contents of the DataTemplate which would result in maintenance headaches.

Answer 1

What you are using here is called implicit data template. And you are asking for an explicit one. To accomplish this you could use explicit resource key:

<DataTemplate x:Key="MyStyle" DataType="{x:Type foo:Bar}">
    <!-- My DataTemplate visual tree goes here... -->
</DataTemplate>

And later in xaml:

<ContentPresenter ContentTemplate="{StaticResource MyStyle}" .../>

Another solution would be one resource dictionary (with implicit data templates) used via Merged Dictiories inside appropriate Control/Page.

I prefer the first approach, because it’s easier to maintain (implicit styles are way harder to trace).