Item Template: how to define the "BuildAction"

Hello,

I'm trying to build an item template for the language I'm using in Visual Studio 2015.

I need a template for a WPF window, and the "BuildAction" entry in the "File Properties" of the item should be set to "Page", so the compiler builds the BAML file.

This is what I currently have (only the relevant line):

<ProjectItem TargetFileName="$fileinputname$.xaml" ReplaceParameters="true" CustomTool="MSBuild:Compile">WPFWindow.xaml</ProjectItem>

The item is added correctly, but the "BuildAction" has a value of "Content" instead of "Page".

Unfortunately, I was noch able to find documentation how to set this type from my item template (currently, I need only "Page", but there are other types I need to setup to speed up my development.

Thank you for any help!

Wolfgang

P.S. the language I'm using is X#, an Xbase dialect that uses the Roslyn platform