在我正在后面的代码中创建的新Groupbox中没有找到SetResourceReference

I want to set a reference to a Template in a groupbox I'm creating in the code behind.In a example I found, they mostly use SetResourceReference method. However, I see that this method doesn't seem to exist on the new Groupbox property in creating. XAML: I want to set a reference to a Template in a gr