Question

I’ve been learning the MVVM pattern with Josh Smith’s article and I want to create a classic layout with some links to the right (managed with commands) so when I click one I can show my view to the right into a tab control (inside it there is a ContentControl).

This is simple when I use a DataTemplate with the specific View and ViewModel I want to show on screen like this.

<!-- this section into my MainWindow's resources file -->
<DataTemplate xmlns:vm='clr-namespace:WpfFramework.ViewModels'
              xmlns:vw='clr-namespace:WpfFramework.Views'
              DataType="{x:Type vm:MySpecificViewModel }" >        
    <vw:MySpecificView />
</DataTemplate>

But, I want something more generic. I mean that my mainWindow should not know a specific View nor a specific ViewModel. It should only know that it binds to some commands and has a tab control which shows "some view". Every sample including Josh Smith’s article seems to have limited universe of views and viewmodels, that’s great with a sample.

So, how can I tell my ContentControl that some view (with its corresponding viewModel) is gonna be there without being so specific (without "burning" into the mainView the concrete types)?

best regards
Rodrigo

PD. I have tryed with base a ViewModel and Base View but it doesn’t seem to work.

Answer 1

In your main View, bind a ContentControl to a generic ViewModelBase property

<ContentControl Content="{Binding CurrentPage}" />

CurrentPage would be defined in the main ViewModel as a ViewModelBase object, and to switch pages you simply set CurrentPage to whatever you want.

So when you click on something like the HomePageCommand, the main ViewModel would execute CurrentPage = new HomePageViewModel(); providing that HomePageViewModel inherits from ViewModelBase.

I wrote something a little while ago that shows some samples here if you’re interested