Question

I am currently designing a new .NET application and would like to keep it UI independant.

Whilst I initally would like to use WPF, I would like to have the option of swapping the UI to ASP or WinForms if necessary.

In a layered design:

View – Interface Controller (ViewModel) – Model – Persistance

is it possible to design the Interface Controller so that it will work with different view technologies, or will I need to replace the interface controller at the same time as the View?

Answer 1

Take a look at my answer to the question “Silverlight with MVVM Inheritance: ModelView and View matching the Model”.

The answer I gave works for your situation too.

In a nutshell, I define the following general interfaces:

public interface IModel
{
}

public interface IViewModel
{
}

public interface IViewModel<M> : IViewModel
    where M : IModel
{
    void Bind(M model);
}

public interface IView
{
}

public interface IView<VM> : IView
    where VM : IViewModel
{
    void Bind(VM viewModel);
}

Which allow me to define specific interfaces like this:

public interface IPersonModel : IModel
{
}

public interface IPersonViewModel : IViewModel<IPersonModel>
{
}

public interface IPersonView : IView<IPersonViewModel>
{
}

By implementing your layers against these interfaces you can swap your implementation of the IView<VM> interface with WPF, Silverlight, Windows Forms or even ASP.Net.