Autofac: Registering types with dependencies

Question

I'm trying to register my WPF views with their corresponding viewmodels and avoid having to use code behind.

So far my code would look like this:

 builder.Register(c =>
    {
        PageA page = new PageA();
        page.DataContext = c.Resolve<PageAViewModel>;
        return page;
    });

    builder.Register(c =>
    {
        PageB page = new PageB();
        page.DataContext = c.Resolve<PageBViewModel>;
        return page;
    });

Is there are a more dynamic way to avoid having to write these lines for all views/pages? (if possible without using Service locator pattern).

Answer 1

You can create a generic method that will register your types :

public static class RegistrationExtension
{

    public static IRegistrationBuilder<TPage, ConcreteReflectionActivatorData, SingleRegistrationStyle> 
        RegisterPage<TPage, TViewModel>(this ContainerBuilder builder)
        where TPage : IPage
    {
        return builder.RegisterType<TPage>()
                      .OnActivated(e =>
                      {
                          e.Instance.DataContext = e.Context.Resolve<TViewModel>();
                      });

    }
}

and then register your pages like this :

builder.RegisterPage<PageA, PageAViewModel>();