New Post: Getting container in View Model

I have a view that defines a view model in xaml:

<UserControl.DataContext>
        <VM:MainMenuViewModel />
    </UserControl.DataContext>ext>

Then my VM:

   public class MainMenuViewModel
    { 
        private readonly IUnityContainer container;

        public MainMenuViewModel(IUnityContainer _container)
        {
            container = _container; 
        }
.......

I get an error saying that no accessible constructor exists when the view runs because it isn't injecting the IUnityContainer. What is the "proper" way to access the container from a view model? Thanks.