am i using dependency incection with unity the right way?
public interface IUserRepository
{
    List<User> getAll();
}

public class UserRepository : IUserRepository
{

    private MyDbContext db;

    public UserRepository(MyDbContext db)
    {
        this.db = db;
    }

    public List<DomainModel.User> getAll()
    {
        return db.Users.ToList();
    }
}

public class FakeUserRepository : IUserRepository
{
    private List<User> userSet;

    public FakeUserRepository()
    {
        // Fake Data
        userSet = new List<User>();
        userSet.Add(new User { Username = "john", Active = true, EMail = "john@ann.net", Password = "supersecret" });
        userSet.Add(new User { Username = "ashley", Active = true, EMail = "ashley@ann.net", Password = "supersecret" });
        userSet.Add(new User { Username = "kaidan", Active = true, EMail = "kaidan@ann.net", Password = "supersecret" });
        userSet.Add(new User { Username = "tali", Active = true, EMail = "tali@ann.net", Password = "supersecret" });

    }

    public List<DomainModel.User> getAll()
    {
        return userSet;
    }

}

// To Keep it simple, i skipped the IDisposable part ;)

public class UnitOfWork
{
    MyDbContext db;
    private IUserRepository userRepository;
    UnityContainer container = new UnityContainer();
    public UnitOfWork(bool fake = false)
    {
        if (fake)
        {
            container.RegisterType<IUserRepository, FakeUserRepository>();
        }
        else
        {
            db =  = new MyDbContext();
            container.RegisterType<IUserRepository, UserRepository>(new InjectionConstructor(db));
        }
    }


    public IUserRepository UserRepository
    {
        get
        {
            if (userRepository == null)
            {
                userRepository = container.Resolve<IUserRepository>();
            }
            return userRepository;
        }
    }

    public void Save()
    {
        db.SaveChanges();
    }
}