Refactoring_to_improve_maintainability_and_blendability_using_IoC_part_1_04.cs

public class MainViewModelFactory
    : ViewModelFactory<MainViewModel, MainViewModelDesign>
{
}

public class MainViewModelDesign : MainViewModel
{
    public MainViewModelDesign()
        : base(new EventAggregator(), new DesignDatabase())
    {
    }

    public override void OnLocated(bool newInstance)
    {
#if DEBUG
        this.Stories.Add(
            new Story("The Windows Blog", "Upping our game..."));
        this.Stories.Add(
            new Story("Robot Overlords", "Nevada Passes Law..."));
        this.Stories.Add(
            new Story("TechCrunch", "eBay Acquired Magento..."));
        this.Stories.Add(
            new Story("Inside Facebook", "Facebook Testing..."));
        this.Stories.Add(
            new Story("FOSS Patents", "Eastman Kodak v..."));
#endif
    }
}

public class MainViewModel : BaseViewModel
{
    private IDatabase db = null;
    private IEventAggregator events = null;
    private Feed feed = null;

    public MainViewModel(IEventAggregator events, IDatabase db)
    {
        this.events = events;
        this.events.Subscribe(this);
        this.db = db;

        this.Stories = new ObservableCollection<Story>();
    }

    public override void OnLocated(bool newInstance)
    {
        LoadDatabase();
        GetFeedStories();
    }
}