public LayoutPartViewModel(LayoutPart layoutPart, ILayoutPartPresenter layoutPartPresenter, ILayoutPartContent parent = null)
		{
			LayoutPart = layoutPart;
			LayoutPartPresenter = layoutPartPresenter;
			Content = LayoutPartPresenter.CreateContent((ILayoutProperties)LayoutPart.Properties);
			IconSource = LayoutPartPresenter.IconSource;
			Title = LayoutPart.Title ?? LayoutPartPresenter.Name;
			if (Content is ILayoutPartContent)
				((ILayoutPartContent)Content).SetLayoutPartContainer(this);
			Parent = parent;
		}
		public LayoutPartViewModel(LayoutPart layoutPart, ILayoutPartPresenter layoutPartPresenter)
		{
			LayoutPart = layoutPart;
			LayoutPartPresenter = layoutPartPresenter;
			Content = LayoutPartPresenter.CreateContent(LayoutPart.Properties);
		}