c# - WPF ユーザーコントロール WindowStartupLocation

Question

WindowStartupLocationのプロパティを取得する方法WindowはUserControl?

public partial class ActivityDetailsView : UserControl
{
    public ActivityDetailsView(ActivityDetailsViewModel viewModel)
    {
        InitializeComponent();
        DataContext = viewModel;
        Loaded += ActivityDetailsView_Loaded;
        JobOrderLineItem.SelectionChanged += JobOrder_SelectionChanged;

        //this.WindowStartupLocation doesnt exist
    }
}