RoleEditorWindow.xaml 的交互逻辑
 public static bool Edit(Window parent, VideoRole role)
 {
     var window = new RoleEditorWindow() { Owner = parent };
     window.ViewModel.ReadFromObject(role);
     if (window.ShowDialog() == true)
     {
         window.ViewModel.WriteToObject(role);
         return true;
     }
     return false;
 }