private void DrawRowCell(UnityEngine.Rect rect, Column column, SceneReferenceItem item, RowGUIArgs args)
        {
            if (null == item)
            {
                return;
            }

            CenterRectUsingSingleLineHeight(ref rect);

            switch (column)
            {
            case Column.Icon:
            {
                GUI.DrawTexture(rect, Icons.Scene, ScaleMode.ScaleToFit);
                break;
            }

            case Column.Scene:
            {
                DefaultGUI.Label(rect, item.ScenePath, args.selected, args.focused);
                break;
            }

            case Column.StartupToggle:
            {
                var toggleRect  = rect;
                int toggleWidth = 20;
                toggleRect.x += rect.width * 0.5f - toggleWidth * 0.5f;

                bool toggleVal = EditorGUI.Toggle(toggleRect, item.IsStartup);
                if (toggleVal != item.IsStartup)
                {
                    item.IsStartup = toggleVal;

                    var project        = Application.AuthoringProject;
                    var sceneReference = new SceneReference {
                        SceneGuid = item.SceneGuid
                    };
                    if (toggleVal)
                    {
                        project.AddStartupScene(sceneReference);
                    }
                    else
                    {
                        project.RemoveStartupScene(sceneReference);
                    }
                    Repaint();
                }
                break;
            }
            }
        }
        private void ShowSceneReferenceContextMenu(SceneReferenceItem item)
        {
            if (item.SceneGuid == SceneReference.Null.SceneGuid)
            {
                return;
            }

            var project = Application.AuthoringProject;
            var menu    = new GenericMenu();

            menu.AddItem(new GUIContent($"Remove Scene from {project.Name}"), false, () =>
            {
                project.RemoveScene(new SceneReference {
                    SceneGuid = item.SceneGuid
                });
                Invalidate();
            });

            menu.ShowAsContext();
        }