ImageGlass.frmMain.mnuMainThumbnailBar_Click C# (CSharp) Method

        private void mnuMainThumbnailBar_Click(object sender, EventArgs e)
        {
            GlobalSetting.IsShowThumbnail = !GlobalSetting.IsShowThumbnail;
            sp1.Panel2Collapsed = !GlobalSetting.IsShowThumbnail;
            btnThumb.Checked = GlobalSetting.IsShowThumbnail;

            if (GlobalSetting.IsShowThumbnail)
            {
                //show
                var tb = new ThumbnailItemInfo(GlobalSetting.ThumbnailDimension, GlobalSetting.IsThumbnailHorizontal);
                sp1.Panel2MinSize = tb.TotalDimension;

                if (GlobalSetting.IsThumbnailHorizontal)
                {
                    // BOTTOM
                    sp1.SplitterWidth = 1;
                    sp1.Orientation = Orientation.Horizontal;
                    sp1.SplitterDistance = sp1.Height - tb.TotalDimension;
                    thumbnailBar.View = ImageListView.View.Gallery;

                    //hide splitter color
                    sp1.BackColor = Color.White;
                }
                else
                {
                    // RIGHT
                    sp1.IsSplitterFixed = false; //Allow user to resize
                    sp1.SplitterWidth = 2;
                    sp1.Orientation = Orientation.Vertical;
                    sp1.SplitterDistance = sp1.Width - Math.Max(GlobalSetting.ThumbnailBarWidth, tb.TotalDimension);
                    thumbnailBar.View = ImageListView.View.Thumbnails;

                    //theme for splitter of horizontal bar
                    sp1.BackColor = thumbnailBar.BackColor;
                }
            }
            else
            {
                //Save thumbnail bar width when closing
                if (!GlobalSetting.IsThumbnailHorizontal)
                {
                    GlobalSetting.ThumbnailBarWidth = sp1.Width - sp1.SplitterDistance;
                }
            }
            mnuMainThumbnailBar.Checked = GlobalSetting.IsShowThumbnail;
            SelectCurrentThumbnail();
        }