/// <summary>
        /// Handles hwen a filter is added to the collection.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="MapDrawFilterHelperCollectionEventArgs"/> instance containing the event data.</param>
        void _filterCollection_Added(MapDrawFilterHelperCollection sender, MapDrawFilterHelperCollectionEventArgs e)
        {
            // Add the new filter to the ToolBarControl's DropDownItems

            var ftsi = new FilterToolStripItem(e.Filter, e.FilterName);

            ftsi.CheckedChanged += ftsi_CheckedChanged;

            _tsFilters.Add(e.Filter, ftsi);

            var s = ToolBarControl.ControlSettings.AsSplitButtonSettings();

            s.DropDownItems.Insert(0, ftsi);
        }
        /// <summary>
        /// Handles hwen a filter is added to the collection.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="MapDrawFilterHelperCollectionEventArgs"/> instance containing the event data.</param>
        void _filterCollection_Added(MapDrawFilterHelperCollection sender, MapDrawFilterHelperCollectionEventArgs e)
        {
            // Add the new filter to the ToolBarControl's DropDownItems

            var ftsi = new FilterToolStripItem(e.Filter, e.FilterName);
            ftsi.CheckedChanged += ftsi_CheckedChanged;

            _tsFilters.Add(e.Filter, ftsi);

            var s = ToolBarControl.ControlSettings.AsSplitButtonSettings();
            s.DropDownItems.Insert(0, ftsi);
        }