void InitializeComponent()
        {
            collapseButton        = new PaddinglessButton();
            collapseButton.Click += CollapseButton_Click;

            SplitterMoved += CollapsibleSplitContainer_SplitterMoved;
        }
        /// <summary>
        /// Dispose controls resources.
        /// </summary>
        /// <param name="disposing"></param>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                if (collapseButton != null)
                {
                    collapseButton.Click -= CollapseButton_Click;
                    collapseButton.Dispose();
                    collapseButton = null;
                }
            }

            base.Dispose(disposing);
        }