private void lbItems_SelectedIndexChanged(object sender, EventArgs e)
        {
            var selected = (Supplier)lbItems.Items[lbItems.SelectedIndex];
            var view     = new SupplierView(_manager, lbItems, selected);

            view.Anchor = Constants.FullScreenStyles;
            view.Width  = this.rightPanel.Width;
            this.rightPanel.Controls.Clear();
            this.rightPanel.Controls.Add(view);
        }
        private void btNew_Click(object sender, EventArgs e)
        {
            var view = new SupplierView(_manager, lbItems, new Supplier()
            {
                Id = 0
            });

            view.Anchor = Constants.FullScreenStyles;
            view.Width  = this.rightPanel.Width;
            this.rightPanel.Controls.Clear();
            this.rightPanel.Controls.Add(view);
        }