private void AddUndoButton(ToolboxLayoutDefinitionStandardToolsButtonsButton buttonLayout)
{
this.undoButton = new Button(
this.GraphicsDisplay,
new ButtonDefinition(buttonLayout, this.Scale, new ImageType[] { ImageType.UndoButton }, ImageType.UndoButtonDisabled));
this.undoButton.Enabled = false;
this.undoButton.ButtonPressed += (sender, e) =>
{
this.OnUndoSelected(EventArgs.Empty);
};
this.AddTool(this.undoButton);
}