The TixSelect widget figure 1-10 provides you the same kind of facility that is available with the Tk radiobutton and checkbutton widgets. That is, TixSelect allows the user to select one or a few values out of many choices. However, TixSelect is superior because it allows you to layout the choices in much less space than what is required by the Tk radiobutton widgets. Also, TixSelect supports complicated selection rules. Because of these reasons, TixSelect is a primary choice for implementing toolbar buttons, which often have strict space requirements and complicated selection rules.