After we have created the TixSelect widget, we can create the button subwidgets inside the TixSelect widget by the add widget command (lines 2-4 of program 1-11).
The first argument to the add command is the name of the button subwidget. Additional arguments can be given in option-value pairs to configure the appearance of the button subwidget. These option-value pairs can be any of those accepted by a normal TK button widget. As shown in program 1-11, we use the -text option to put appropriate text strings over the three button subwidgets.
Notice that we also set the -width option of all the button subwidgets to 6 characters. This way, the three buttons will have the same width. If we didn't set the -width option for the button widgets, they will have different widths, depending on their text string, and the result would look less esthetically pleasing than buttons with same widths.
The output of program 1-11 is shown in figure 1-12
(Figure 1-12) The TixSelect Widget