Implementing the View menu

Tkinter offers the following three varieties of menu items:

• Checkbutton menu items: These let you make a yes/no choice by checking/unchecking the menu item
• Radiobutton menu items: These let you choose an option from many different options
• Cascade menu items: These menu items only opens up to show another list of choices

The following View menu shows all of these three types of menu items in action:

The first three menu items in the View menu let users make a definite yes or no choice by checking or unchecking them. These are examples of the Checkbutton menu.

The Themes menu item in the preceding screenshot is an example of a Cascade menu. Hovering over this cascade menu simply opens another list of menu items. However, we can also bind a menu item by using the postcommand=callback option. This can be used to manage something just before bringing up the cascading menu item's contents and is often used for dynamic list creation.

Within the cascade menu, you are presented...