Placing and arranging widgets

So far, we've created a lot of widgets, but if you run the program you won't see any of them. Although our widgets all belong to the parent window, they haven't been placed on it yet. In this section, we'll learn how to arrange our widgets in the application window and set them to an appropriate size.

Layout classes

A layout object defines how child widgets are arranged on a parent widget. Qt offers a variety of layout classes, each of which has a layout strategy appropriate for different situations.

The workflow for using layout classes goes like this:

1. Create a layout object from an appropriate layout class
2. Assign the layout object to the parent widget's layout property...