The GtkBox widget arranges child widgets into a single row or column, depending upon the value of its #GtkOrientable:orientation property. Within the other dimension, all children are allocated the same size. Of course, the #GtkWidget:halign and #GtkWidget:valign properties can be used on the children to influence their allocation.
Fluent builder for gtk.box.Box
Fluent builder implementation template for gtk.box.Box
Module for Box class