Creates and initializes child widgets defined in templates.
This function must be called in the instance initializer for any class which assigned itself a template using [ [email protected]_template].
It is important to call this function in the instance initializer of a `GtkWidget` subclass and not in `GObject.constructed()` or `GObject.constructor()` for two reasons:
A good rule of thumb is to call this function as the first thing in an instance initialization function.
this |
a `GtkWidget` |