Sets our main struct and passes it to the parent class.
Allocates a new #GtkRequisition-struct and initializes its elements to zero.
Copies a #GtkRequisition.
Frees a #GtkRequisition.
Get the main Gtk struct
the main Gtk struct as a void*
the widget’s desired height
the widget’s desired width
the main Gtk struct
A #GtkRequisition-struct represents the desired size of a widget. See [GtkWidget’s geometry management section][geometry-management] for more information.