public Requisition size_request ()
Warning: size_request is deprecated since "3.0".
This function is typically used when implementing a Container subclass.
Use get_preferred_size instead.
Obtains the preferred size of a widget. The container uses this information to arrange its child widgets and decide what size allocations to give them with size_allocate.
You can also call this function from an application, with some caveats. Most notably, getting a size request requires the widget to be associated with a screen, because font information may be needed. Multihead-aware applications should keep this in mind.
Also remember that the size request is not necessarily the size a widget will actually be allocated.
a Requisition to be filled in