the width which is available for allocation, or -1 if none
location for storing the minimum height, or %NULL
location for storing the natural height, or %NULL
location for storing the baseline for the minimum height, or %NULL
location for storing the baseline for the natural height, or %NULL
3.10
Retrieves a widget’s minimum and natural height and the corresponding baselines if it would be given the specified @width, or the default height if @width is -1. The baselines may be -1 which means that no baseline is requested for this widget.
The returned request will be modified by the GtkWidgetClass::adjust_size_request and GtkWidgetClass::adjust_baseline_request virtual methods and by any #GtkSizeGroups that have been applied. That is, the returned request is the one that should be used for layout, not necessarily the one returned by the widget itself.