This allows a widget to tell its parent container whether
it prefers to be allocated in gtk.types.SizeRequestMode.HeightForWidth or
gtk.types.SizeRequestMode.WidthForHeight mode.
gtk.types.SizeRequestMode.HeightForWidth means the widget prefers to have
#GtkWidgetClass.get_preferred_width() called and then
#GtkWidgetClass.get_preferred_height_for_width().
gtk.types.SizeRequestMode.ConstantSize disables any height-for-width or
width-for-height geometry management for a said widget and is the
default return.
It’s important to note (as described below) that any widget
which trades height-for-width or width-for-height must respond properly
to both of the virtual methods #GtkWidgetClass.get_preferred_height_for_width()
and #GtkWidgetClass.get_preferred_width_for_height() since it might be
queried in either #GtkSizeRequestMode by its parent container.
This allows a widget to tell its parent container whether it prefers to be allocated in gtk.types.SizeRequestMode.HeightForWidth or gtk.types.SizeRequestMode.WidthForHeight mode. gtk.types.SizeRequestMode.HeightForWidth means the widget prefers to have #GtkWidgetClass.get_preferred_width() called and then #GtkWidgetClass.get_preferred_height_for_width(). gtk.types.SizeRequestMode.ConstantSize disables any height-for-width or width-for-height geometry management for a said widget and is the default return. It’s important to note (as described below) that any widget which trades height-for-width or width-for-height must respond properly to both of the virtual methods #GtkWidgetClass.get_preferred_height_for_width() and #GtkWidgetClass.get_preferred_width_for_height() since it might be queried in either #GtkSizeRequestMode by its parent container.