The mode of the size group determines the directions in which the size
group affects the requested sizes of its component widgets.
GTK_SIZE_GROUP_NONE
group has no effect
GTK_SIZE_GROUP_HORIZONTAL
group affects horizontal requisition
GTK_SIZE_GROUP_VERTICAL
group affects vertical requisition
GTK_SIZE_GROUP_BOTH
group affects both horizontal and vertical requisition
The mode of the size group determines the directions in which the size group affects the requested sizes of its component widgets. GTK_SIZE_GROUP_NONE group has no effect GTK_SIZE_GROUP_HORIZONTAL group affects horizontal requisition GTK_SIZE_GROUP_VERTICAL group affects vertical requisition GTK_SIZE_GROUP_BOTH group affects both horizontal and vertical requisition