expand is FALSE, then the preview's window
and buffer will be no larger than the size set with
gtkPreviewSize, and the data set will be centered
in the allocation if it is larger. If expand is TRUE
then the window and buffer will expand with the allocation;
the application is responsible for catching
the "size_allocate" signal and providing the data
appropriate for this size.
WARNING: gtk_preview_set_expand is deprecated and should not be used in newly-written code.
gtkPreviewSetExpand(object, expand)objectGtkPreview.expand