The level of granularity for the font selection.
Depending on this value, the PangoFontDescription that is returned by method@Gtk.FontDialogButton.get_font_desc will have more or less fields set.
PangoFontDescription
4.10
Select a font family
Select a font face (i.e. a family and a style)
Select a font (i.e. a face with a size, and possibly font variations)
Select a font and font features
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
Returns an array containing the constants of this enum type, in the order they're declared.