Support separators in combo boxes and more generally in tree views

Support separators in combo boxes and more generally in tree views

2004-07-07  Matthias Clasen  <mclasen@redhat.com>

	Support separators in combo boxes and more generally in tree
	views  (#135873):

	* gtk/gtkcombobox.h:
	* gtk/gtkcombobox.c (gtk_combo_box_get_row_separator_column):
	* gtk/gtkcombobox.c (gtk_combo_box_set_row_separator_column):
	Add a ::row-separator-column property with getter and setter,
	which can indicate a boolean model column to determine which
	rows are separators.

	* gtk/gtkcombobox.c: Display separator rows as separator menu
	items in menu mode, and by using the new treeview separator
	functionality in list mode.

	* gtk/gtktreeview.h:
	* gtk/gtktreeview.c (gtk_tree_view_get_row_separator_func):
	* gtk/gtktreeview.c (gtk_tree_view_set_row_separator_func):
	Add a callback to determine whether a row is a separator.

	* gtk/gtktreeview.c (gtk_tree_view_bin_expose):
	* gtk/gtktreeview.c (gtk_tree_view_create_row_drag_icon):
	* gtk/gtktreeview.c (validate_row): Use the new callback
	to determine whether a row is a separator, and draw it
	as a separator then. Since separators should take up less
	vertical space than regular rows, this requires removing
	the redundant MAX(...,expander_size) calls which appear in
	many places. Instead, the MAX() is now only done in
	validate_row(), and only if the row is not a separator.
	To catch possible side effects of this intrusive change,
	I have left EXPANDER_MAX() calls in place of the MAX() calls
	which will emit a warning if something breaks. They should
	be removed before 2.6.

	* gtk/gtktreeselection.c (row_is_selectable): Don't let
	separator rows be selected.

	* tests/testcombo.c (create_blaat): Add a separator column.