GtkAcceleratorTable has been replaced with GtkAccelGroup.

GtkMenuFactory has been replaced with GtkItemFactory, although a version of GtkMenuFactory is currently still provided to ease the migration phase.

The GtkTypeInfo structures used in the gtk_*_type_init() functions have changed a bit, the old format:

      GtkTypeInfo bin_info =
      {
        "GtkBin",
        sizeof (GtkBin),
        sizeof (GtkBinClass),
        (GtkClassInitFunc) gtk_bin_class_init,
        (GtkObjectInitFunc) gtk_bin_init,
        (GtkArgSetFunc) NULL,
        (GtkArgGetFunc) NULL,
      };

needs to be converted to:

      static const GtkTypeInfo bin_info =
      {
        "GtkBin",
        sizeof (GtkBin),
        sizeof (GtkBinClass),
        (GtkClassInitFunc) gtk_bin_class_init,
        (GtkObjectInitFunc) gtk_bin_init,
        /* reserved_1 */ NULL,
        /* reserved_2 */ NULL,
        (GtkClassInitFunc) NULL,
      };

the GtkArgSetFunc and GtkArgGetFunc functions are not supported from the type system anymore, and you should make sure that your code only fills in these fields with NULL and doesn't use the deprecated function typedefs (GtkArgSetFunc) and (GtkArgGetFunc) anymore.

A number of GTK+ functions were renamed. For compatibility, gtkcompat.h #define's the old 1.0.x function names in terms of the new names. To assure your GTK+ program doesn't rely on outdated function variants, compile your program with -DGTK_DISABLE_COMPAT_H to disable the compatibility aliases. Here is the list of the old names and replacements:

Note that gtk_style_apply_default_background() has an additional argument, set_bg. This parameter should be FALSE if the background is being set for a NO_WINDOW widget, otherwise TRUE.

During the development phase of the 1.1.x line of GTK+ certain functions were deprecated and later removed. Functions affected are:

Note that gtk_entry_adjust_scroll() is no longer needed as GtkEntry should automatically keep the scroll adjusted properly.

Additionally, all gtk_*_interp() functions were removed. gtk_*_full() versions were provided as of GTK+ 1.0 and should be used instead.

GtkButton has been changed to derive from GtkBin. To access a button's child, use GTK_BIN (button)->child, instead of the old GTK_BUTTON (button)->child.

The selection API has been slightly modified: gtk_selection_add_handler() and gtk_selection_add_handler_full() have been removed. To supply the selection, one now registers the targets one is interested in with:

  void gtk_selection_add_target (GtkWidget           *widget, 
	  	                 GdkAtom              selection,
			         GdkAtom              target,
			         guint                info);

or:

  void gtk_selection_add_targets (GtkWidget           *widget, 
	  			  GdkAtom              selection,
				  GtkTargetEntry      *targets,
				  guint                ntargets);

When a request for a selection is received, the new "selection_get" signal will be called:

   void  "selection_get"           (GtkWidget          *widget,
				    GtkSelectionData   *selection_data,
				    guint               info,
				    guint               time);

A "time" parameter has also been added to the "selection_received" signal.

  void  "selection_received"       (GtkWidget          *widget,
				    GtkSelectionData   *selection_data,
				    guint               time);

The old drag and drop API has been completely removed and replaced. See the reference documentation for details on the new API.

Support for Themes has been added. In general, this does not affect application code, however, a few new rules should be observed:

The GtkScrolledWindow widget no longer creates a GtkViewport automatically. Instead, it has been generalized to accept any "self-scrolling" widget.

The self-scrolling widgets in the GTK+ core are GtkViewport, GtkCList, GtkCTree, GtkText, and GtkLayout. All of these widgets can be added to a scrolled window as normal children with gtk_container_add() and scrollbars will be set up automatically.

To add scrollbars to a non self-scrolling widget, (such as a GtkList), first add it to a viewport, then add the viewport to a scrolled window. The scrolled window code provides a convenience function to do this:

  void gtk_scrolled_window_add_with_viewport (GtkScrolledWindow *scrollwin,
					      GtkWidget         *child);

This does exactly what it says - it creates a viewport, adds the child widget to it, then adds the viewport to the scrolled window.

The scrollbars have been removed from the GtkCList and GtkCTree, because they are now scrolled by simply adding them to a scrolled window. The scrollbar policy is set on the scrolled window with gtk_scrolled_window_set_policy() and not on the child widgets (e.g. GtkCList's gtk_clist_set_policy() was removed).

The "main loop" of GTK+ has been moved to GLib. This should not affect existing programs, since compatibility functions have been provided. However, you may want to consider migrating your code to use the GLib main loop directly.

the GTK_BASIC flag was removed, and with it the corresponding macro and function GTK_WIDGET_BASIC() and gtk_widget_basic().

All freeze/thaw methods are now recursive - that is, if you freeze a widget n times, you must also thaw it n times. Therefore, if you have code like:

  gboolean frozen;
  frozen = GTK_CLIST_FROZEN (clist);
  gtk_clist_freeze (clist);
  [...]
  if (!frozen)
    gtk_clist_thaw (clist);

it will not work anymore. It must be, simply:

  gtk_clist_freeze (clist);
  [...]
  gtk_clist_thaw (clist);

The thread safety in GTK+ 1.2 is slightly different than that which appeared in early versions in the 1.1 development track. The main difference is that it relies on the thread primitives in GLib, and on the thread-safe GLib main loop.

This means:

Prior to GTK+ 1.2, there were two conflicting interpretations of widget->requisition. It was either taken to be the size that the widget requested, or that size modified by calls to gtk_widget_set_usize(). In GTK+ 1.2, it is always interpreted the first way.

Container widgets are affected in two ways by this: