gtk2/docs/Changes-2.0.txt

Incompatible Changes from GTK+-1.2 to GTK+-1.4:

* The gdk_time* functions have been removed. This functionality
  has been unused since the main loop was moved into GLib
  prior to 1.2. 

* The signature for GtkPrintFunc (used for gtk_item_factory_dump_items)
  has been changed to take a 'const gchar *' instead of 'gchar *', to
  match what we do for glib, and other similar cases.

* The detail arguments in the GtkStyleClass structure are now 'const gchar *'.

* gtk_paned_set_gutter_size() has been removed, since the small handle tab
  has been changed to include the entire area previously occupied by
  the gutter.

* GDK no longer selects OwnerGrabButtonMask for button presses. This means  
  that the automatic grab that occurs when the user presses a button
  will have owner_events = FALSE, so all events are redirected to the
  grab window, even events that would normally go to  other windows of the
  window's owner.

* GtkColorSelectionDialog has now been moved into it's own set of files,
  gtkcolorseldialog.c and gtkcolorseldialog.h.

* gtk_widget_shape_combine_mask() now keeps a reference count on the 
  mask pixmap that is passed in.

* Type system changes:
  - GTK_TYPE_OBJECT is not a fundamental type anymore. Type checks of the
    style (GTK_FUNDAMENTAL_TYPE (some_type) == GTK_TYPE_OBJECT)
    will not work anymore. As a replacement, (GTK_TYPE_IS_OBJECT (some_type))
    can be used now.
  - The following types vanished: GTK_TYPE_ARGS, GTK_TYPE_CALLBACK,
    GTK_TYPE_C_CALLBACK, GTK_TYPE_FOREIGN. The corresponding GtkArg
    fields and field access macros are also gone.
  - The following type aliases vanished: GTK_TYPE_FLAT_FIRST,
    GTK_TYPE_FLAT_LAST, GTK_TYPE_STRUCTURED_FIRST, GTK_TYPE_STRUCTURED_LAST.
  - The type macros GTK_TYPE_MAKE() and GTK_TYPE_SEQNO() vanished, use of
    GTK_FUNDAMENTAL_TYPE() is discouraged. Instead, the corresponding GType
    API should be used: G_TYPE_FUNDAMENTAL(), G_TYPE_DERIVE_ID(),
    G_TYPE_BRANCH_SEQNO(). Note that the GLib type system doesn't build new
    type ids based on a global incremental sequential number anymore, but
    numbers new type ids sequentially per fundamental type branch.
  - The following type functions vanished/were replaced:
    Old Function		 Replacement
    gtk_type_query()		 - being investigated -
    gtk_type_set_varargs_type()	 -
    gtk_type_get_varargs_type()	 -
    gtk_type_check_object_cast() g_type_check_instance_cast()
    gtk_type_check_class_cast()	 g_type_check_class_cast()
    gtk_type_describe_tree()	 -
    gtk_type_describe_heritage() -
    gtk_type_free()		 -
    gtk_type_children_types()	 g_type_children()
    gtk_type_set_chunk_alloc()	 GTypeInfo.n_preallocs
    gtk_type_register_enum()	 g_enum_register_static()
    gtk_type_register_flags()	 g_flags_register_static()
    gtk_type_parent_class()	 g_type_parent() / g_type_class_peek_parent()
    Use of g_type_class_ref() / g_type_class_unref() and g_type_class_peek()
    is recommended over usage of gtk_type_class().
    Use of g_type_register_static() / g_type_register_dynamic() is recommended
    over usage of gtk_type_unique().

* Object system changes:
  GtkObject derives from GObject, so is not the basic object type anymore.
  This imposes the following source incompatible changes:
  - GtkObject has no klass field anymore, an object's class can be retrived
    with the object's coresponding GTK_<OBJECT>_GET_CLASS (object) macro.
  - GtkObjectClass has no type field anymore, a class's type can be retrived
    with the GTK_CLASS_TYPE (class) macro.
  - GtkObjectClass does not introduce the finalize() and shutdown() methods
    anymore. While shutdown() is intended for GTK+ internal use only, finalize()
    is required by a variety of object implementations. GObjectClass.finalize
    should be overriden here, e.g.:
    static void gtk_label_finalize (GObject *gobject)
    {
      GtkLabel *label = GTK_LABEL (gobject);
      
      G_OBJECT_CLASS (parent_class)->finalize (object);
    }
    static void gtk_label_class_init (GtkLabelClass *class)
    {
      GObjectClass *gobject_class = G_OBJECT_CLASS (class);
      
      gobject_class->finalize = gtk_label_finalize;
    }

  - the GtkObject::destroy signal can now be emitted multiple times on an object.
    ::destroy implementations should check that make sure that they take this
    into account, by checking to make sure that resources are there before
    freeing them. For example:
    if (object->foo_data)
      { 
        g_free (object->foo_data);
        object->foo_data = NULL;
      }

    Also, ::destroy implementations have to release object references that
    the object holds. Code in finalize implementations such as:
    if (object->adjustment)
      {
        gtk_object_unref (object->adjustment);
        object->adjustment = NULL;
      }
    have to be moved into the ::destroy implementations. The reason for doing
    this is that all object reference cycles should be broken at destruction 
    time.

- Inserting and deleting text in GtkEntry though functions such
  as gtk_entry_insert_text() now leave the cursor at its original
  position in the text instead of moving it to the location of
  the insertion/deletion.

- The ->label field of GtkFrame widgets has been removed. (As part of
  a change to allow the arbitrary widgets in the title position.) The
  text can now be retrieved with the new function gtk_frame_get_text().

- The 'font' and 'font_set' declarations in RC files are now ignored. There
  is a new 'font_name' field that holds the string form of a Pango font

- A number of types in GDK have become subclasses of GObject. For the
  most part, this should not break anyone's code. However, it's now 
  possible/encouraged to use g_object_ref()/g_object_unref() and other
  GObject features with these GDK types. The converted types are:
  GdkWindow, GdkDrawable, GdkPixmap, GdkImage, GdkGC, GdkDragContext,
  GdkColormap

- All drawables including pixmaps used to have a type tag, the 
  GdkWindowType enumeration, which included GDK_WINDOW_PIXMAP.
  GdkWindowType is now a property of GdkWindow _only_, and there is
  no GDK_WINDOW_PIXMAP. You can use the GDK_IS_PIXMAP() macro to see 
  if you have a pixmap, if you need to know that.

- GtkStyle and GtkRcStyle are now subclasses of GObject as well.  This
  requires fairly extensive changes to theme engines quite badly, but
  shouldn't affect most other code.

- xthickness/ythickness have moved from GtkStyleClass to GtkStyle
  (from class to instance). This gives themes a bit more flexibility
  and is generally more of the Right Thing. You can trivially fix
  your code with s/style->klass->xthickness/style->xthickness/g and 
  same for ythickness.

- If you were using private GDK types, they have been rearranged
  significantly. You shouldn't use private types. ;-) 

- The visual for a widget, and also the default visual is now derived
  from the colormap for the widget and the default colormap. 
  gtk_widget_set_visual(), gtk_widget_set_defualt_visual(), gtk_widget_push_visual() 
  and gtk_widget_pop_visual() now do nothing. Since the visual always
  had to match that of the colormap, it is safe to simply delete
  all references to these functions.

- A number of functions in GDK have been renamed for consistency and
  clarity. #defines to provide backwards compatibility have been
  included, but can be disabled by defineing GDK_DISABLE_COMPAT_H.

  #define gdk_draw_pixmap                gdk_draw_drawable
  #define gdk_draw_bitmap                gdk_draw_drawable

  #define gdk_window_get_size            gdk_drawable_get_size
  #define gdk_window_get_type            gdk_window_get_window_type
  #define gdk_window_get_colormap        gdk_drawable_get_colormap
  #define gdk_window_set_colormap        gdk_drawable_set_colormap
  #define gdk_window_get_visual          gdk_drawable_get_visual

  #define gdk_window_ref                 gdk_drawable_ref
  #define gdk_window_unref               gdk_drawable_unref
  #define gdk_bitmap_ref                 gdk_drawable_ref
  #define gdk_bitmap_unref               gdk_drawable_unref
  #define gdk_pixmap_ref                 gdk_drawable_ref
  #define gdk_pixmap_unref               gdk_drawable_unref

  #define gdk_gc_destroy                 gdk_gc_unref
  #define gdk_image_destroy              gdk_image_unref
  #define gdk_cursor_destroy             gdk_cursor_unref

  (Note that g_object_ref() and g_object_unref() may be used for all of
  the above.)

  #define gdk_window_copy_area(drawable,gc,x,y,source_drawable,source_x,source_y,width,height) \
     gdk_draw_pixmap(drawable,gc,source_drawable,source_x,source_y,x,y,width,height)

  #define gdk_rgb_get_cmap               gdk_rgb_get_colormap

- gdk_pixmap_foreign_new() no longer calls XFreePixmap() on the 
  pixmap when the GdkPixmap is finalized. This change corresponds
  to the behavior of gdk_window_foreign_new(), and fixes a lot
  of problems with code where the pixmap wasn't supposed to be
  freed. If XFreePixmap() is needed, it can be done using the
  destroy-notification facilities of g_object_set_data().