Changes from 1.2 to 2.0Changes from 1.2 to 2.0 — Incompatible changes made between version 1.2 and version 2.0 |
Incompatible changes from 1.2 to 2.0
The GNOME 2.0 porting guide on http://developer.gnome.org has some more detailed discussion of porting from 1.2 to 2.0. See the sections on GLib and GTK+.
GTK+ changed fairly substantially from version 1.2 to 2.0, much more so than from 1.0 to 1.2. Subsequent updates (possibilities are 2.0 to 2.2, 2.2 to 2.4, then to 3.0) will almost certainly be much, much smaller. Nonetheless, most programs written for 1.2 compile against 2.0 with few changes. The bulk of changes listed below are to obscure features or very specialized features, and compatibility interfaces exist whenever possible.
gtk_container_get_toplevels()was removed and replaced withgtk_window_list_toplevels(), which has different memory management on the return value (gtk_window_list_toplevels()copies the GList and also references each widget in the list, so you have tog_list_free()the list after first unref'ing each list member).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 forgtk_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.gtk_paned_set_handle_size()has been removed, in favor of a style property, since this is an option that only makes sense for themes to adjust.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.candgtkcolorseldialog.h.gtk_widget_shape_combine_mask()now keeps a reference count on the mask pixmap that is passed in.The GtkPatternSpec has been moved to GLib as GPatternSpec, the pattern arguments to
gtk_item_factory_dump_items()andgtk_item_factory_dump_rc()have thusly been changed to take a GPatternSpec instead of a GtkPatternSpec.-
Type system changes:
GTK_TYPE_OBJECTis 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()andGTK_TYPE_SEQNO()vanished, use ofGTK_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_preallocsgtk_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()andg_type_class_peek()is recommended over usage ofgtk_type_class(). Use ofg_type_register_static()/g_type_register_dynamic()is recommended over usage ofgtk_type_unique().
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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
klassfield anymore, an object's class can be retrieved with the object's corespondingGTK_<OBJECT>_GET_CLASS (object)macro.GtkObjectClass has no
typefield anymore, a class's type can be retrived with theGTK_CLASS_TYPE (class)macro.-
GtkObjectClass does not introduce the
finalize()andshutdown()methods anymore. Whileshutdown()is intended for GTK+ internal use only,finalize()is required by a variety of object implementations.GObjectClass.finalizeshould be overriden here, e.g.:1 2 3 4 5 6 7 8 9 10 11 12
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; }
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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:
Also, ::destroy implementations have to release object references that the object holds. Code in finalize implementations such as:
1 2 3 4 5
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. Because the ::destroy signal can be emitted multiple times, it no longer makes sense to check if a widget has been destroyed using the
GTK_OBJECT_DESTROYED()macro, and this macro has been removed. If catching destruction is still needed, it can be done with a signal connection to ::destroy. -
Signal system changes: The GTK+ 2.0 signal system merely proxies the GSignal system now. For future usage, direct use of the GSignal API is recommended, this avoids significant performance hits where GtkArg structures have to be converted into GValues. For language bindings, GSignal+GClosure provide a much more flexible and convenient mechanism to hook into signal emissions or install class default handlers, so the old GtkSignal API for language bindings is not supported anymore.
Functions that got removed in the GTK+ signal API:
gtk_signal_n_emissions(),gtk_signal_n_emissions_by_name(),gtk_signal_set_funcs(),gtk_signal_handler_pending_by_id(),gtk_signal_add_emission_hook(),gtk_signal_add_emission_hook_full(),gtk_signal_remove_emission_hook(),gtk_signal_query(). Also, the GtkCallbackMarshal argument togtk_signal_connect_full()is not supported anymore. For many of the removed functions, similar variants are available in theg_signal_*namespace. The GSignal system performs emissions in a slightly different manner than the old GtkSignal code. Signal handlers that are connected to signal "foo" on object "bar" while "foo" is being emitted, will not be called anymore during the emission they were connected within. 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
labelfield of GtkFrame widgets has been removed (as part of a change to allow arbitrary widgets in the title position). The text can now be retrieved with the new functiongtk_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 noGDK_WINDOW_PIXMAP. You can use theGDK_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, but shouldn't affect most other code.
xthicknessandythicknesshave 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 withs/style->klass->xthickness/style->xthickness/gand same forythickness.Some GtkStyle
draw_*methods have been removed (cross, oval, ramp) and others have been added (expander, layout). This will require changes to theme engines.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_default_visual(),gtk_widget_push_visual()andgtk_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 defining
GDK_DISABLE_DEPRECATED.Old function Defined As gdk_draw_pixmapgdk_draw_drawablegdk_draw_bitmapgdk_draw_drawablegdk_window_get_sizegdk_drawable_get_sizegdk_window_get_typegdk_window_get_window_typegdk_window_get_colormapgdk_drawable_get_colormapgdk_window_set_colormapgdk_drawable_set_colormapgdk_window_get_visualgdk_drawable_get_visualgdk_window_refgdk_drawable_refgdk_window_unrefgdk_drawable_unrefgdk_bitmap_refgdk_drawable_refgdk_bitmap_unrefgdk_drawable_unrefgdk_pixmap_refgdk_drawable_refgdk_pixmap_unrefgdk_drawable_unrefgdk_gc_destroygdk_gc_unrefgdk_image_destroygdk_image_unrefgdk_cursor_destroygdk_cursor_unrefgdk_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)gdk_rgb_get_cmapgdk_rgb_get_colormap(Note that
g_object_ref()andg_object_unref()may be used for all of the above ref and unref functions.)gtk_widget_popup()was removed, it was only usable for GtkWindows, and there the same effect can be achieved bygtk_window_move()andgtk_widget_show(). gdk_pixmap_foreign_new()no longer callsXFreePixmap()on the pixmap when the GdkPixmap is finalized. This change corresponds to the behavior ofgdk_window_foreign_new(), and fixes a lot of problems with code where the pixmap wasn't supposed to be freed. IfXFreePixmap()is needed, it can be done using the destroy-notification facilities ofg_object_set_data().-
GtkProgress/GtkProgressBar had serious problems in GTK+ 1.2.
Only 3 or 4 functions are really needed for 95% of progress interfaces; GtkProgress/GtkProgressBar had about 25 functions, and didn't even include these 3 or 4.
In activity mode, the API involves setting the adjustment to any random value, just to have the side effect of calling the progress bar update function - the adjustment is totally ignored in activity mode.
You set the activity step as a pixel value, which means to set the activity step you basically need to connect to size_allocate.
There are
ctree_set_expander_style()-functions, to randomly change look-and-feel for no good reason.The split between GtkProgress and GtkProgressBar makes no sense to me whatsoever.
This was a big wart on GTK+ and made people waste lots of time, both learning and using the interface. So, we have added what we feel is the correct API, and marked all the rest deprecated. However, the changes are 100% backward-compatible and should break no existing code. The following 5 functions are the new programming interface and you should consider changing your code to use them:
void gtk_progress_bar_pulse (GtkProgressBar *pbar); void gtk_progress_bar_set_text (GtkProgressBar *pbar, const gchar *text); void gtk_progress_bar_set_fraction (GtkProgressBar *pbar, gfloat fraction); void gtk_progress_bar_set_pulse_step (GtkProgressBar *pbar, gfloat fraction); void gtk_progress_bar_set_orientation (GtkProgressBar *pbar, GtkProgressBarOrientation orientation); The GtkNotebookPage structure has been removed from the public header files; this was never meant to be a public structure, and all functionality that could be done by accessing the struct fields of this structure should be accessible otherwise.
Negative values of the
positionparameter togtk_notebook_reorder_child()now cause the page to be appended, not inserted at the beginning. (This gives consistency withgtk_box_reorder_child(),gtk_menu_reorder_child().)-
GtkMenuPositionFunchas a new parameterpush_inwhich controls how menus placed outside the screen is handled. If this is set toTRUEand part of the menu is outside the screen then GTK+ pushes it into the visible area. Otherwise the menu is cut of at the end of the visible screen area.Regardless of what happens to the size of the menu, the result is always that the items are placed in the same place as if the menu was placed outside the screen, using menu scrolling if necessary.
The "draw" signal and virtual method on GtkWidget has been removed. All drawing should now occur by invalidating a region of the widget (call
gdk_window_invalidate_rect()orgtk_widget_queue_draw()for example to invalidate a region). GTK+ merges all invalid regions, and sends expose events to the widget in an idle handler for the invalid regions.gtk_widget_draw()is deprecated but still works; it adds the passed-in area to the invalid region and immediately sends expose events for the current invalid region. Most widgets will work fine if you just delete their "draw" implementation, since they will already have working expose_event implementations. The draw method was rarely called in practice anyway.The GdkExposeEvent has a new
regionfield. This can be used instead of theareafield if you want a more exact representation of the area to update.Sending synthetic exposes using
gtk_widget_event()is no longer allowed. If you just need an expose call you should usegdk_window_invalidate_rect()orgdk_window_invalidate_region()instead. For the case of container widgets that need to propagate expose events toNO_WINDOWchildren you can either usegtk_container_propagate_expose(), or chain to the default container expose handler.The draw_default and draw_focus methods/signals on GtkWidget are gone; simply draw things in your expose handler.
gtk_widget_draw_focus()andgtk_widget_draw_default()wrapper functions are also gone; just queue a draw on the widget, or the part affected by the focus/default anyway. Also, GtkWidget now has default implementations for focus_in_event and focus_out_event. These set/unsetGTK_HAS_FOCUS, and queue a draw. So if your focus in/out handler just does that, you can delete it.GtkText and GtkTree are buggy and broken. We don't recommend using them, and changing old code to avoid them is a good idea. The recommended alternatives are GtkTextView and GtkTreeView. The broken widgets are not declared in the headers by default; to use them, define the symbol
GTK_ENABLE_BROKENduring compilation. In some future release, these widgets will be removed from GTK+.GdkColorContext is gone; you probably weren't using it anyway. Use GdkColormap and the
gdk_rgb_*functions instead.GtkMenuBar now draws the
GtkContainer::border_widthspace outside the frame, not inside the frame.In GTK+ 1.2, if an event handler returned
TRUEit prevented propagation of that event to parent widgets. That is, the event signal would not be emitted on parent widgets. In GTK+ 2.0, if an event handler returnsTRUE, the current signal emission on the current widget is immediately stopped. That is, other callbacks connected to the signal will not be invoked.-
gtk_toolbar_new()no longer has arguments. This function was broken because the defaultGtkToolbarStyle(icons, text, both) is now a user preference, which is overridden when you callgtk_toolbar_set_style(). The constructor forced everyone to override the preference, which was undesirable. So to port your app, decide if you want to force the toolbar style or conform to the user's global defaults; if you want to force it, callgtk_toolbar_set_style().The orientation arg was removed from
gtk_toolbar_new()as well, just because it wasn't very useful and we were breaking the function anyway so had an opportunity to lose it. Callgtk_toolbar_set_orientation()to set toolbar orientation. -
GtkRange/GtkScrollbar/GtkScale were rewritten; this means that most theme engines won't draw them properly, and any custom subclasses of these widgets will need a rewrite (though if you could figure out how to subclass the old version of GtkRange, you have our respect). Also,
GtkTroughTypeis gone.Here are some notable changes:
stepper_sizestyle property is the height for vertical ranges, width for horizontal; the other dimension matches the trough size.Added the ability to do NeXT-style steppers (and several other styles that don't make any sense).
Added
min_slider_length,fixed_slider_lengthproperties to GtkScrollbar.Cleaned some private (or at least useless) functions out of
gtkscale.h, e.g.gtk_scale_value_width.Moved bindings from subclasses to GtkScale, even arrow keys, since blind users don't know scale orientation.
Changed
move_slideraction signal to use new GtkScrollType, remove GtkTroughType argument.Digits rounds the values a range will input to the given number of decimals, but will not try to force adjustment values set by other controllers. That is, we no longer modify
adjustment->valueinside avalue_changedhandler.Added getters for GtkScale setters.
Middle-click begins a slider drag.
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The GtkContainer::focus signal/virtual function and
gtk_container_focus()call were replaced by GtkWidget::focus andgtk_widget_child_focus(). The semantics are the same, so you should be able to just replacecontainer_class->focus = mywidget_focuswithwidget_class->focus = mywidget_focusand replacegtk_container_focus()calls withgtk_widget_child_focus()calls.The purpose of this change was to allow non-containers to have focusable elements.
gtk_rc_set_image_loader()andgtk_rc_load_image()have been removed, now that GTK+ includes decent image loading capabilities itself.An extra GtkSettings argument has been added to
gtk_rc_find_pixmap_in_path(). This function is only actually useful from a theme engine during parsing, at which point the GtkSettings is provided.The child argument facility in
gtkcontainer.chas been converted to a child property facility using GParamSpec and other facilities for GObject.The
set_child_arg()andget_child_arg()virtual methods have been replaced withset_child_property()/get_child_property(), which work similar to GObject->set_property/get_property.-
Other removed GtkContainer functions with the replacements:
Old function Replacement gtk_container_add_child_arg_typegtk_container_class_install_child_propertygtk_container_query_child_argsgtk_container_class_list_child_propertiesgtk_container_child_getvgtk_container_child_set_propertygtk_container_child_setvgtk_container_child_get_propertygtk_container_add_with_argsgtk_container_add_with_propertiesgtk_container_addvgtk_container_add/gtk_container_child_set_property gdk_image_get()(or rather its replacement,gdk_drawable_get_image()) now handles errors properly by returningNULL, previously it would crash. Also, a window being offscreen is no longer considered an error; instead, the area contains undefined contents for the offscreen areas. In most cases, code usinggdk_image_get()should really be ported togdk_pixbuf_get_from_drawable().gtk_widget_set_usize()has been renamed togtk_widget_set_size_request(), however the old name still exists unless you defineGTK_DISABLE_DEPRECATED.gtk_widget_set_uposition()is deprecated; usegtk_window_move(),gtk_fixed_put(), orgtk_layout_put()instead.gtk_window_set_policy()is deprecated. To get the effect of "allow_shrink", callgtk_widget_set_size_request (window, 0, 0). To get the effect of "allow_grow", callgtk_window_set_resizable (window, TRUE). You didn't want the effect of "auto_shrink", it made no sense. But maybe if you were using it you want to usegtk_window_resize (window, 1, 1)to snap a window back to its minimum size (the 1, 1 will be rounded up to the minimum window size).The core GTK+ now takes care of handling mapping, unmapping and realizing the child widgets of containers in
gtk_widget_set_parent(). In most cases, this allows container implementations to be simplified by removing the code inadd()methods to map and realize children. However, there are a couple of things to watch out for here:If the parent is realized before the
add()happens,gtk_widget_set_parent_window()must be called beforegtk_widget_set_parent(), sincegtk_widget_set_parent()will realize the child.-
If a container depended on its children not being mapped unless it did so itself (for example, GtkNotebook only mapped the current page), then the new function
gtk_widget_set_child_visible()must be called to keep widgets that should not be mapped not mapped.As part of this change, most containers also will no longer need custom implementations of the
map()andunmap()virtual functions. The only cases where this is necessary are:For
!NO_WINDOWwidgets, if you create children ofwidget->windowand don't map them inrealize()then you must map them inmap(). [ In almost all cases, you can simply map the windows inrealize(). ]For
NO_WINDOWwidgets, if you create windows in yourrealize()method, you must map then inmap()and unmap them inunmap().
gtk_widget_set_default_style(),gtk_widget_push_style(), andgtk_widget_pop_style()have been removed, since they did not work properly with themes and there were better alternatives for modifying the appearance of widgets. You should generally usegtk_widget_modify_*()instead.gtk_image_new()now takes no arguments and creates an empty GtkImage widget. To create a GtkImage widget from a GdkImage (the least common usage of GdkImage), usegtk_image_new_from_image().GTK_SELECTION_EXTENDEDis now deprecated, and neither the GtkList/GtkTree nor the GtkCList/GtkCTree supportGTK_SELECTION_EXTENDEDanymore. However, the old extended behavior replacesMULTIPLEbehavior.-
The following variables are no longer exported from GDK. (Other variables are also no longer exported; the following are the ones found used externally in a large sample of GTK+ code.)
Variable Replacement gdk_null_window_warningsNone - did nothing in GTK+ 1.2 gdk_leader_windowNone - private variable gdk_screengdk_x11_get_default_screen ()gdk_root_windowgdk_x11_get_default_root_xwindow ()gdk_root_parentgdk_get_default_root_window ()gdk_error_codegdk_error_trap_push ()/pop ()gdk_error_warningsgdk_error_trap_push ()/pop ()gdk_display_namegdk_get_display ()gdk_wm_delete_windowgdk_atom_intern ("WM_DELETE_WINDOW", FALSE)gdk_wm_take_focusgdk_atom_intern ("WM_TAKE_FOCUS", FALSE)gdk_wm_protocolsgdk_atom_intern ("WM_PROTOCOLS", FALSE) -
The handling of colormaps and widgets has been changed:
The default colormap for widgets is now the GdkRGB colormap, not the system default colormap. If you try to use resources created for a widget (e.g.,
widget->style) with a window using the system colormap, errors will result on some machines.gtk_widget_push()/gtk_widget_pop_colormap()only cause the colormap to be explicitly set on toplevel widgets, not on all widgets. The colormap for other widgets (when not set usinggtk_widget_set_colormap()), is determined by finding the nearest ancestor with a colormap set on it explicitly, or if that fails, the default colormap.
The default selected day for GtkCalendar is now the current day in the month, not the first day in the month. The current month and year were already used.
GDK is no longer put into threaded mode automatically when
g_thread_init()has been called. In order to use the global GDK thread mutex withgdk_threads_enter()andgdk_threads_leave(), you must callgdk_threads_init()explicitly. If you aren't using GDK and GTK+ functions from multiple threads, there is no reason to callgdk_threads_init().The GtkPreviewInfo struct has had its visual and colormap fields removed. Also,
gtk_preview_get_cmap()andgtk_preview_get_visual()are deprecated, as GdkRGB works on any colormap and visual. You no longer need togtk_widget_push_cmap (gtk_preview_get_cmap ())in your code.The GtkBox, GtkTable, and GtkAlignment widgets now call
gtk_widget_set_redraw_on_allocate (widget, FALSE);on themselves. If you want to actually draw contents in a widget derived from one of these widgets, you'll probably want to change this in yourinit()function.-
A number of widgets are now
NO_WINDOWwidgets (most importantly GtkButton, but also GtkRange and GtkNotebook) This has a couple of effects:If you are deriving from one of these widgets, you need to adapt your code appropriately -- for instance, drawing coordinates start from
widget->allocation.x, widget->allocation.y.If you are embedding one of these widgets in a custom widget, you must make sure you call
gtk_container_propagate_expose()correctly, as you must for anyNO_WINDOWwidgets.
GtkFixed is a little special; it is now created by default as a
NO_WINDOWwidget, but if you dogtk_fixed_set_has_window (fixed, TRUE);after creating a fixed widget, it will create a window and handle it properly.
GtkLayout no longer has the
xoffset,yoffsetfields, which used to store the difference between world and window coordinates forlayout->bin_window. These coordinate systems are now always the same.-
gtk_paint_focus(),gtk_draw_focus()andGtkStyle::draw_focus()have been changed a bit:A
GtkStateTypeargument has been added togtk_paint_focus().The default implementation of the
GtkStyle::draw_focus()virtual function now draws a focus rectangle whose width is determined by the GtkWidget::focus-width style property.The rectangle passed in is the bounding box, instead of the rectangle used in the
gdk_draw_rectangle()call, so it is no longer necessary to subtract 1 from the width and height.
