gtk2/README

General Information
===================

This is GTK+ version 2.15.2. GTK+ is a multi-platform toolkit for
creating graphical user interfaces. Offering a complete set of widgets,
GTK+ is suitable for projects ranging from small one-off projects to
complete application suites.

GTK+ is free software and part of the GNU Project. However, the
licensing terms for GTK+, the GNU LGPL, allow it to be used by all
developers, including those developing proprietary software, without any
license fees or royalties.

The official ftp site is:
  ftp://ftp.gtk.org/pub/gtk

The official web site is:
  http://www.gtk.org/

Information about mailing lists can be found at
  http://www.gtk.org/mailinglists.html


Installation
============

See the file 'INSTALL'


Release notes for 2.14
======================

* gtkitemfactory.h is now completely deprecated.
  As gtkactiongroup.h and gtkstock.h no longer include the gtkitemfactory.h
  header, this might break application using gtk_item_factory_* symbols
  without including gtkitemfactory.h - even though this behaviour has never
  been supported in the first place.

* The GtkFileSystem semi-private interface has been removed.
  The GTK+ filechooser implementation now uses GIO directly, which has
  rendered external filesystem implementations unnecessary. Consequently,
  the GtkFileSystem interface is no longer available, nor the filechooser
  will load any GtkFileSystem implementation.

* GtkComboBox now renders the popdown button insensitive when
  the model is empty. Applications which want to populate the list
  only before displaying it can set gtk_combo_box_set_button_sensitivity
  to GTK_SENSITIVITY_ON, so that the button is always sensitive or
  GTK_SENSITIVITY_OFF to make it insensitive respectively.

* GtkAdjustment now enforces that values are restricted to the
  range [lower, upper - page_size]. This has always been the documented
  behaviour, and the recommended practice is to set page_size to 0
  when using adjustments for simple scalar values, like in a slider
  or spin button. 

* gdk-pixbuf will use GIO for mime type detection if possible. For
  this to work, shared-mime-info needs to be installed and XDG_DATA_DIRS
  set accordingly at configure time. Otherwise, gdk-pixbuf falls
  back to its built-in sniffing implementation.

Release notes for 2.12
======================

* gtk_about_dialog_get/set_name() were deprecated in favour of
  gtk_about_dialog_get/set_program_name(), the GtkAboutDialog now uses the
  "program-name" property instead of the conflicting "name" property.

* The gdk-pixbuf tiff loader now requires libtiff 3.6.0 or later.

* Support for Windows 9x/ME has officially been removed. It hasn't worked
  since 2.6 anyway.

* The GtkTextBufferTargetInfo enumeration values have been changed from
  G_MAXUINT-0, G_MAXUINT-1, G_MAXUINT-2, etc, to -1, -2, -3 to stay within
  ANSI C limits.

* A change in the handling of _NET_WM_USER_TIME properties on toplevel
  windows can cause deadlock problems with window managers that are using
  GDK for drawing decorations. In particular, metacity <= 2.18.0 is affected
  by this. The problem has been fixed in metacity 2.18.1.

* Semi-private GtkTextLayout api has changed: new GtkTextLayout method
  invalidate_cursors(), and new functions gtk_text_layout_invalidate_cursors()
  and gtk_text_layout_cursors_changed(), which should be used in place of
  gtk_text_layout_invalidate() and gtk_text_layout_changed() if invalidation
  is due to marks moved or changed selection; new GtkTextLineDisplay structure
  member. Source compatibility is preserved; binary compatibility may break
  only if GtkTextLineDisplay structure was created on stack or as a part
  of another structure (in particular GnomeCanvas and its clones do not need
  recompiling).

* Another new signal has been added to GtkNotebook. The new signal
  is called create-window, so this name can no longer be used for signals
  in objects derived from GtkNotebook.

* The gtk_notebook_set/get_group_id() functions were found to be insufficient
  and have been deprecated in favour of gtk_notebook_set/get_group().

* The move-focus signal has been moved to GtkWidget, to unify the 
  various implementations of this signal in specific widgets. Great care 
  has been taken to make sure that all code using this signal continues
  to work.

* An unused and hardly visible GtkFrame has been removed from the menu 
  widget hierarchy when GtkComboBox::appears-as-list style property is 
  set. Any RC file applying a different style to any widget below the 
  widget path "gtk-combobox-popup-window.GtkFrame" should take into 
  account that the frame no longer exists.

* The external print preview application used by GtkPrintOperationPreview 
  is now passed the print settings on the command line with the 
  --print-settings parameter pointing to a temp file containing the 
  settings. The preview application assumes ownership of the file and 
  should delete it once it does not need it anymore. The --print-settings 
  commandline option is understood by Evince 0.9.0 and newer. To use a 
  different print preview application, change the gtk-print-preview-command 
  setting in your gtkrc file, e.g. gtk-print-preview-command = "ggv %f"

* GtkMenuShell is now defined as an abstract type. It was already 
  documented as an abstract class, and there is little reason to 
  instantiate it.

* The GtkTooltips struct (this is the old tooltips API) is now considered
  private. Code that used to access this struct, in particular the
  tips_data_list field, will need to change. All of the old tooltips
  API has been deprecated in favour of a new implementation and
  API. This affects all of the gtk_tooltips_ functions, and functions 
  which take a GtkTooltips argument, such as gtk_tool_item_set_tooltip()
  and gtk_menu_tool_button_set_arrow_tooltip().
  
* The memory management of the GtkRecentManager object has been changed,
  as using the screen didn't guarantee that the singleton instance was
  correctly destroyed. The screen-related functions have been deprecated,
  and should not be used anymore; the GtkRecentManager instance returned by
  the gtk_recent_manager_get_default() function is guaranteed to be valid
  for the entire lifetime of an application.

* A number of interfaces that have been superseded by newer interfaces for 
  a long time have finally been deprecated. This includes 
  gtk_widget_ref/unref(), gtk_rc_style_ref/unref() and the old file selector.

* The various coordinate systems in use in GtkTreeView widgets have
  been clarified in the documentation, and in the cause of doing so, 
  the functions gtk_tree_view_widget_to_tree_coords() and
  gtk_tree_view_tree_to_widget_coords() have been deprecated in 
  favour of a new family of gtk_tree_view_convert_ functions.

* gtk_menu_item_remove_submenu() has been deprecated in favour of
  gtk_menu_item_set_submenu (..., NULL).

* gtk_default_draw_check() has been fixed to really decrease the
  indicator size by one pixel to ensure an odd size instead of
  accidentially increasing it.
  Consequently, gtk_cell_renderer_toggle_render() could be fixed to
  not subtract 1 from the size passed to gtk_paint_option(), which
  was just a workaround for above off-by-two for even sizes (theme
  engines now get the real indicator size passed).
  The default toggle size of GtkCheckMenuItem and GtkCellRendererToggle
  has been changed to 13 to be consistent with GtkCheckButton.
  The only visible change with default settings is that the indicator in
  GtkCellRendererToggle has changed its size from 11 to 13 and is now
  consistent with menus and toggle buttons.

* GTK+ has always required that gtk_init() (or a variant thereof) is
  called before any other GTK+ function. Some applications call functions
  like gtk_clipboard_get() to check if they need to call gtk_init(),
  anyway. A change in GLib 2.14 has recently broken this unsupported
  practise. It is worth pointing out that calling gtk_init() twice
  does no harm.


Release notes for 2.10
======================

* The hexadecimal Unicode input feature has been reworked. It no longer
  blocks the use of the sixteen Ctrl-Shift-<hex digit> key sequences. Now
  it only uses Ctrl-Shift-u.

* A memory leak in GtkStyle handling has been fixed. This may expose bugs
  in third-party widgets which forget to call gtk_style_attach() in their
  realize functions.

* Range widgets like GtkScrollbar now render their arrows insensitive
  when the slider is at the end. Applications which react to arrow
  clicks even if the slider is at the end may want to use the new
  gtk_range_set_[upper/lower]_stepper_sensitivity() functions to
  prevent the arrows from being rendered insensitive.

* GtkObject now uses the "floating reference" support in GObject. 
  GTK_OBJECT_IS_FLOATING() will still work, but direct checking
  of the GTK_FLOATING flag will no longer detect the floating 
  reference. Details about floating references can be found in the docs:
  http://developer.gnome.org/doc/API/2.0/gobject/gobject-The-Base-Object-Type.html#floating-ref

* Accelerators like (_F) are now stripped from labels when they are 
  displayed in toolbars. If this is not wanted, the feature can be 
  suppressed by inserting a Unicode control character, e.g ZWNJ.

* The pixbuf theme engine can now customize expanders (in GtkTreeView
  and GtkExpander) and resize grips, using the new EXPANDER and
  RESIZE_GRIP function values.

* Dialogs created by gtk_about_dialog_new() no longer hide automatically
  when the user clicks close. It is the applications responsibility to
  hide or destroy the dialog.

* Several new signals have been added to GtkNotebook. Care has been taken
  to choose signal names which do not collide with signals added by well-known
  derived classes. The names which can no longer be used for signals in 
  objects derived from GtkNotebook are page-reordered, page-removed and
  page-added.

* Due to the interface changes in the file chooser backend interface, 
  the GTK+ ABI version has been bumped to 2.10.0. Third-party filesystem 
  backends have to be ported to the new interface, other modules, such as 
  theme engines, input method modules or pixbuf loaders have to be rebuilt 
  so that they are installed in the right place for GTK+ to find them.


Release notes for 2.8
=====================

* GTK+ 2.8 and Pango 1.10 require the cairo library.

* The default theme has been renamed to "Raleigh". Existing configurations
  specifying the "Default" theme name should still work.

* The GtkTreeView::enable-search property has been changed to control
  only typeahead search, not the C-f keybinding to start an interactive
  search. To turn off interactive searching completely, you have to
  set GtkTreeView::search-column to -1.

* The restriction on using the same cell renderer in multiple columns
  of a GtkTreeView is now more strictly enforced.

* In GTK+ 2.8, GtkCalendar uses nl_langinfo() (if available) to determine
  the first day of the week. Thus, it is possible to select the first day
  of the week independently from the language, by setting LC_TIME.

* In GTK+ 2.8, the gtk-update-icon-cache utility includes image data
  in the icon caches, which will make the icon cache files larger than
  the one produced by GTK+ 2.6. This change will reduce the memory
  overhead of icon themes at runtime, since all GTK+ applications can
  share the image data in memory.

* In 2.8, GDK emits GdkEventGrabBroken events when a keyboard or pointer
  grab is broken. On X11, this can happen if the same application grabs
  again, or if the window used for the grab becomes unviewable. It happens
  more often on Win32. Applications which use grabs should pay attention
  to these events and do the necessary cleanups when the grab is lost.
* The GIOChannel code for sockets on win32 has been rewritten.
  Applications who make non-trivial use of GIOChannels on win32 should
  be watched for possible problems.

* GLib 2.8 uses atomic operations to implement reference counting, thus
  g_object_ref/unref, g_closure_ref/sink/unref and g_iochannel_ref/unref
  can be used without locking in multithreaded applications. Note that
  other modifications, like concurrent setting of properties still require
  locking.

* g_convert() and related character set conversion functions have been
  fixed to emit pending shift states and to not cache iconv descriptors
  across multiple calls, since that is problematic for some encodings.
  Note that these functions are not suitable for streaming conversions;
  use g_iconv() to do streaming conversion.


Release notes for 2.6
=====================

* GTK+ 2.6 supports clipboard persistency. To make use of this feature,
  a clipboard manager following the specification at
  http://www.freedesktop.org/wiki/Standards/clipboard-manager-spec
  must be running. A sample implementation of such a clipboard manager
  is available at 
  http://people.imendio.com/andersca/archives/clipboard-manager-0.3.tar.gz
  Applications can use the function gdk_display_supports_clipboard_persistence() 
  to find out if clipboard persistence is available.

* Notification on clipboard ownership changes via GdkOwnerChange events 
  requires the XFIXES X extension. Applications can use the function
  gdk_display_supports_selection_notification() to find out if ownerchip
  change notification is available.

* The icon theme code in GTK+ 2.6 follows the freedesktop.org icon theme 
  specification. Setting the XDG_DATA_DIRS environtment variable may be 
  necessary if your icons aren't installed in the default location 
  /usr/share/icons.

* The icon theme code in GTK+ 2.6 can make use of mmap()able cache files
  to avoid a lot of disk searching overhead. GTK+ includes a utility named
  gtk-update-icon-cache to generate these cache files. For further details,
  see the gtk-update-icon-cache man page or the GTK+ documentation.

* To reduce code size and improve efficiency, GTK+, when compiled 
  with the GNU toolchain, has separate internal and external entry 
  points for exported functions. The internal names, which begin with 
  IA__, may be seen when debugging a GTK+ program.

* The following functions have been deprecated in GTK+ 2.6:
  gdk_pango_context_set_colormap
  gtk_cell_renderer_editing_canceled

* The new GtkFileChooser widget emphasizes simplicity and thus does 
  not provide a navigation entry by default when opening files. 
  Experienced command line users will likely want to make heavy use of
  the location dialog brought up by the Control-L key shortcut.

* The GTK+ libraries use an '_' prefix to indicate private symbols that
  must not be used by applications. On some platforms, symbols beginning 
  with prefixes such as _gtk, _gdk, and _pango will be exported
  from the library, on others not. In no case can applications
  use these private symbols. In addition to that, GTK+ 2.6 makes several
  symbols private which were not in any installed header files and
  were never intended to be exported.

* The gdk_pixbuf_xlib library included in the contrib/ directory 
  and the framebuffer GDK backend included in the gdk/linux-fb directory
  of GTK+ are provided on an as-is basis and have not been tested at all. 
  No guarantees about the degree of workingness or about future
  compatibility are provided.

* On Unix, the assumption of GLib and GTK+ by default is that filenames on 
  the filesystem are encoded in UTF-8 rather than the encoding of the locale;
  the GTK+ developers consider that having filenames whose interpretation
  depends on the current locale is fundamentally a bad idea.

  If you have filenames encoded in the encoding of your locale, then you 
  may want to set the G_FILENAME_ENCODING environment variable:
  
   G_FILENAME_ENCODING=@locale
   export G_FILENAME_ENCODING

  (Earlier versions of GLib 2.x required a different environment variable
  setting; G_BROKEN_FILENAMES=1 to achieve the same effect; this 
  is still supported, but G_FILENAME_ENCODING is preferred.)
  Best integration of GTK+ 2.6 with the environment is achieved by 
  using a UTF-8 locale.

  On Windows, filenames passed to GTK+ should always be in UTF-8, as
  in GLib 2.6. This is different than in previous versions of GTK+
  where the system codepage was used. As in GLib, for DLL ABI
  stability, applications built against previous versions of GTK+ will
  use entry points providing the old semantics.

  When compiling against GTK+ 2.6, applications intended to be
  portable to Windows must take the UTF-8 file name encoding into
  consideration, and use the gstdio wrappers to access files whose 
  names have been constructed from strings returned from GTK+ or GLib.


How to report bugs
==================

Bugs should be reported to the GNOME bug tracking system.
(http://bugzilla.gnome.org, product gtk+.) You will need to create an
account for yourself.
  
In the bug report please include:
  
* Information about your system. For instance:

   - What operating system and version
   - What version of X
   - For Linux, what version of the C library

  And anything else you think is relevant.

* How to reproduce the bug. 

  If you can reproduce it with one of the tests or demos built with GTK+, 
  such as demos/gtk-demo/gtk-demo, that would be most convenient. Otherwise, 
  please include a short test program that exhibits the behavior. As a 
  last resort, you can also provide a pointer to a larger piece of software 
  that can be downloaded.

* If the bug was a crash, the exact text that was printed out when the
  crash occured.

* Further information such as stack traces may be useful, but is not
  necessary. If you do send a stack trace, and the error is an X error,
  it will be more useful if the stacktrace is produced running the test
  program with the --sync command line option.


Patches
=======

Patches should also be submitted to bugzilla.gnome.org. If the patch
fixes an existing bug, add the patch as an attachment to that bug
report.

Otherwise, enter a new bug report that describes the patch, and attach
the patch to that bug report.

Bug reports containing patches should include the PATCH keyword in their
keyword fields. If the patch adds to or changes the GTK+ programming
interface, the API keyword should also be included.
  
Patches should be in unified diff form. (The -u option to GNU diff.)