1:tocdepth: 2 2 3========================== 4Graphic User Interface FAQ 5========================== 6 7.. only:: html 8 9 .. contents:: 10 11.. XXX need review for Python 3. 12 13 14General GUI Questions 15===================== 16 17What platform-independent GUI toolkits exist for Python? 18======================================================== 19 20Depending on what platform(s) you are aiming at, there are several. Some 21of them haven't been ported to Python 3 yet. At least `Tkinter`_ and `Qt`_ 22are known to be Python 3-compatible. 23 24.. XXX check links 25 26Tkinter 27------- 28 29Standard builds of Python include an object-oriented interface to the Tcl/Tk 30widget set, called :ref:`tkinter <Tkinter>`. This is probably the easiest to 31install (since it comes included with most 32`binary distributions <https://www.python.org/downloads/>`_ of Python) and use. 33For more info about Tk, including pointers to the source, see the 34`Tcl/Tk home page <https://www.tcl.tk>`_. Tcl/Tk is fully portable to the 35Mac OS X, Windows, and Unix platforms. 36 37wxWidgets 38--------- 39 40wxWidgets (https://www.wxwidgets.org) is a free, portable GUI class 41library written in C++ that provides a native look and feel on a 42number of platforms, with Windows, Mac OS X, GTK, X11, all listed as 43current stable targets. Language bindings are available for a number 44of languages including Python, Perl, Ruby, etc. 45 46wxPython (http://www.wxpython.org) is the Python binding for 47wxwidgets. While it often lags slightly behind the official wxWidgets 48releases, it also offers a number of features via pure Python 49extensions that are not available in other language bindings. There 50is an active wxPython user and developer community. 51 52Both wxWidgets and wxPython are free, open source, software with 53permissive licences that allow their use in commercial products as 54well as in freeware or shareware. 55 56 57Qt 58--- 59 60There are bindings available for the Qt toolkit (using either `PyQt 61<https://riverbankcomputing.com/software/pyqt/intro>`_ or `PySide 62<https://wiki.qt.io/PySide>`_) and for KDE (`PyKDE4 <https://techbase.kde.org/Languages/Python/Using_PyKDE_4>`__). 63PyQt is currently more mature than PySide, but you must buy a PyQt license from 64`Riverbank Computing <https://www.riverbankcomputing.com/commercial/license-faq>`_ 65if you want to write proprietary applications. PySide is free for all applications. 66 67Qt 4.5 upwards is licensed under the LGPL license; also, commercial licenses 68are available from `The Qt Company <https://www.qt.io/licensing/>`_. 69 70Gtk+ 71---- 72 73The `GObject introspection bindings <https://wiki.gnome.org/Projects/PyGObject>`_ 74for Python allow you to write GTK+ 3 applications. There is also a 75`Python GTK+ 3 Tutorial <https://python-gtk-3-tutorial.readthedocs.org/en/latest/>`_. 76 77The older PyGtk bindings for the `Gtk+ 2 toolkit <http://www.gtk.org>`_ have 78been implemented by James Henstridge; see <http://www.pygtk.org>. 79 80Kivy 81---- 82 83`Kivy <https://kivy.org/>`_ is a cross-platform GUI library supporting both 84desktop operating systems (Windows, macOS, Linux) and mobile devices (Android, 85iOS). It is written in Python and Cython, and can use a range of windowing 86backends. 87 88Kivy is free and open source software distributed under the MIT license. 89 90FLTK 91---- 92 93Python bindings for `the FLTK toolkit <http://www.fltk.org>`_, a simple yet 94powerful and mature cross-platform windowing system, are available from `the 95PyFLTK project <http://pyfltk.sourceforge.net>`_. 96 97 98FOX 99---- 100 101A wrapper for `the FOX toolkit <http://www.fox-toolkit.org/>`_ called `FXpy 102<http://fxpy.sourceforge.net/>`_ is available. FOX supports both Unix variants 103and Windows. 104 105 106OpenGL 107------ 108 109For OpenGL bindings, see `PyOpenGL <http://pyopengl.sourceforge.net>`_. 110 111 112What platform-specific GUI toolkits exist for Python? 113======================================================== 114 115By installing the `PyObjc Objective-C bridge 116<https://pythonhosted.org/pyobjc/>`_, Python programs can use Mac OS X's 117Cocoa libraries. 118 119:ref:`Pythonwin <windows-faq>` by Mark Hammond includes an interface to the 120Microsoft Foundation Classes and a Python programming environment 121that's written mostly in Python using the MFC classes. 122 123 124Tkinter questions 125================= 126 127How do I freeze Tkinter applications? 128------------------------------------- 129 130Freeze is a tool to create stand-alone applications. When freezing Tkinter 131applications, the applications will not be truly stand-alone, as the application 132will still need the Tcl and Tk libraries. 133 134One solution is to ship the application with the Tcl and Tk libraries, and point 135to them at run-time using the :envvar:`TCL_LIBRARY` and :envvar:`TK_LIBRARY` 136environment variables. 137 138To get truly stand-alone applications, the Tcl scripts that form the library 139have to be integrated into the application as well. One tool supporting that is 140SAM (stand-alone modules), which is part of the Tix distribution 141(http://tix.sourceforge.net/). 142 143Build Tix with SAM enabled, perform the appropriate call to 144:c:func:`Tclsam_init`, etc. inside Python's 145:file:`Modules/tkappinit.c`, and link with libtclsam and libtksam (you 146might include the Tix libraries as well). 147 148 149Can I have Tk events handled while waiting for I/O? 150--------------------------------------------------- 151 152On platforms other than Windows, yes, and you don't even 153need threads! But you'll have to restructure your I/O 154code a bit. Tk has the equivalent of Xt's :c:func:`XtAddInput()` call, which allows you 155to register a callback function which will be called from the Tk mainloop when 156I/O is possible on a file descriptor. See :ref:`tkinter-file-handlers`. 157 158 159I can't get key bindings to work in Tkinter: why? 160------------------------------------------------- 161 162An often-heard complaint is that event handlers bound to events with the 163:meth:`bind` method don't get handled even when the appropriate key is pressed. 164 165The most common cause is that the widget to which the binding applies doesn't 166have "keyboard focus". Check out the Tk documentation for the focus command. 167Usually a widget is given the keyboard focus by clicking in it (but not for 168labels; see the takefocus option). 169