diff --git a/IPython/lib/guisupport.py b/IPython/lib/guisupport.py new file mode 100644 index 0000000..9a0503d --- /dev/null +++ b/IPython/lib/guisupport.py @@ -0,0 +1,140 @@ +#!/usr/bin/env python +# coding: utf-8 +""" +Support for creating GUI apps and starting event loops. + +IPython's GUI integration allows interative plotting and GUI usage in IPython +session. IPython has two different types of GUI integration: + +1. The terminal based IPython supports GUI event loops through Python's + PyOS_InputHook. PyOS_InputHook is a hook that Python calls periodically + whenever raw_input is waiting for a user to type code. We implement GUI + support in the terminal by setting PyOS_InputHook to a function that + iterates the event loop for a short while. It is important to note that + in this situation, the real GUI event loop is NOT run in the normal + manner, so you can't use the normal means to detect that it is running. +2. In the two process IPython kernel/frontend, the GUI event loop is run in + the kernel. In this case, the event loop is run in the normal manner by + calling the function or method of the GUI toolkit that starts the event + loop. + +In addition to starting the GUI event loops in one of these two ways, IPython +will *always* create an appropriate GUI application object when GUi +integration is enabled. + +If you want your GUI apps to run in IPython you need to do two things: + +1. Test to see if there is already an existing main application object. If + there is, you should use it. If there is not an existing application object + you should create one. +2. Test to see if the GUI event loop is running. If it is, you should not + start it. If the event loop is not running you may start it. + +This module contains functions for each toolkit that perform these things +in a consistent manner. Because of how PyOS_InputHook runs the event loop +you cannot detect if the event loop is running using the traditional calls +(such as ``wx.GetApp.IsMainLoopRunning()`` in wxPython). If PyOS_InputHook is +set These methods will return a false negative. That is, they will say the +event loop is not running, when is actually is. To work around this limitation +we proposed the following informal protocol: + +* Whenever someone starts the event loop, they *must* set the ``_in_event_loop`` + attribute of the main application object to ``True``. This should be done + regardless of how the event loop is actually run. +* Whenever someone stops the event loop, they *must* set the ``_in_event_loop`` + attribute of the main application object to ``False``. +* If you want to see if the event loop is running, you *must* use ``hasattr`` + to see if ``_in_event_loop`` attribute has been set. If it is set, you + *must* use its value. If it has not been set, you can query the toolkit + in the normal manner. + +The functions below implement this logic for each GUI toolkit. If you need +to create custom application subclasses, you will likely have to modify this +code for your own purposes. This code can be copied into your own project +so you don't have to depend on IPython. + +""" + +#----------------------------------------------------------------------------- +# Copyright (C) 2008-2010 The IPython Development Team +# +# Distributed under the terms of the BSD License. The full license is in +# the file COPYING, distributed as part of this software. +#----------------------------------------------------------------------------- + +#----------------------------------------------------------------------------- +# Imports +#----------------------------------------------------------------------------- + +#----------------------------------------------------------------------------- +# wx +#----------------------------------------------------------------------------- + +def get_app_wx(*args, **kwargs): + """Create a new wx app or return an exiting one.""" + import wx + app = wx.GetApp() + if app is None: + app = wx.PySimpleApp(*args, **kwargs) + return app + +def is_event_loop_running_wx(app=None): + """Is the wx event loop running.""" + if app is None: + app = get_app_wx() + if hasattr(app, '_in_event_loop'): + return app._in_event_loop + else: + return app.IsMainLoopRunning() + +def start_event_loop_wx(app=None): + """Start the wx event loop in a consistent manner.""" + if app is None: + app = get_app_wx() + if not is_event_loop_running_wx(app): + app._in_event_loop = True + app.MainLoop() + app._in_event_loop = False + else: + app._in_event_loop = True + +#----------------------------------------------------------------------------- +# qt4 +#----------------------------------------------------------------------------- + +def get_app_qt4(*args, **kwargs): + """Create a new qt4 app or return an existing one.""" + from PyQt4 import QtGui + app = QtGui.QApplication.instance() + if app is None: + app = QtGui.QApplication(*args, **kwargs) + return app + +def is_event_loop_running_qt4(app=None): + """Is the qt4 event loop running.""" + if app is None: + app = get_app_qt4() + if hasattr(app, '_in_event_loop'): + return app._in_event_loop + else: + # Does qt4 provide a other way to detect this? + return False + +def start_event_loop_qt4(app=None): + """Start the qt4 event loop in a consistent manner.""" + if app is None: + app = get_app_qt4() + if not is_event_loop_running_qt4(app): + app._in_event_loop = True + app.exec_() + app._in_event_loop = False + else: + app._in_event_loop = True + +#----------------------------------------------------------------------------- +# Tk +#----------------------------------------------------------------------------- + +#----------------------------------------------------------------------------- +# gtk +#-----------------------------------------------------------------------------