Goal¶

Here you will find a brief guide to use virtualenv with your wxpython project in Mac OS X.

Virtualenv has been used in the python community mostly for web projects. The idea of python isolation in virtualenv is great, but applying that to GUI development is not easy, specially when Mac OS X is your development platform.

Python 2.7 has been released and has a lot of nice features, so we are going to use it with virtualenv module and wxpython 2.8.11 in OS X ( Tiger, Leopard or Snow Leopard ).

Author¶

Domingo Aguilera ( @batok )

One time installation¶

Let’s do first of all the base installation of:

1. python 2.7 ( 32 bit ).
2. wxpython 2.8.11
3. distribute ( setuptools replacement ).
4. pip
5. virtualenv

Download and install python2.7 from python’s web site at www.python.org/download/releases/2.7/

The file that you have to download is 32-bit Mac Installer disk image ( 2.7 ) for OS X 10.3 and later.

Another way to install python 2.7 is by opening Terminal.app or iTerm.app

Change your path to where you want to download the file using the cd command.

If you have curl installed download the file typing...:

$ curl -O http://www.python.org/ftp/python/2.7/python-2.7-macosx10.3.dmg

Mount the dmg file by typing...:

$ open python-2.7-macosx10.3.dmg

Double click on the package to install it and follow the instructions.

Download and install the wxpython module available from www.wxpython.org/download.php#binaries.

Look for the link osx-unicode in the column Python2.7 of the table OS X Binaries.

Alternatively you can download the wxpython module with curl.:

$ curl -O http://downloads.sourceforge.net/wxpython/wxPython2.8-osx-unicode-2.8.11.0-universal-py2.7.dmg

Mount the dmg file by typing...:

$ open wxPython2.8-osx-unicode-2.8.11.0-universal-py2.7.dmg

Click on the package to install wxpython following the instructions.

Install distribute.

Download the tar.gz file from pypi.python.org ( search for distribute a find the link a the bottom of the page ).:

$ curl -O http://pypi.python.org/packages/source/d/distribute/distribute-0.6.14.tar.gz

$ tar zxf distribute-0.6.14.tar.gz

$ cd distribute-0.6.14

$ sudo /Library/Frameworks/Python.framework/Versions/2.7/bin/python2.7 setup.py install

Install pip in python 2.7:

$ sudo /Library/Frameworks/Python.framework/Versions/2.7/bin/easy_install pip

Install virtualenv in python 2.7:

$ sudo /Library/Frameworks/Python.framework/Versions/2.7/bin/pip install virtualenv

Create a virtualenv environment¶

$ /Library/Frameworks/Python.framework/Versions/2.7/bin/virtualenv --distribute --no-site-packages myenvfor27

$ cd myenvfor27

$ source bin/activate

Hack your environment¶

$ cd $VIRTUAL_ENV/lib/python2.7/site-packages

$ ln -s /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/wxredirect.pth wxredirect.pth

$ cd $VIRTUAL_ENV/bin

$ ln -s /Library/Frameworks/Python.framework/Versions/2.7/bin/pythonw pythonw

Now set the PYTHONPATH variable to your site-packages...:

$ cd $VIRTUAL_ENV

$ echo "export PYTHONPATH=$VIRTUAL_ENV/lib/python2.7/site-packages" > dothis

$ source dothis

Install some modules with pip in your virtual environment¶

Some examples

$ pip install sqlalchemy

$ pip install mako

$ pip install reportlab

$ pip install pyredis

Check your virtulenv modules¶

$ pip freeze

You’ll see the list of all the installed and recognized modules.

Now enter the python interpreter in your virtualenv, but the one used to run wxpython programs ( pythonw ).

>>> import sqlalchemy
>>> sqlalchemy.__version__

If the import was done the you’re done, congratulations!

Exit your interpreter as usual

>>> exit()

In anycase follow the next step to test your environment with a real program.

Test using a real GUI program¶

Copy this script to example.py in your virtual environment:

import wx
import wx.lib.agw.genericmessagedialog as GMD
import sys
try:
   import sqlalchemy
except:
   pass

def main():
   app = wx.PySimpleApp()
   try:
      version = "{}.{}".format(*list(sys.version_info[:2]))
      message = "Congratulations \nthis program uses\npython {}\nwxpython {}\nsqlalchemy {}".format(version , wx.__version__, sqlalchemy.__version__)
   except:
      message = "Sorry but you forgot to set the PYTHONPATH variable using source dothis"
   dlg = GMD.GenericMessageDialog(None, message , "A message for you", wx.OK |  ( wx.ICON_INFORMATION + GMD.GMD_USE_GRADIENTBUTTONS )  )
   dlg.ShowModal()
   dlg.Destroy()
   app.MainLoop()

if __name__ == "__main__":
   main()

And run the script:

$ pythonw example.py

If everything’s o.k. you are going to see something like this...