Where has this been tested? We should have someone (even if not yourself) test this for Tk, Gtk, Gtk3 and Wx under Linux, Windows and OS-X.

Test matrix (I will update with people once they can confirm working):

Test process:

import matplotlib
# set the appropriate backend for your test
matplotlib.use('TkAgg')
matplotlib.use('GTKAgg')
matplotlib.use('GTK3Agg')
matplotlib.use('WXAgg')

import matplotlib.pyplot as plt
plt.plot(range(10))
plt.show()

Check the icon displays in the toolbar & in the title bar.

Thanks. The .gif file is still not getting installed. You need to add a line for mpl-data/images/*.gif to the package_data list in setup.py.

Tested (successfully) all backends on Linux.

On OS X, under ipython, with TkAgg, I get

TclError: can't use "pyimage1" as iconphoto: not a photo image

from the line

---> 89         window.tk.call('wm', 'iconphoto', window._w, icon_img)

In pdb it does look like icon_img is a PhotoImage:

ipdb> window.tk
<tkapp object at 0x103ff1370>
ipdb> window._w
'.'
ipdb> icon_img
<Tkinter.PhotoImage instance at 0x103ff4e60>

Thanks @jkseppan. I've put a try except around that line to catch the failure on some OSes.
By the way, which backends were you able to test on?

OS X 10.6.8, Python 2.7.3 via MacPorts:

TkAgg: crashes (probably unrelated to this change)
GtkAgg: shows the X11 logo as the icon
Gtk3Agg: couldn't install pygobject
Qt4Agg: shows a yellow sine wave as the title bar icon, a box with "exec" when you press Cmd+Tab and in the dock (this is usual when you run a binary that opens a window but is not a proper application)

Trying again, OS X 10.6.8, Python 2.7.3 via Homebrew:

GtkAgg: shows the X11 logo in the window title bar

backend GTKAgg version 2.24.0
Could not load matplotlib icon: Couldn't recognize the image file format for file '/opt/homebrew/Cellar/python/2.7.3/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib-1.2.x-py2.7-macosx-10.6-x86_64.egg/matplotlib/mpl-data/images/matplotlib.svg'

OSX, TkAgg, WxAgg: nothing in the title bar

Qt4Agg: sine wave in the title bar

The icon shown in the Dock and when you press Cmd-Tab is the Python starship icon, except with GtkAgg it's the X11 icon (which is what OS X always shows for X11.app).

Actually I'm not sure if title bar icons are the right thing on OS X. Apple's user interface guidelines says title bars can have what they call a proxy icon "after the user has given a document a name and save location for the first time", and users can drag-and-drop the icon to e.g. attach the document in an email, or cmd-click the icon to navigate the file system hierarchy up from the save location. I don't think a matplotlib plot window is a document like that - it's an interactive view into the object, and you can save a png or pdf representation of the plot, but you can't save the program state that corresponds to what's visible in the window.

One thing that would be nice is a matplotlib icon for the Dock and Cmd-Tab, but I think that's a different task altogether.

Thanks @jkseppan. I didn't get that warning for GtkAgg backend (gtk 2.24 installed via homebrew on osx 10.7).

Out of interest, did you get Gtk3 and wx from homebrew? I haven't been as successful with those dependencies.

Other than perhaps addressing the warning (which I am unable to reproduce), I don't see any blockers on this, any objections?

Sorry, I didn't mean that Gtk3 prints a warning - I meant that I couldn't install Gtk3Agg at all, because I can't find a way to install pygobject via homebrew (or MacPorts). I found someone's homebrew branch with an attempt, but it had diverged so far from mainstream homebrew that I feared it would break my Gtk3 installation. There's some information about the problems at https://trac.macports.org/ticket/33877 (basically you have to build various dependencies with --enable-introspection, but both MacPorts and Homebrew use --disable-introspection on everything, because introspection breaks something else).

I installed wxpython via brew install wxmac --python --devel and it seems to work fine.

@jkseppan: It appears you are the only one who has seen any issues with this, is there any action that needs to be done? or are we at a stage where you would be happy to merge?

I'm happy with merging this. It just doesn't show the icon on my system with GtkAgg, but it's no worse than before.

@jkseppan I've rebased. Would you mind doing the merge?

Merging...