Background color of tkinter label will not change (python 3.4)

Question

I am making a widget with Tkinter in python 3.4. For some reason, I cannot change a label's background color from the default grey. The code for the label is something like this:

self.label = ttk.Label(master, text="Label Text", 
                       foreground="blue", background="yellow")

Everything else works fine. I can change the foreground (text) color, however the background will not change, whether I am using label.config(), label['background'], or whatever.

I can change the background if I write it for Python 2.7, but I am using tutorials for Tkinter in 3.4, so this is undesirable.

Answer 1

This bug is caused by the 'aqua' ttk style on Mac OSX. It also breaks 'ttk.Progressbar' when set to 'indeterminate' mode. To fix both issues insert the following code after 'root = Tk()' to change the style ...

style = ttk.Style()
style.theme_use('classic') # Any style other than aqua.

This solution was posted by dietrich41 here : http://www.python-forum.org/viewtopic.php?f=12&t=16212

I tested it on a Mac running Python 3.4.1.