Default wallpaper

defaultwallpaper.py

#!/usr/bin/python

# https://developer.apple.com/library/mac/documentation/cocoa/reference/applicationkit/classes/NSWorkspace_Class/Reference/Reference.html
# https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSURL_Class/Reference/Reference.html
# https://developer.apple.com/library/mac/documentation/cocoa/reference/applicationkit/classes/NSScreen_Class/Reference/Reference.html

from AppKit import NSWorkspace, NSScreen
try:
    from AppKit import NSWorkspaceDesktopImageScalingKey
except ImportError:
    NSWorkspaceDesktopImageScalingKey = u'NSWorkspaceDesktopImageScalingKey'
from AppKit import NSImageScaleProportionallyUpOrDown
try:
    from AppKit import NSWorkspaceDesktopImageAllowClippingKey
except ImportError:
    NSWorkspaceDesktopImageAllowClippingKey = u'NSWorkspaceDesktopImageAllowClippingKey'
from Foundation import NSURL

picture_path = "<backgroundhere>"

# generate a fileURL
file_url = NSURL.fileURLWithPath_(picture_path)

# make image options dictionary
options = {
    NSWorkspaceDesktopImageScalingKey: NSImageScaleProportionallyUpOrDown,
    NSWorkspaceDesktopImageAllowClippingKey: True
}

# get shared workspace
ws = NSWorkspace.sharedWorkspace()

# iterate over all screens
for screen in NSScreen.screens():
    # tell the workspace to set the desktop picture
    # on 10.6 this returns 0 (failure) or 1 (success)
    # on 10.8 this returns a tuple (result, error); success is (True, None)
    result = ws.setDesktopImageURL_forScreen_options_error_(
        file_url, screen, options, None)