external_screen.py

   1 #!/usr/bin/python
   2 import sys, re, subprocess
   3 from PyQt4 import QtGui
   4 from selector_window import PositionSelection
   5 app = QtGui.QApplication(sys.argv)
   6
   7 def getXrandrInformation():
   8         p = subprocess.Popen(["xrandr", "-q"], stdout=subprocess.PIPE)
   9         connectors = {} # map of connector names to a list of resolutions
  10         connector = None # current connector
  11         for line in p.stdout:
  12                 # new connector?
  13                 m = re.search(r'^([\w]+) connected ', line)
  14                 if m is not None:
  15                         connector = m.groups()[0]
  16                         assert connector not in connectors
  17                         connectors[connector] = []
  18                         continue
  19                 # new resolution?
  20                 m = re.search(r'^   ([\d]+)x([\d]+) +', line)
  21                 if m is not None:
  22                         assert connector is not None
  23                         connectors[connector].append((int(m.groups()[0]), int(m.groups()[1])))
  24         p.communicate()
  25         if p.returncode != 0: raise Exception("Querying xrandr for data failed")
  26         return connectors
  27
  28 def res2str(res):
  29         (w, h) = res
  30         return str(w)+'x'+str(h)
  31
  32 # Check screen setup
  33 internalName = "LVDS"
  34 externalName = "CRT1"
  35 connectors = getXrandrInformation()
  36 internalResolutions = connectors[internalName] # there must be a screen assoicated to the internal connector
  37 externalResolutions = connectors.get(externalName)
  38
  39 # Check what to do
  40 internalArgs = ["--mode", res2str(internalResolutions[0])] # there must be a resolution for the internal screen
  41 externalArgs = ["--off"]
  42 if externalResolutions is not None: # we need to ask what to do
  43         extPosition = PositionSelection(map(res2str, externalResolutions))
  44         extPosition.exec_()
  45         if not extPosition.result(): sys.exit(1) # the user canceled
  46         # build command-line
  47         externalArgs = ["--mode", extPosition.resolution] # we definitely want an external screen
  48         if extPosition.position == PositionSelection.EXTERNAL_ONLY:
  49                 internalArgs = ["--off"]
  50         elif extPosition.position == PositionSelection.LEFT:
  51                 externalArgs += ["--left-of", internalName]
  52         else:
  53                 externalArgs += ["--right-of", internalName]
  54 # and do it
  55 call = ["xrandr", "--output", internalName] + internalArgs + ["--output", externalName] + externalArgs
  56 print "Call that will be made:",call
  57 subprocess.check_call(call)