#!/usr/bin/env python3

# Cycle between connected monitors using xrandr.

# For instance, bind this to XF86Display in your window manager.

import sys

import subprocess

# Use monmon to detect connected and active monitors using python-xrandr.

# This saves needing to call xrandr and xrandr --listactivemonitors separately,

# which took twice as long.

import monmon

DEBUGFILE = open("/tmp/moncycle", "a")

print("==== moncycle ===============", file=DEBUGFILE)

monmon = monmon.MonMon()

monmon.find_monitors()

# Monitors that are physically connected (a dict of dicts):

connected_mons = monmon.connected_monitors()

# If there are no connected monitors, big trouble.

if not connected_mons:

print("No monitors connected! Bailing.", file=DEBUGFILE)

sys.exit(1)

print("Connected monitors:", connected_mons, file=DEBUGFILE)

# If only one monitor is connected, no-brainer.

if len(connected_mons) == 1:

print("Only one connected monitor", file=DEBUGFILE)

args = ["xrandr", "--output", connected_mons[0], "--auto"]

print("calling", args, file=DEBUGFILE)

subprocess.call(args)

sys.exit(0)

# All monitors that are currently active:

active_mons = monmon.active_monitors()

if active_mons:

# First monitors that's currently active

active_mon = active_mons[0]

print("Active monitors:", active_mons, file=DEBUGFILE)

else:

active_mon = None

print("No active monitors", file=DEBUGFILE)

# Nothing active? Use the first connected monitor.

nextindex = 0

# See if anything is active:

for i, mon in enumerate(connected_mons):

if mon == active_mon:

nextindex = (i+1) % len(connected_mons)

break

args = [ "xrandr" ]

for i, mon in enumerate(connected_mons):

if i == nextindex:

args += [ "--output", mon, "--auto" ]

else:

args += [ "--output", mon, "--off" ]

print("Calling:", args, file=DEBUGFILE)

subprocess.call(args)