Activate window by process ID in Python

window_activation.py

# ref: https://sjohannes.wordpress.com/tag/win32/

from __future__ import print_function
import ctypes
from ctypes import windll
import sys

Win32 = windll.user32
EnumWindowsProc = ctypes.WINFUNCTYPE(ctypes.c_int, ctypes.POINTER(ctypes.c_int), ctypes.POINTER(ctypes.c_int))

def activate_window_by_pid(pid):
    def activate_window(hwnd):
        target_pid = ctypes.c_ulong()
        Win32.GetWindowThreadProcessId(hwnd, ctypes.byref(target_pid))
        if pid == target_pid.value:
            Win32.SetForegroundWindow(hwnd)
            Win32.BringWindowToTop(hwnd)
            return True
        else:
            return False

    def each_window(hwnd, _):
        if activate_window(hwnd):
            print("Activate: {0}".format(pid))
        return 1

    proc = EnumWindowsProc(each_window)
    Win32.EnumWindows(proc, 0)

def main():
    target_pids = [int(arg) for arg in sys.argv[1:]]
    for pid in target_pids:
        activate_window_by_pid(pid)

if __name__ == "__main__":
    main()