# Based on this file: # https://github.com/pallets/werkzeug/blob/master/werkzeug/_reloader.py import time, os, sys, subprocess PY2 = sys.version_info[0] == 2 class Reloader(object): RELOADING_CODE = 3 def start_process(self): """Spawn a new Python interpreter with the same arguments as this one, but running the reloader thread. """ while True: print("starting Tkinter application...") args = [sys.executable] + sys.argv env = os.environ.copy() env['TKINTER_MAIN'] = 'true' # a weird bug on windows. sometimes unicode strings end up in the # environment and subprocess.call does not like this, encode them # to latin1 and continue. if os.name == 'nt' and PY2: for key, value in env.iteritems(): if isinstance(value, unicode): env[key] = value.encode('iso-8859-1') exit_code = subprocess.call(args, env=env, close_fds=False) if exit_code != self.RELOADING_CODE: return exit_code def trigger_reload(self): self.log_reload() sys.exit(self.RELOADING_CODE) def log_reload(self): print("reloading...") def run_with_reloader(root, *hotkeys): """Run the given application in an independent python interpreter.""" import signal signal.signal(signal.SIGTERM, lambda *args: sys.exit(0)) reloader = Reloader() try: if os.environ.get('TKINTER_MAIN') == 'true': for hotkey in hotkeys: root.bind_all(hotkey, lambda event: reloader.trigger_reload()) if os.name == 'nt': root.wm_state("iconic") root.wm_state("zoomed") root.mainloop() else: sys.exit(reloader.start_process()) except KeyboardInterrupt: pass if __name__ == "__main__": from tkinter import Tk, Label class App(Tk): def __init__(self): Tk.__init__(self) Label(self, text="Press Control+r to reload...").pack() run_with_reloader(App(), "", "")