curses wrapper in multithread does not restore screen after quiting - python-3.x

Question

I'm trying to develop a multithreaded program with a TUI interface . Basically I have a main Loop deciding what to do and some task (like the TUI or reading data from a queue and processing it ) are running in separate thread .
My TUI is using curses and is a thread derived class that look like this (i removed non essential code for clarity) :
import threading
from time import sleep
import curses
import logging
from curses.textpad import Textbox, rectangle
from datetime import datetime
import re
from curses import panel
import os
import sys
class GenericTUI(threading.Thread):
def __init__(self, logger=logging.getLogger()):
threading.Thread.__init__(self,name="genericTUI" + str(os.getpid()), daemon=True)
self.keyPressedList = list()
self.alive = True
self._myStdscr = None
self.title = ""
self.logger = logger
self.lock = threading.Lock()
def run(self):
curses.wrapper(self.main)
curses.nocbreak()
curses.echo()
curses.noraw()
sys.exit(0)
def main(self,stdscr):
self._myStdscr = stdscr
self._myStdscr.nodelay(True)
self._myStdscr.keypad(True)
self._myStdscr.box()
while self.alive:
sleep(0.4)
try :
key = self._myStdscr.getkey()
if re.match('[A-Z_\+\-\*/]', key):
self.keyPressedList.append(key)
except Exception as e:
## ignoring no key presssed
pass
try :
with self.lock :
self._myStdscr.clear()
self._myStdscr.addstr(1, 2, str(datetime.now())+" "+ sys.argv[0] +" "+self.title )
### printing other things
self._myStdscr.refresh()
except Exception as e:
self.logger.error(e, exc_info=True)
continue
self._myStdscr.clear()
self._myStdscr.keypad(0)
def getKeyPressed(self):
if self.keyPressedList :
return self.keyPressedList.pop()
else :
return None
def stop(self):
self.alive = False
def updateTitle(self,title):
with self.lock : self.title = title
if __name__ == "__main__":
## the main is used for some test when the lib is called directly
testGUI = GenericTUI()
alive = True
testGUI.logger.addHandler(logging.StreamHandler())
testGUI.logger.setLevel(logging.DEBUG)
testGUI.start()
while alive :
testGUI.updateTitle('title %s'%str(datetime.now() ))
k = testGUI.getKeyPressed()
if k is not None:
if k=='Q' :
alive = False
else :
testGUI.addMessage('unknown key %s'%k , maj=True)
sleep(0.1)
the main loop of my program instantiate and start a genericTUI object and get keypressed from it or set value to display.
But when i quit the program , my terminal is in a funny state even if I used the curses wrapper function or try to reset manually using curses.nocbreak() and others.
I can't figure what I did wrong ? Am i mistaken using curses inside a thread ??

Answer 1

I found the answer but puting it in the comment section makes it hard to read . So I also put it here :
the curses wapper does not like the thread in daemon mode :
so the following code works fine and restore the terminal in a correct state :
class GenericTUI(threading.Thread):
def __init__(self, logger=logging.getLogger()):
threading.Thread.__init__(self,name="genericTUI" + str(os.getpid()), daemon=False)
self.keyPressedList = list()
and in the stop function adding a curses.endwin() helps :
def stop(self):
curses.endwin()
self.alive = False
hope it helps other

Answer 2

#WesModes I use the stop to have a clean way to stop the TUI. The endwin is cleaning the screen .
example :
testGUI=GenericTUI()
alive = True
testGUI.start()
while alive:
try :
k = testGUI.getKeyPressed()
if k is not None:
if k== 'Q':
testGUI.stop()
alive = False