[wxPython-users]Multi-thread logging to textctrl

[甜瓜]

Hi!
    I encounter a race condition in wx and logging library. In my
program, there is a textctrl in mainframe widget. There are two
threads (one is main loop, the other is a working thread) continuously
writing logtext by using logging library.

class OutputWindowStream(object):
    def __init__(self, textbox):
        # textbox presents the instance of textctrl in the mainframe
        self.textbox = textbox

    def write(self, s):
        # treat the textbox as DebugWindow. logtext will append to it.
        self.textbox.AppendText(s)

    def flush(self):
        pass

In the MainFrame.__init__, a StreamHandler is attached to root logger
in order to redirect logtext into the textbox:
        hdler = logging.StreamHandler(OutputWindowStream(self.textbox))
        self.log = logging.getLogger()
        self.log.addHandler(hdler)
Then, the mainframe start a new working thread:
        self.worker = Worker()  #
        self.worker.log = self.log
        self.worker.setDaemon(True)
        self.worker.start()
Later, both mainframe and worker start to generate output text by:
        self.log.info(...)
However, this program will deadlock randomly. If I remove the
self.log.info in one thread, it runs smoothly. Therefore, the deadlock
is made by logging library while concurrently writing text into a
textctrl widget. But logging library indeed synchronize the access to
OutputWindowStream by internal lock. I'm confused why the race
condition still occurs.

---
ShenLei