Question

I’m trying to thread wx.ProgressDialog. I got a Progress threading class

class Progress(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)
    def run(self):
        max = 1000000

        dlg = wx.ProgressDialog("Progress dialog example",
                               "An informative message",
                               maximum = max,
                               parent=None,
                               style = wx.PD_CAN_ABORT
                                | wx.PD_APP_MODAL
                                | wx.PD_ELAPSED_TIME
                                | wx.PD_ESTIMATED_TIME
                                | wx.PD_REMAINING_TIME
                                )
        keepGoing = True
        count = 0

        while keepGoing and count < max:
            count += 1
            wx.MilliSleep(250)

            if count >= max / 2:
                (keepGoing, skip) = dlg.Update(count, "Half-time!")
            else:
                (keepGoing, skip) = dlg.Update(count)
        dlg.Destroy()

which gets called when I push a button by

class MiPPanel ( wx.Panel ):
    [...]
    def runmiP(self, event):
        thread1 = Progress() 
        thread1.start() 

When I run thread1.start() I get 100s of warnings of the type 2012-12-01 00:31:19.215 Python[3235:8807] *** __NSAutoreleaseNoPool(): Object 0x11a88f300 of class NSConcreteAttributedString autoreleased with no pool in place - just leaking
and the progress bar doesn’t show up.

How can I use threading with wxPython to make a progress bar?

Answer 1

All wxPython widgets and manipulation should be in a single thread. If you want to have a dialog controlled by another thread then you will have to use timers and queues to message the dialog from the other thread.

Another way I understand is supposed to work (I have not tested this) it to create a completely separate wxApp in another thread just for your dialog. You will have to communicate somehow back to the main thread still.

Edit:
Here is a link to more information. It has some info at the bottom about using wx.CallAfter to update progress of a worker thread. It also shows how to run a single function in a separate thread without creating a separate class.

wxPython Threading