Re: Python sleep doesn't work right in a loop?
I appreciate all the responses. It IS possible that wx and/or python is whacked on my machine. I've got python 2.2 and 2.3 installed, I have installed and uninstalled 2.4, I've had about three versions of wx installed along the way for different programs, so it is possible that it is just my machine. Nevertheless, I came here looking for ideas, and you've given me some good ones: some I had already tried (but I like validation) and some were new to me. Thanks, all. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
On Wed, 06 Apr 2005 12:49:51 -0700, ritterhaus wrote: > Nope. Does't work. Running Python 2.3.4 on Debian, Linux kernel 2.6. This > is actually test code for a larger project... > > # flash the selected wx.TextControl > > for flasher in range(4): > self.textField.SetBackgroundColour(255, 0, 0) time.sleep(0.8) > self.textField.SetBackgroundColour(255, 255, 223) time.sleep(0.8) > > Even when I add an explicit call to repaint the TextCtrl between each > sleep, things appear to be 'queued' until after the loop is fnished. Very > bizarre. GUIs don't like "time.sleep". All of them come with some sort of "fire a timing event in X milliseconds and call this handler". Use that instead. I believe wx's is the wxTimer class, and the wxFutureCall class looks promising. If you want to maintain the same basic calling structure, start playing games with generators; you can write the same function with "yield", and then call .next() on an iterator every time the timeout triggers. Best of both worlds. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
[EMAIL PROTECTED] wrote: > Actually, I've tried ALL of these things, and none of them work. I HAVE > run the simple for-print-sleep test code to try to determine if this > issue was specific to wx (that's good troubleshooting, folks - you > narrow down the problem) and even that didn't work, so I thought I'd > start with the simple problem first. Sorry if you were mislead. But it _is_ no problem - the code you gave us works for me and others as expected - on a very similar system, btw. So there _is_ a difference - do you call the script from an ide, pipe it or something similar? And as you yourself found that 4 time.sleep(2) produce 8 seconds timeout in total, it is pretty obvious that the problem is _not_ time.sleep - but that whatever effect you want to produce between the calls is not happening. For the print, we gave you some suggestions. > As for wx, I HAVE used the for-setColour-refresh-update-sleep loop, > still no dice. The last thing the I put in the loop works (again, as if > all the changes are being queued) but the sleep just 'takes over' the > loop and nothing happens until al the sleeps are done. With or without > wx. Not good. certainly not good - maybe you should read this http://fraca7.free.fr/blog/index.php?2005/04/04/10-a-word-about-guis One quote from the comments: ''' I am working on a major project, using Python+Twisted. I started using wxPython for the GUI, then discovered that it was completely unuseable. The wxWidgets event loop is hidden away, and the only way Twisted can integrate (the reactor) is to set a timer and run for a few cycles every so often. The resulting app does not paint properly, has huge lags, and is basically useless. I rewrote it using PyGtk and the GUI is nice and smooth, thanks to the flexible event loop design. I am not likely to use wxWidgets again, I've had many stability problems with it under both Linux and Mac, and the current stable version doesn't even support the latest Gtk. So that's my rant too I guess, agree with all you wrote above. ''' If you can live without windows compatibility - or wait for qt4 - and the GPL, I suggest a switch to qt. Sleep does not "takeover" a loop - there is no semantics defined for that. Try putting the flushes after the prints, and you'll see things work. What wx influences are on this I can't say - but the quote above suggests that event handling is not as straight in wx as it should be. -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
Actually, I've tried ALL of these things, and none of them work. I HAVE run the simple for-print-sleep test code to try to determine if this issue was specific to wx (that's good troubleshooting, folks - you narrow down the problem) and even that didn't work, so I thought I'd start with the simple problem first. Sorry if you were mislead. As for wx, I HAVE used the for-setColour-refresh-update-sleep loop, still no dice. The last thing the I put in the loop works (again, as if all the changes are being queued) but the sleep just 'takes over' the loop and nothing happens until al the sleeps are done. With or without wx. Not good. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
> Nope. Does't work. Running Python 2.3.4 on Debian, Linux kernel 2.6. > This is actually test code for a larger project... No Nope - it _does_ work. Did you actually try it? Because you use it in a wrong context does not mean that it doesn't work. Besides, giving a wrong example to prove a point is always a bad idea. > # flash the selected wx.TextControl > > for flasher in range(4): > self.textField.SetBackgroundColour(255, 0, 0) > time.sleep(0.8) > self.textField.SetBackgroundColour(255, 255, 223) > time.sleep(0.8) > > Even when I add an explicit call to repaint the TextCtrl between each > sleep, things appear to be 'queued' until after the loop is fnished. > Very bizarre. That's a totally different thing - no idea how wx works in detail, but the behaviour you describe looks as if the calls to SetBackgroundColour are queued until the event loop is processed again. So check how to do that manually between calls, and things are most probably working. Again - giving the above example would made us give you that advice way earlier - and saved us digging in the wrong direction... -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
[EMAIL PROTECTED] wrote: Nope. Does't work. Running Python 2.3.4 on Debian, Linux kernel 2.6. This is actually test code for a larger project... # flash the selected wx.TextControl for flasher in range(4): self.textField.SetBackgroundColour(255, 0, 0) time.sleep(0.8) self.textField.SetBackgroundColour(255, 255, 223) time.sleep(0.8) Even when I add an explicit call to repaint the TextCtrl between each sleep, things appear to be 'queued' until after the loop is fnished. Very bizarre. Not at all, but completely unrelated to your initial question. You need to use a specific call before each sleep to tell wxPython to update the display, since the sleep doesn't give control back to the display subsystem. I think the call you need is app.Yield(), but the docs will confirm that. regards Steve -- Steve Holden+1 703 861 4237 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Python Web Programming http://pydish.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
[EMAIL PROTECTED] wrote: Nope. Does't work. Running Python 2.3.4 on Debian, Linux kernel 2.6. This is actually test code for a larger project... # flash the selected wx.TextControl for flasher in range(4): self.textField.SetBackgroundColour(255, 0, 0) self.textField.Update() time.sleep(0.8) self.textField.SetBackgroundColour(255, 255, 223) self.textField.Update() time.sleep(0.8) Even when I add an explicit call to repaint the TextCtrl between each sleep, things appear to be 'queued' until after the loop is fnished. Very bizarre. If you use .Refresh() request still queued. /m -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
Nope. Does't work. Running Python 2.3.4 on Debian, Linux kernel 2.6. This is actually test code for a larger project... # flash the selected wx.TextControl for flasher in range(4): self.textField.SetBackgroundColour(255, 0, 0) time.sleep(0.8) self.textField.SetBackgroundColour(255, 255, 223) time.sleep(0.8) Even when I add an explicit call to repaint the TextCtrl between each sleep, things appear to be 'queued' until after the loop is fnished. Very bizarre. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
This is running in the interactive 'PyShell', but in truth those print statements are part of a gui app that flashes a control in wx.widgets by toggling it's background color. The same behavior either way. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
[EMAIL PROTECTED] wrote: > Just a simple bit of code to toggle between two state at intervals... > > import time > for i in range(4): > print 'On' > time.sleep(1) > print 'Off' > time.sleep(1) > > ... SHOULD toggle On and Off four times with one-second pauses. When I > run this, the loop pauses the full eight seconds then prints the Ons > and Offs all at once. What's up with that? Works for me - on a terminal using linux. BUT what not works is this: python /tmp/test.py | cat (test.py contains your code of course) The reason is buffered pipes being used. Try this: import time, sys for i in range(4): print 'On' sys.stdout.flush() time.sleep(1) print 'Off' sys.stdout.flush() time.sleep(1) -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
[EMAIL PROTECTED] wrote: ... SHOULD toggle On and Off four times with one-second pauses. When I run this, the loop pauses the full eight seconds then prints the Ons and Offs all at once. What's up with that? Run your script as: python -u script.py for unbuffered output. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python sleep doesn't work right in a loop?
For me it works fine. It seems that for you stdout is not flushed correctly in your terminal. What kind of terminal are you writing to? -- http://mail.python.org/mailman/listinfo/python-list
Python sleep doesn't work right in a loop?
Just a simple bit of code to toggle between two state at intervals... import time for i in range(4): print 'On' time.sleep(1) print 'Off' time.sleep(1) ... SHOULD toggle On and Off four times with one-second pauses. When I run this, the loop pauses the full eight seconds then prints the Ons and Offs all at once. What's up with that? -- http://mail.python.org/mailman/listinfo/python-list
