Hendrik van Rooyen wrote: > "Jon Todd" <jo...en.co.uk> wrote: > > >>I'd like to have a button that when pressed executes a loop (this could be a >>thread) and then stops execution when it's released (Push to Make - Single >>Pole in electronics terms). >> >>I've tried the regular way of associating the procedure with a callback and >>tried using <Button-1> and <ButtonRelease-1> bindings but am getting nowhere >>fast (in the latter case the button release event seems to occur anyhows). >> > > > You are a bit stymied : > > Afaik, Button needs the click on the button, leaving it depressed, > while ButtonRelease needs a click on the button, and the release can be > anywhere > for drag and drop implementation. So it is possible to call two routines with > one > click and release. > > But there is another hassle - you would have to code the loop as a separate > thread, > started by the first, while the second routine sets some variable that is > checked by > the loop to kill itself, as the GUI will not be responsive until the first > command > returns, because the command "captures" the main loop... > > HTH - Hendrik > > Perhaps besides all the multithreading issues you should be looking at different kind of control/button ei. checkbox or radio button (windows terminology)?
My first experience at GUI with Tk/TCL?? was not a good one due to both lack of docs and fear it wouldn't work on both LUNUX and vindows. Wish there was a simple library with basic primitives like create_windows resize, get_client_area and of course some functions to hand of control to the system. At least for me, that way I could get much further much faster than trying to find the learn the behavior of all the currently available controls. Another point I came across recently is that there is no information on proper cleanup after TCL, don't remember exactly why it was a problem it is after all OOP sy. So, you may have to read the sourcecode for everything you are using and it ain't easy, Good Luck. Cheers. -- http://mail.python.org/mailman/listinfo/python-list
