Hello David and John, Thanks for your reactions. Sorry for the delay, was occupied with some other duties like skiing.... echo $DISPLAY from the debian command line returns nothing (a blank line). The same command form the debian command line coming from the LXDE interface gives: :0. So I issue the sudo python myprog.py command after the LXDE shell has been loaded: that works for me.I need sudo because of the Adafruit library, but I suppose that is another story. Would be great to run the program without LXDE but I guess that will not work. The next problem is: how to run the program automatically upon start-up. I prefer without LXDE but I am afraid that is not possible. So I need to start myprog.py form a kind of start-up script.... Btw: what is X11? The link is not terribly clear for me as a novice...
Best regards, Harke On Sat, Mar 26, 2016 at 10:01 PM, David Good <david.go...@gmail.com> wrote: > It looks like you need to set the DISPLAY environment variable so that > tkinter knows which display to use. > > Is X11 installed on the BBB? > > On my linux machine, when I try echo $DISPLAY, I get ":0.0" without the > quotes. > > What happens if you run that command? > > You might check out some of the info on this page as well. > > > http://unix.stackexchange.com/questions/17255/is-there-a-command-to-list-all-open-displays-on-a-machine > > --David > > On Sat, Mar 26, 2016 at 1:59 PM, John Baker <bakerengineerin...@gmail.com> > wrote: > >> Harke: >> Another in the Learned Group, I think it was Steve Plant but I can't find >> the post, suggested connecting a keyboard and mouse to the BBB and running >> the Python program with 'sudo python your_python_program'. That worked >> great for me. I never would have thought of it. My code is a GUI with >> buttons, text boxes and an animation graph running Tkinter and also running >> PyBBIO for PWM output and ADC inputs. >> John >> johnbakeree.blogspot.com >> >> On Saturday, February 13, 2016 at 3:07:04 AM UTC-8, Harke Smits wrote: >>> >>> Hello Learned Group, >>> >>> I have a BBB running Debian (2015-11-03 version) with a Chipsee 4.3 >>> display. It works great, so far so good: both in graphic mode and text. I >>> try to script an application requiring a GUI, so I loaded Tkinter and >>> entered a test program. >>> This is the result: >>> >>> Traceback (most recent call last): >>> File "testtk.py", line 2, in <module> >>> root = Tkinter.Tk() >>> File "/usr/lib/python2.7/lib-tk/Tkinter.py", line 1712, in __init__ >>> self.tk = _tkinter.create(screenName, baseName, className, >>> interactive, wantobjects, useTk, sync, use) >>> _tkinter.TclError: no display name and no $DISPLAY environment variable >>> root@beaglebone:/home/apptest# >>> >>> Its the same whether I run from BBB via bash or via another pc with >>> Cloud9. >>> >>> I googled a lot and the error is not uncommon, but could not find a clue >>> for my case. >>> >>> Please advise, regards, >>> Harke >>> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to beagleboard+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/w7vDlQctKD8/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > beagleboard+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
