Mailman 3 June 2009 - Tkinter-discuss

Tkinter Geometry Management and Other Basics
by Wayne Watson July 26, 2009

July 26, 2009

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Canvas postscript fun
by Bob Greschke June 29, 2009

June 29, 2009

After about 5 years of on and off goofing around I finally, yesterday, got the Canvas postscript command to produce a postscript file with ALL of the contents of a canvas in it, instead of just what was visible at the time. This did it: L, T, R, B = LCan.bbox(ALL) Ps = LCan.postscript(height = B, width = R, pageheight = B, \ pagewidth = R, x = 0, y = 0) The write Ps to a file. The problem is the Canvas in the program I have is 8000 pixels wide by 1000 pixels tall (or bigger or smaller). Anything that wants to print the file wants to keep everything squished on to one page. Is there a way through the command to get downstream programs to "span" the image across more than one page (I'd maybe have to calculate something on-the-fly, but that would be OK)? A screen shot of what I'm trying to print is here. It's in the out.pdf Preview program (OS X) window: www.passcal.nmt.edu/~bob/unlinked/images/big.tiff Thanks! Bob

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Forcing a window to update with while loop running
by Adam Kadzban June 23, 2009

June 23, 2009

Hi again, let me start off by saying that my code does what I want it to, it's just done in a terribly hackish way, and I'm wondering if there's a better way to do it. I've got a Tkinter window, and when you click a button (the 'run' button), it opens a new window. When the new window opens, it starts running events in a while loop, and there's a 'stop' button on the window. The stop button just turns the 'while' condition variable to 0, so the loop ends. Here's a quick sketch of how I got it to work: ... loop = 1 ... (create a button that sets loop to 0) ... top.update() ... while loop: top.update() ...do stuff... top.update() This works, but I feel like there's got to be a better way to be doing this. I can get rid of the first top.update(), and one of the updates in the loop, but this configuration seems to be the most responsive. And using update_idletasks() doesn't seem to work, at all. Anyone have an idea? -Adam

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Communicating between objects w/o class and/or global?
by GKalman June 23, 2009

June 23, 2009

Recently I posted, on this Forum, a msg titled: "Tkinter mouse-event w/o class and/or global?" It was successfuly [RESOLVED] . ow I have related Question: I have two (c1 & c2) Canvas instances. If I mouse-click on one of the canvases (or more likely on a drawn item on the canvas, e.g. on a rectangle), I would like to change the background color of the other canvas. Can I do it without classes (OOP) and/or global-variables? -- View this message in context: http://www.nabble.com/Communicating-between-objects-w-o-class-and-or-global… Sent from the Python - tkinter-discuss mailing list archive at Nabble.com.

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Tkinter mouse-event w/o class and/or global?
by GKalman June 22, 2009

June 22, 2009

As an example: I want to click on a Canvas and with that change its background color. The "usual" way is to declare a class (i.e a namespace). An other way is declare c=Canvas(...) as global. Question: Is it possible to do this without a class (OOP) or global variables? -- View this message in context: http://www.nabble.com/Tkinter-mouse-event-w-o-class-and-or-global--tp241459… Sent from the Python - tkinter-discuss mailing list archive at Nabble.com.

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locking window size?
by GKalman June 14, 2009

June 14, 2009

How to "lock" top window size with 2 different Frames on it ? I would like to "freeze" the size of the top window, so it can't be changed with the mouse for example: #============================================== from Tkinter import * root=Tk() root.geometry("300x100+10+10") f1=Frame(root,bg="red", width=100,height=100) f1.pack(side=LEFT, expand=0) f2=Frame(root,bg="blue",width=200, height=100) f2.pack(side=LEFT, expand=0) root.mainloop() -- View this message in context: http://www.nabble.com/locking-window-size--tp24003215p24003215.html Sent from the Python - tkinter-discuss mailing list archive at Nabble.com.

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IntVar() not being attached to Checkbutton
by Adam Kadzban June 11, 2009

June 11, 2009

Hi, I'm having some problems with my Checkbuttons. I'm giving them IntVars to bind to, but there seems to be no relationship between the IntVars and the buttons. This is the first time I've had problems with this, I've used IntVars with Checkbuttons in the past with no such trouble. I have the main part of the GUI (which has Checkbuttons that behave normally), with a menu option to create another window for some "advanced options". The code for this window is in its own class, which takes a list of options as parameters and then has some check boxes and entry boxes so you can change the option list. Here's the relevant code: ... self.tVar = IntVar() ... self.tempbutton = Checkbutton(self.tophalf,variable=self.tVar,text="Calculate temperature") ... When I try the program with this code, I can check/uncheck the boxes, but tVar never change (I printed out their values, they stay 0). I also tried coding in button selection (e.g. self.tempbutton.select()), but tVar never changes. I also tried making some functions, and binding them to the checkbutton: self.tempbutton = Checkbutton(self.tophalf,variable=self.tVar,text="Calculate temperature",command=self.checkTemp) ... def checkTemp(self): if self.tVar.get() == 1: self.tempbutton.select() else: self.tempbutton.deselect() ... Having that, though, doesn't let me "check" the button (I'm guessing because tVar never gets set to 1, it always goes to deselect). Anyone have any ideas why this is happening? I've been banging my head against a wall here, and I rewrote the whole class thinking maybe it was something funny with scoping, but as far as I can tell everything is ok. I must be missing something... Thanks, Adam

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Adding <Command-Button-1> to a Listbox
by Bob Greschke June 7, 2009

June 7, 2009

I'd like to add <Command-Button-1> (i.e. use the Command key on a Mac) event handling to a Listbox so that it behaves just like the <Control- Button-1> "built-in" behavior (selecting/deselecting individual items when the selectmode is EXTENDED). What should the bind statement call to do that? Can it be done through something like an option_add so it applies to all listboxes in an application? Thanks! Bob

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Leak with Entry on Mac ( 8.5.7 / 2.6.2 )?
by Art Botterell June 6, 2009

June 6, 2009

Hi, new Python/Tkinter adopter here! I'm building a little screen display to show status of a remote device (a radio scanner) in an MVC pattern. In the top-level "view" GUI object I'm updating the text in three Entry fields and the background color of a Frame, all at a rate of about five cycles per second. Works fine except it leaks memory at a rate of between 1-2K per second. As best I can tell the problem seems to be down in Tkinter: I can pass- out the set() calls to the StringVars and the color update and leave everything else and my memory consumption stablizes. I can also induce a leak by making get()s. I tried bypassing the StringVar mechanism and doing delete()/insert() directly on the Entry widgets... that didn't seem to solve it either. Googling around I can see that there've been various memory leak issues in past history, but I don't see any open issues with 8.5.7 and/ or Python 2.6.2. So I wonder if maybe I'm just making a noobish mistake in my own code (please see below.) I'm admitting my helplessness and pleading for help. TIA! - Art #! /usr/bin/env python ''' Created on June 5, 2009 @author: acb ''' from Tkinter import * import tkFont import time import Controller import threading import sys import signal class Display: def shutdown(foo): sys.exit() def __init__(self, root): # define display fonts self.sans1 = tkFont.Font( family="sanserif", size=24) self.sans2 = tkFont.Font( family="sanserif", size=12) # shutdown on window close and on control-c root.protocol("WM_DELETE_WINDOW", self.shutdown) def exit_handler( signal, frame ): self.shutdown() signal.signal(signal.SIGINT, exit_handler) # Set up the display frame and fields self.toppad = Frame(root, height=4) self.toppad.pack() self.display = Frame(root) self.indisplay = Frame(self.display, background="#ffffff") self.spacer = Frame(self.indisplay, height=5) self.spacer.pack(expand=YES) self.freq = Entry(self.indisplay) self.freqString = StringVar() self.freq.config(justify=CENTER, font=self.sans2, borderwidth=0, textvariable=self.freqString) self.freq.pack(padx=10, pady=5) self.label = Entry(self.indisplay) self.labelString = StringVar() self.label.config(justify=CENTER, font=self.sans1, borderwidth=0, width=12, textvariable=self.labelString) self.label.pack(padx=10, pady=5) self.object = Entry(self.indisplay) self.objectString = StringVar() self.object.config(justify=CENTER, font=self.sans2, borderwidth=0, textvariable=self.objectString) self.object.pack(padx=10, pady=5) self.spacer = Frame(self.indisplay, height=5) self.spacer.pack(expand=YES) self.indisplay.config() self.indisplay.pack( fill=BOTH, padx=2, pady=2 ) self.display.pack(fill=BOTH, padx=5) # Set up controls self.control = Canvas(root) self.keycode = 0 self.manBtn = Button(self.control, text="Manual") self.manBtn.pack(side=LEFT,padx=20) self.manBtn['command']=lambda: self.keyset(3) self.upBtn = Button(self.control, text="Up") self.upBtn.pack(side=LEFT,expand=YES,padx=10) self.upBtn['command']=lambda: self.keyset(7) self.dnBtn = Button(self.control, text="Dn") self.dnBtn.pack(side=LEFT,expand=YES,padx=10) self.dnBtn['command']=lambda: self.keyset(9) self.scnBtn = Button(self.control, text="Scan") self.scnBtn.pack(side=RIGHT,padx=20) self.scnBtn['command']=lambda: self.keyset(15) self.control.pack(fill=X, ipady=2, pady=4) self.controller = Controller.Controller(self) # command to send a keystroke to the scanner def keyset(self, value): self.controller.send_key(value) # commands to update the display fields (called from the controller) def set_freq(self, text): self.freqString.set(text) def set_label(self, text): self.labelString.set(text) def set_object(self, text): self.objectString.set(text) def set_color(self, text): self.display['background']=text root = Tk() disp = Display(root) root.wm_title("PSR-600 Remote v0.4") root.mainloop()

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