The grid, pack and place functions of the Entry object and of all other widgets returns None. In python when you do a().b(), the result of the expression is whatever b() returns, therefore Entry(…).grid(…) will return None. You should split that on to two lines like this: entryBox = Entry(root, width=60) entryBox.grid(row=2, column=1, sticky=W) That … Read more
The simplest (but possibly inaccurate) method is to use tk::PlaceWindow, which takes the pathname of a toplevel window as an argument. The main window’s pathname is . import tkinter root = tkinter.Tk() root.eval(‘tk::PlaceWindow . center’) second_win = tkinter.Toplevel(root) root.eval(f’tk::PlaceWindow {str(second_win)} center’) root.mainloop() The problem Simple solutions ignore the outermost frame with the title bar and … Read more
Probably the vast majority of of tk-based applications place all the components in the default root window. This is the most convenient way to do it since it already exists. Choosing to hide the default window and create your own is a perfectly fine thing to do, though it requires just a tiny bit of … Read more
Add a Tkinter StringVar to your Entry widget. Bind your callback to the StringVar using the trace method. from Tkinter import * def callback(sv): print sv.get() root = Tk() sv = StringVar() sv.trace(“w”, lambda name, index, mode, sv=sv: callback(sv)) e = Entry(root, textvariable=sv) e.pack() root.mainloop()
Here’s example code adapted from the VerticalScrolledFrame page on the now defunct Tkinter Wiki that’s been modified to run on Python 2.7 and 3+. try: # Python 2 import tkinter as tk import tkinter.ttk as ttk from tkinter.constants import * except ImportError: # Python 2 import Tkinter as tk import ttk from tkinter.constants import * … Read more
You have to change the state of the Text widget from NORMAL to DISABLED after entering text.insert() or text.bind() : text.config(state=DISABLED)
This happens if you are trying to open a file, but your path is a folder. This can happen easily by mistake. To defend against that, use: import os path = r”my/path/to/file.txt” assert os.path.isfile(path) with open(path, “r”) as f: pass The assertion will fail if the path is actually of a folder.
Tkinter root windows have a method called after which can be used to schedule a function to be called after a given period of time. If that function itself calls after you’ve set up an automatically recurring event. Here is a working example: # for python 3.x use ‘tkinter’ rather than ‘Tkinter’ import Tkinter as … Read more
tk.mainloop() blocks. It means that execution of your Python commands halts there. You can see that by writing: while 1: ball.draw() tk.mainloop() print(“hello”) #NEW CODE time.sleep(0.01) You will never see the output from the print statement. Because there is no loop, the ball doesn’t move. On the other hand, the methods update_idletasks() and update() here: … Read more
Consider this code: b = Button(admin, text=”as”, command=button(‘hey’)) It does exactly the same as this: result = button(‘hey’) b = button(admin, text=”as”, command=result) Likewise, if you create a binding like this: listbox.bind(“<<ListboxSelect>>”, some_function()) … it’s the same as this: result = some_function() listbox.bind(“<<ListboxSelect>>”, result) The command option takes a reference to a function, which is … Read more