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simple tkinter question - button command (display other text on click)

i've just started learning tkinter for python, and i'm trying to get the button to change its text when it's clicked on.
this seems like a very simple question, but i can't find any answers. the code i'm using at the moment doesn't work - when the window opens, it displays 'clicked!' as a label above the button immediately, before i've clicked on the button.
from tkinter import *
root = Tk()
def click():
label = Label(root, text = 'clicked!')
label.pack()
button = Button(root, text='click me', command = click())
button.pack()
root.mainloop()

To change an existing button's text (or some other option), you can call its config() method and pass it keyword arguments with new values in them. Note that when constructing the Button only pass it the name of the callback function — i.e. don't call it).
from tkinter import *
root = Tk()
def click():
button.config(text='clicked!')
button = Button(root, text='click me', command=click)
button.pack()
root.mainloop()

You're passing command = click() to the Button constructor. This way, Python executes click, then passes its return value to Button. To pass the function itself, remove the parentheses - command = click.

Tkinter checkbox executing command only once [duplicate]

This question already has answers here:
Why is my Button's command executed immediately when I create the Button, and not when I click it? [duplicate]
(5 answers)
Closed 1 year ago.
x = tk.IntVar()
def test():
print(x.get())
checkBox = tk.Checkbutton(text="test",command=test(),variable=x)
checkBox.grid(row=12,column=2)
b=tk.Button(text="test",command=test)
b.grid(row=12,column=0
this is some code I put in my program for testing, when I check the checkbox the value does change (I can confirm it with the button I made to test) but the command does not get executed.

Remove () in command
command= test
This works fine:
import tkinter as tk
win = tk.Tk()
x = tk.IntVar()
def test():
print(x.get())
checkBox = tk.Checkbutton(text="test", command=test, variable=x)
checkBox.grid(row=12, column=2)
win.mainloop()

How to disable a button in tkinter? [duplicate]

This question already has answers here:
Disable / Enable Button in TKinter
(2 answers)
Closed 2 years ago.
When I click a button a new button displays but I want the previous clicked button to be disabled.
import tkinter as tk
def newbutton():
newbtn = tk.Button(app, text = "New Window button")
newbtn.pack()
app = tk.Tk()
buttonExample = tk.Button(app, text="Create new window", command=newbutton)
buttonExample.pack()
app.mainloop()

hi there have you tried to use the state command like this
buttonExample = tk.Button(app, text="Create new window", command=newbutton, state=DISABLED)

You can implement a very simple function that can disable a button
def disableButton(my_button):
my_button.config(state='disabled')
There is already a post on stack talking about that here

Display Path of a file in Tkinter using "browse" Button - Python [duplicate]

This question already has answers here:
Why is my Button's command executed immediately when I create the Button, and not when I click it? [duplicate]
(5 answers)
Closed 6 years ago.
I have been reading through several posts regarding to Browse button issues in Tkinter but I could not find my answer.
So I have wrote this code to get a directory path when clicking the browse button, and displaying this path in an entry field.
It woks partly : a file browser window directly pops up when I run the script. I indeed get the path in the entry field but if I want then to change the folder using my Browse button it does not work.
I dont want to have the browser poping up right from the start but only when I click on Browse !
Thanks for your answers
from Tkinter import *
from tkFileDialog import askdirectory
window = Tk() # user input window
MyText= StringVar()
def DisplayDir(Var):
feedback = askdirectory()
Var.set(feedback)
Button(window, text='Browse', command=DisplayDir(MyText)).pack()
Entry(window, textvariable = MyText).pack()
Button(window, text='OK', command=window.destroy).pack()
mainloop()

This is so easy -- you need to assign the path to a variable and then print it out:
from tkinter import *
root = Tk()
def browsefunc():
filename = filedialog.askopenfilename()
pathlabel.config(text=filename)
browsebutton = Button(root, text="Browse", command=browsefunc)
browsebutton.pack()
pathlabel = Label(root)
pathlabel.pack()
P.S.: This is in Python 3. But the concept is same.

Sending a variable with a button-command (python 3.3 / tkinter) [duplicate]

This question already has an answer here:
How to use os.startfile with a button command (TkInter)
(1 answer)
Closed 9 years ago.
I want to update a Tkinter label when a button is clicked.
The following code works fine:
import tkinter
from tkinter import *
window = tkinter.Tk()
v="start"
lbl = Label(window, text=v)
lbl.pack()
def changelabel():
v ="New Text!"
lbl.config(text=v)
btn=Button(window, text="Change label text", command=changelabel)
btn.pack()
window.mainloop()
But for more dynamics I would like the New text to be sent into the changelabel-function.
I've tried a lot of things. This is what I think should work, but it prints the "New dynamic text" right away, instead of waiting for my click...
import tkinter
from tkinter import *
window = tkinter.Tk()
v="start"
lbl = Label(window, text=v)
lbl.pack()
def changelabel(v):
lbl.config(text=v)
v ="New, dynamic text!"
btn=Button(window, text="Change label text", command=changelabel(v))
btn.pack()
window.mainloop()
Do you understand my error?

You need to "hide" the call to changelabel. The easiest way to do this is to use a lambda:
btn=Button(window, text="Change label text", command=lambda: changelabel(v))
Otherwise, when Python runs through your code, it sees this:
changelabel(v)
Interpreting it as a valid function call, it runs it.