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How to get the value of an Entry created in a def?

I'm working on a project and i would like to get the Value of an Entry created in a def (turned on by a button on Tkinter)
So I have my main tkinter menu, with a button which will call the def "panier".
The def "panier" is creating the Entry "value" and another button to call a second def "calcul".
The second def "calcul" will do things with the value of Entry...
But then, in the def "calcul", when i'm trying to do value.get() it tells "NameError: name 'value' is not defined"
Here is the code, btw the Entry must be created by the def...
from tkinter import *
def panier():
value=Entry(test)
value.pack()
t2=Button(test,text="Validate",command=calcul)
t2.pack()
def calcul(value):
a=value.get()
#here will be the different calculations I'll do
test=Tk()
t1=Button(test,text="Button",command=panier)
t1.pack()
test.mainloop()
Appreciate every feedback :)

You can make the variable global like this:
from tkinter import *
def panier():
global value
value = Entry(test)
value.pack()
t2 = Button(test, text="Validate", command=calcul)
t2.pack()
def calcul():
a = value.get()
print(a)
#here will be the different calculations I'll do
test = Tk()
t1 = Button(test, text="Button", command=panier)
t1.pack()
test.mainloop()
The global value line makes the variable global so you can use it anywhere in your program.
You can also pass in the variable as an argument like what #JacksonPro suggested
t2 = Button(test, text="Validate", command=lambda: calcul(value))

This is one way to do it. Globally create a collection (list or dictionary) to hold a reference to the Entry. When you create the Entry, add it to the collection. I made it with either a list or dictionary for holding the references, so toggle the commented variations in all three places to try it both ways.
import tkinter as tk
def panier():
for item in ('value', ):
ent = tk.Entry(test)
collection.append(ent)
# collection[item] = ent
ent.pack()
t2 = tk.Button(test,text="Validate",command=calcul)
t2.pack()
def calcul():
a = collection[0].get()
# a = collection['value'].get()
print(a)
collection = []
# collection = {}
test = tk.Tk()
t1 = tk.Button(test, text="Button", command=panier)
t1.pack()
test.mainloop()

Need to track variables from multiple Tkinter checkboxes

I have a dynamically created Tkinter checkbutton widget, which takes in the contents of a list of usernames. I then displayed those names with a checkbox alongside.
What I need to do is obviously collect which usernames have been checked, so I can pass that off to another function to action.
How should I write the variable part of this so it creates a new list of chosen usernames?
What I have thus far:
def delprof_results(users_delprof):
for i in range(len(users_delprof)):
c = Checkbutton(resultsFrame, text=users_delprof[i], variable=users_delprof[i])
c.pack(anchor=W)
def delprof_del():
users_chosen = []
print str(users_delprof[i]).get() # Works up until this point. How to get individual variable with ID.
del_but = Button(resultsFrame, text="Delete", width=7, height=1, command=delprof_del)
del_but.pack(side=LEFT)
Thanks in advance,
Chris.

If you want to reach individual objects, simply keep a reference to the individual objects instead of creating objects while overwriting the same variable with each iteration of a loop like:
for i in range(30):
a = i
How to reach a's state where it was 13? Well, you can't as it's overwritten.
Instead, use collection types. In the example below I used dict:
try: # In order to be able to import tkinter for
import tkinter as tk # either in python 2 or in python 3
except ImportError:
import Tkinter as tk
def upon_select(widget):
print("{}'s value is {}.".format(widget['text'], widget.var.get()))
if __name__ == '__main__':
root = tk.Tk()
names = {"Chester", "James", "Mike"}
username_cbs = dict()
for name in names:
username_cbs[name] = tk.Checkbutton(root, text=name,
onvalue=True, offvalue=False)
username_cbs[name].var = tk.BooleanVar()
username_cbs[name]['variable'] = username_cbs[name].var
username_cbs[name]['command'] = lambda w=username_cbs[name]: \
upon_select(w)
username_cbs[name].pack()
tk.mainloop()

You could make a list of values from the checkbuttons:
values = []
for i in range(len(users_delprof)):
v = IntVar()
c = Checkbutton(master, text="Don't show this again", variable=v)
c.var = v
values.append(v)
Now you can check the value by looking in the list values, and getting the value of a checkbutton with v.get().

ttk create multiple checkbuttons

I'm trying to make a GUI that display lots of checkbuttons, i create them from a list; make a dictionary form the list and assign each checkbutton a variable from the dictionary so i can check it's state later.
Problem is that all the checkbuttons are displayed in an 'alternate' state, even if i set the variable to either 0 or 1, i've also tried changing states, but nothing seems to help.
y = 0
for x in get_dir_names(r'D:\SKL\test\win10'):
drv_check[x] = Variable()
drv_check[x].set(0)
center_window(150, 500, top_child)
drv = ttk.Checkbutton(child_frame, text=x, variable=drv_check[x])
drv.grid(row=y, column=0, sticky=W)
y += 1
for reference
def get_dir_names(dir_path):
"""Get names only of all directories from a given path (none recursive)"""
drv_list = [x for x in os.walk(dir_path).__next__()[1]]
drv_name = dict({})
for y in drv_list:
tmp_ver = dir_path + r'\\' + y
drv_name[y] = (os.walk(tmp_ver).__next__()[1]).pop()
return drv_name

Figured it out, I've made a "toggle all" button and it seemed to fix it, but it's weird that it didn't work before.
here's the function i used:
def toggle_all(*args):
while True:
if toggle_all_var.get() == '1':
for name in drv_check:
drv_check[name].set('1')
elif toggle_all_var.get() == '0':
for name in drv_check:
drv_check[name].set('0')
ttk.Checkbutton(drv_frame, text='Toggle all', variable=toggle_all_var).grid(row=y, column=0, sticky=W)
Also i run the function in a new thread.

Return statement not working python 3

The idea of this code is, the user presses the first button and enters what they want, then they press the second button and it prints it out. Can someone please tell me why my return statement is not working? It says that 'variable' is not defined. Thanks in advance for taking the time to read my question.
from tkinter import*
def fun():
variable = input('Enter Here:')
return variable
def fun_2():
print(variable)
window = Tk()
button = Button(text = 'Button', command = fun )
button2 = Button(text = 'Button2', command = fun_2 )
button.pack()
button2.pack()
window.mainloop()

In python when you create a variable inside of a function, it is only defined within that function. Therefore other functions will not be able to see it.
In this case, you will probably want some shared state within an object. Something like:
class MyClass:
def fun(self):
self.variable = input('Enter Here:')
def fun_2(self):
print(self.variable)
mc = MyClass()
window = Tk()
button = Button(text = 'Button', command = mc.fun )
button2 = Button(text = 'Button2', command = mc.fun_2 )
button.pack()
button2.pack()

fun() may return a value, but Tkinter buttons don't do anything with that return value.
Note that I used the phrase return a value, not return a variable. The return statement passes back the value of an expression, not the variable variable here. As such, the variable variable is not made into a global that other functions then can access.
Here, you can make variable a global, and tell fun to set that global:
variable = 'No value set just yet'
def fun():
global variable
variable = input('Enter Here:')
Since you did use any assignment in fun2, variable there is already looked up as a global, and it'll now successfully print the value of variable since it now can find that name.

The problem is in in fun2(). It does not get variable as an input parameter.
def fun_2(variable):
print(variable)
But note that you have to call fun_2 now with the appropriate argument. Also, as the function stands right now, there is little point in having the function if you just do a print inside of it.
Take away message: variable is not global in Python, and as such you must pass it to each function that wants to use it.

Possible to remove/deactivate variables from an executed line?

Is it possible to remove/deactivate variables from a line of code once it has been executed? If not, what are my other options? I wrote a code here to demonstrate what I mean:
from Tkinter import *
root = Tk()
ent_var1 = StringVar()
ent_var2 = StringVar()
ent_var3 = StringVar()
cbtn_var1 = BooleanVar()
cbtn_var2 = BooleanVar()
cbtn_var3 = BooleanVar()
ent1 = Entry(textvariable=ent_var1).pack()
ent2 = Entry(textvariable=ent_var2).pack()
ent3 = Entry(textvariable=ent_var3).pack()
cbtn1 = Checkbutton(text=1, variable=cbtn_var1).pack(side = LEFT)
cbtn2 = Checkbutton(text=2, variable=cbtn_var2).pack(side = LEFT)
cbtn3 = Checkbutton(text=3, variable=cbtn_var3).pack(side = LEFT)
# prints what was written in entires
def set_variables():
lbl1 = ent_var1.get()
lbl2 = ent_var2.get()
lbl3 = ent_var3.get()
print lbl1, lbl2, lbl3
return
# calls set_variables
btn1 = Button(root, text="Done!", command=set_variables).pack()
root.mainloop()
When you fill the entries and press "Done!", what was written is printed. But how do I make it so that when I press the checkboxes, the entry linked to it will not be printed the next the I press "Done!"? The checkbox with the text "1" should be linked with the first entry, and so on.
I came up with this:
def should_print():
global lbl_print
if cbtn1:
lbl_print += lbl1
if cbtn2:
lbl_print += lbl2
if cbtn3:
lbl_print += lbl3
But it would only print the values of my variables at that very moment, not the variables themselves (meaning I'd have to run this code every time a variable changes).
Thank you!

Your question is very hard to understand. I think what you want is for set_variables to only print the variables associated with a checked checkbox. If so, does the following do what you want?
def set_variables():
to_print = []
if cbtn_var1.get():
to_print.append(ent_var1.get())
if cbtn_var2.get():
to_print.append(ent_var2.get())
if cbtn_var3.get():
to_print.append(ent_var3.get())
print " ".join(to_print)
return
There are other ways to accomplish the same thing, but I'm guessing your main goal is to decide what to print based on which checkbuttons are checked. This does that, albeit in a rather ham-fisted manner.

Why don't you simply check in your set_variables function if each button is pressed? For example:
def set_variables():
if not cbtn_var1.get():
print ent_var1.get(),
if not cbtn_var2.get():
print ent_var2.get(),
if not cbtn_var3.get():
print ent_var3.get(),
print
The commas at the end of each print statement will cause it to not print a newline, which is taken care of by the print at the end. Also, this will make so that if the box is checked, the value they entered won't print. If you want it to print only if the box is checked, then remove the nots.
If you refactor your code a little bit, you can do the same thing with one line. First, add this line:
cbtn_var1 = BooleanVar()
cbtn_var2 = BooleanVar()
cbtn_var3 = BooleanVar()
buttonsAndValues = [(cbtn_var1,ent_var1), (cbtn_var2,ent_var2), (cbtn_var3,ent_var3)]
With the variables in a list, you can use a list comprehension in some Python magic:
def set_variables():
print ' '.join(value.get() for checked, value in buttonsAndValues if checked.get())
If you haven't seen list comprehensions before, I'd suggest you read up about them - they can be very handy.