Develop Reference

RadioButton not selected tkinter

I've been learning tkinter and I ran into this thing I don't understand, what does it mean when a radio button has a '-'? it's like is neither marked nor unmarked, is it not returning anything?
I grabbed this code from the internet so anyone can see what I mean:
from tkinter import *
root = Tk()
btn1 = StringVar()
def do_something():
val0 = entry1.get()
val1 = btn1.get()
print("The variable values are " + val1 + " and " + val0)
print("The method values are " + btn1.get() + " and " + entry1.get())
rb1 = Radiobutton(root, text="Euro", value="euro",
variable=btn1).grid(row=2, column=1, sticky=W)
rb2 = Radiobutton(root, text="Dollar", value="dollar",
variable=btn1).grid(row=3, column=1, sticky=W)
rb3 = Radiobutton(root, text="Yen", value="yen",
variable=btn1).grid(row=4, column=1, sticky=W)
label1 = Label(root, text="Input Here")
label1.grid(row=1, sticky=E)
entry1 = Entry(root)
entry1.grid(row=1, column=1, sticky=W)
go = Button(root, text="Print Selection", fg="white",
bg="black", command=do_something)
go.grid(row=10, columnspan=3)
root.mainloop()
This happened to me in a class as well, a group of radio buttons have this hyphen in them until I bound self to the StringVar(), what's happening under the hood?

Use IntVar() instead of StringVar(). In Python 3.8+ Used f-string format.
Here is code:
from tkinter import *
root = Tk()
btn1 = IntVar()
def do_something():
val0 = float(entry1.get())
val1 = val0
print(f"The variable values are {val1} and {val0}")
print(f"The method values are {val1} and {val0}")
rb1 = Radiobutton(root, text="Euro", value="euro",
variable=btn1).grid(row=2, column=1, sticky=W)
rb2 = Radiobutton(root, text="Dollar", value="dollar",
variable=btn1).grid(row=3, column=1, sticky=W)
rb3 = Radiobutton(root, text="Yen", value="yen",
variable=btn1).grid(row=4, column=1, sticky=W)
label1 = Label(root, text="Input Here")
label1.grid(row=1, sticky=E)
entry1 = Entry(root)
entry1.grid(row=1, column=1, sticky=W)
go = Button(root, text="Print Selection", fg="white",
bg="black", command=do_something)
go.grid(row=10, columnspan=3)
root.mainloop()
Result before:
Result after:

how to display a statement in text widget of tkinter after getting input thru get statement

from tkinter import *
def tell_story(Male):
story= "My name is" + "Male"
Frame.story_txt.delete(0.0, END)
Frame.story_txt.insert(0.0, story)
root = Tk()
root.title("game")
root.geometry("800x400")
Application = Frame(root)
Application.grid()
Lbl1 = Label(Application, text="story").grid(row=0, column=0, sticky=W)
Lbl2 = Label(Application, text="Male name").grid(row=1, column=0, sticky=W)
Male = Entry(Application).grid(row=1, column=1, sticky=W)
Button(Application, text="Click for story", command=tell_story).grid(row=11, column=0, sticky=W)
Frame.story_txt = Text(Application, width=75, height=10, wrap=WORD)
Frame.story_txt.grid(row=12, column=0, columnspan=4)
root.mainloop()
I'm unable to print story variable in text widget

Why does this not add?

I've looked other questions and have tried to fix this but I am really struggling with having my code print back the answer.
from tkinter import *
root = Tk()
label1 = Label(root, text="Number 1")
label2 = Label(root, text="Number 2")
labelplus = Label(root, text="+")
label1.grid(row=0, sticky=E)
label2.grid(row=3, sticky=E)
labelplus.grid(row=2, column=1)
entry1_var= StringVar()
entry2_var= StringVar()
entry1 = Entry(root, textvariable= entry1_var)
entry2 = Entry(root, textvariable= entry2_var)
entry1.grid(row=0, column=1)
entry2.grid(row=3, column=1)
first = (entry1_var.get()
second =(entry2_var.get()
def additionStuff(event):
totalNumbers = (first + second)
print(totalNumbers)
button1 = Button(root, text="Add Numbers")
button1.bind("<Button-1>", additionStuff)
button1.grid(row=4, column=1)
root.mainloop()
Why does my function now print back the answer?

You need to call StringVar.get inside of additionStuff:
def additionStuff(event):
first = entry1_var.get()
second = entry2_var.get()
totalNumbers = (float(first) + float(second))
print(totalNumbers)
Otherwise you're getting the value of first and second before the user has had opportunity to enter anything.

Using StringVar data as a list

I've been following this website for a while. It is really helpful. So, thanks for all the useful tips.
I've been searching for this answer for the past two weeks without any success, so now I'm compelled to ask out of total frustration with my current obstacle.
How do you use StringVar as a list?
Basically, I was coding the following program for my wife. The code is pretty messy as it is my first program I've tried to code.
The idea was that I would take 3 variables; password, secret number and website and then do some work on them using if statements and lists to create a unique password.
First problem was that I couldn't restrict the character length of the entry widgets but in the end i solved that but i still want to limit the characters that can be input.
for instance in the website entry box, i want to allow only letters.
If I could convert StringVar to a list, I could do some work with messy if statements to allow only certain characters in each index but everythime i try it says that stringvars cant be used as a list.
I need them as a list to limit the type of characters that can be entered and also so that i can do work on the variables to get the final output.
CODE:
from Tkinter import *
import Tkinter
from PIL import Image, ImageTk
import os
Title= ("Helvetica", 20, "bold", "underline")
Heading= ("Courier", 20, "bold")
Body= ("Courier", 15)
Body1= ("Courier", 15, "bold")
notice= ("Courier", 10)
Body2= ("Courier", 15, "bold", "underline")
root = Tk()
root.title("Koala Series: Encrypter")
root.configure(background="#ffefd5")
root.geometry('{}x{}'.format(510, 600))
root.columnconfigure(0, weight=1)
root.rowconfigure(0, weight=1) # not needed, this is the default behavior
root.rowconfigure(1, weight=1)
root.rowconfigure(2, weight=1)
website = StringVar()
Titlemsg = Label(root, text="Koala Encrypter", font=Title, bg="#00FA9A", relief=RAISED,)
Titlemsg.grid( row=7, pady=25, sticky=N+S+E+W)
img1 = ImageTk.PhotoImage(Image.open("koala.jpeg"))
startpic = Label(root, image = img1, relief=RIDGE )
startpic.grid( row=10,pady=25, )
Head = Label(root,anchor=CENTER,text="Welcome to the Koala Encrypter \n\n A Koala series tool that allows you\n\n to Encrypt your passwords \n\n Click \'Start Encrypting\' to continue \n\n", font=Body, bg="#ffefd5", relief=RAISED,)
Head.grid( row=14, pady=25, columnspan=2, sticky=N+S+E+W)
web = Label(root, text="WEBSITE: ", font=Body, bg="#ffefd5", justify=CENTER,)
#website.set("Enter your website here")
entry = Entry(root,textvariable=website , justify=CENTER,relief=SUNKEN,cursor="pencil", takefocus=True )
Notice1 = Label( text="Please only insert the first 5 letters of the website!!",font=notice, bg="#ffefd5", fg="#0000ff",)
passw = Label(root, text="PASSWORD: ", font=Body, bg="#ffefd5", justify=CENTER)
passwordvar= StringVar()
entry1 = Entry(root, textvariable= passwordvar, justify=CENTER,relief=SUNKEN, cursor="pencil", takefocus=True )
Notice= Label(root, text="Your password must only be 5 characters long!!", font=notice, bg="#ffefd5", fg="#0000ff", justify=CENTER)
def callback(event):
if "<0>":
top = Toplevel(bg="#ffefd5")
top.title("Koala Encrypter")
popuptitle = Label(top, text="Your secret number must be between 1 and 9:", font=Body1, fg="red", bg="#ffefd5")
popuptitle.grid(row = 2,column=0, padx=5, pady = 50,sticky=N+S+E+W)
secret = Label(root, text="SECRET NUMBER: ", font=Body, bg="#ffefd5" , justify=CENTER,)
numbervar = StringVar()
entry2 = Entry(root, textvariable=numbervar , justify=CENTER,relief=SUNKEN,cursor="pencil", takefocus=True)
entry2.bind("<0>", callback)
Notice2 = Label(root, text="your secret number must be between 1 and 9!!!", font=notice, bg="#ffefd5", fg="#0000ff", justify=CENTER)
img = ImageTk.PhotoImage(Image.open("Koalalogo.jpg"))
panel = Label(root, image = img, relief=SUNKEN)
correct= Label(root, text="Check the below details \n\n Click \'yes\' if they are correct \n\n Click \'No\' to go back \n\n", font=Body1, bg="#ffefd5")
yourwebsite = Label(root, text="The Website is :", font=Body, bg="#ffefd5")#
website1 = Label(root, font=Body2, bg="#ffefd5",fg= "#00009C", textvariable = website)#
yourpassword = Label(root, text="Your Password is:", font=Body, bg="#ffefd5")
yournumber1= Label(root, font=Body2, bg="#ffefd5",textvariable = numbervar , fg= "#00009C", )
yourpassword1 = Label(root, font=Body2, bg="#ffefd5",textvariable = passwordvar , fg= "#00009C", )
yournumber= Label(root, text="Your Secret Number is:", font=Body, bg="#ffefd5")
def restart():
Titlemsg.grid_forget()
correct.grid_forget()
yourwebsite.grid_forget()
website1.grid_forget()
yourpassword.grid_forget()
yourpassword1.grid_forget()
yournumber.grid_forget()
yournumber1.grid_forget()
panel.grid_forget()
toolbar.grid_forget()
yes.grid_forget()
no.grid_forget()
entry.delete(0,END)
entry1.delete(0,END)
entry2.delete(0,END)
Titlemsg.grid( row=7, pady=25, sticky=N+S+E+W)
startpic.grid( row=10,pady=25, )
Head.grid( row=14, pady=25, columnspan=2, sticky=N+S+E+W)
toolbar.grid( row=21, )
end.grid(column =3, row=1, sticky=N+S+E+W)
begin.grid(column =2, row=1, sticky=N+S+E+W)
def start():
#entry.destroy()
#entry1.destroy()
#entry2.destroy()
toolbar.grid_forget()
Titlemsg.grid_forget()
begin.grid_forget()
Head.grid_forget()
startpic.grid_forget()
web.grid(row=3, column=0, sticky= W+E)
entry.grid( row=3, column=1, padx=50)
passw.grid(row=10, column=0)
Notice1.grid(row=4, sticky=N+S+E+W, columnspan=2)
entry1.grid(row=10, column=1)
Notice.grid(row=11,column=0, columnspan=2,)
secret.grid(row=13, column=0)
entry2.grid( row=13, column=1)
Notice2.grid( row=14,column=0, columnspan=2,)
panel.grid(row=20,columnspan=2, pady=70)
confirm.grid(column =1, row=1)
reset.grid(column =2, row=1)
end.grid(column =3, row=1)
toolbar.grid(row=21, column=0, columnspan=2)
Titlemsg.grid(row=0, column=0, columnspan=2, sticky=E+W)
def Reset():
entry.delete(0,END)
entry1.delete(0,END)
entry2.delete(0,END)
def clear_text():
#entry.destroy()
#entry1.destroy()
#entry2.destroy()
panel.grid_forget()
entry.grid_forget()
entry1.grid_forget()
entry2.grid_forget()
web.grid_forget()
Notice.grid_forget()
passw.grid_forget()
secret.grid_forget()
Notice1.grid_forget()
Notice2.grid_forget()
confirm.grid_forget()
reset.grid_forget()
toolbar.grid_forget()
Titlemsg.grid_forget()
Titlemsg.grid(row=0, column=0, columnspan=2, sticky=E+W)
correct.grid(row=1, column=0, columnspan=2, sticky=E+W)
yourwebsite.grid(row=2,column=0,sticky=E+W, pady=5)
website1.grid(row=2, column=1, padx=65,sticky=E+W, pady=5)
yourpassword.grid(row=4, column=0,sticky=E+W, pady=5)
yourpassword1.grid(row=4, column=1, padx=65,sticky=E+W, pady=5)
yournumber.grid(row=6, column=0,sticky=E+W, pady=5)
yournumber1.grid(row=6, column=1, padx=65,sticky=E+W, pady=5)
panel.grid(row=8, column=0, columnspan=2, pady=50)
toolbar.grid(row=10, column=0, columnspan=2)
yes.grid(column =1, row=1)
no.grid(column =2, row=1)
def popup():
top = Toplevel(bg="#ffefd5")
top.title("Koala Encrypter")
popuptitle = Label(top, text="Your password is:", font=Body1, fg="red", bg="#ffefd5")
popuptitle.grid(row = 2,column=0, padx=5, pady = 50,sticky=N+S+E+W)
pwd= Label(top, font=Body2, text="password", bg="#ffefd5", fg= "#00009C", ) #textvariable = newpassword ,
pwd.grid(row= 2, column=1,sticky=E+W,padx=15)
button = Button(top, text="OK", command=top.destroy, relief=RAISED )
button.grid(column =0,columnspan=2, row=4, sticky=N+S+E+W)
def helpmsg():
top = Toplevel(bg="#ffefd5")
top.title("Koala Encrypter")
popuptitle = Label(top, text="Koala series 1.0 - Koala Encrypter", font=Title, bg="#00FA9A", relief=RAISED,)
popuptitle.grid(row = 2,column=0, padx=5, pady = 50,sticky=N+S+E+W)
pwd= Label(top, font=Body, text="Free software to help you keep your acounts safe", bg="#ffefd5")
pwd.grid(row= 1,sticky=E+W,)
Titlems = Label(top, text="Koala Encrypter", font=Title, bg="#00FA9A", relief=RAISED,)
Titlems.grid( row=0, pady=25, sticky=N+S+E+W)
button = Button(top, text="OK", command=top.destroy, relief=RAISED )
button.grid(column =0,columnspan=2, row=4, sticky=N+S+E+W)
max_len = 5
def on_write(*args):
s = website.get()
if len(s) > max_len:
website.set(s[:max_len])
website.trace_variable("w", on_write)
max_len1 = 5
def on_write(*args):
s = passwordvar.get()
if len(s) > max_len1:
passwordvar.set(s[:max_len1])
passwordvar.trace_variable("w", on_write)
max_len2 = 1
def on_write(*args):
s = numbervar.get()
if len(s) > max_len2:
numbervar.set(s[:max_len2])
numbervar.trace_variable("w", on_write)
toolbar = Frame(root)
reset = Button(toolbar, text="Reset", width=6, command=Reset, cursor="cross", relief=RAISED, takefocus=True )
end = Button(toolbar, text="Quit" ,command=root.destroy, relief=RAISED, cursor="X_cursor", takefocus=True)
end.grid(column =3, row=1, sticky=N+S+E+W)
begin = Button(toolbar, text="Start Encrypting", command=start, relief=RAISED, cursor="star",takefocus=True )
begin.grid(column =2, row=1, sticky=N+S+E+W)
confirm = Button(toolbar, text="Next", command =clear_text, cursor="star", relief=RAISED,takefocus=True )
yes = Button(toolbar, text="Yes", command =popup, cursor="star", relief=RAISED,takefocus=True )
no = Button(toolbar, text="No", command =restart, cursor="pirate", relief=RAISED, takefocus=True )
toolbar.grid( row=21, )
menu = Menu(root)
root.config(menu=menu)
filemenu = Menu(menu)
menu.add_cascade(label="File", menu=filemenu)
filemenu.add_command(label="Restart", command=restart)
filemenu.add_separator()
filemenu.add_command(label="Exit", command=root.destroy)
helpmenu = Menu(menu)
menu.add_cascade(label="Help", menu=helpmenu, )
helpmenu.add_command(label="About...", command=helpmsg)
app = root
root.mainloop()
# add functionality, fix validation

To restrict the type/number of characters that can be typed into an entry widget, you can use the entry validatecommand. Here is an example to allow only letters and another one to restrict the entry to 4 digits:
from tkinter import Tk, Entry, Label
def only_letters(action, char):
if action == "1":
# a character is inserted (deletion is 0) allow the insertion
# only if the inserted character char is a letter
return char.isalpha()
else:
# allow deletion
return True
def only_numbers_max_4(action, new_text):
if action == "1":
return new_text.isdigit() and len(new_text) <= 4
else:
return True
root = Tk()
# register validate commands
validate_letter = root.register(only_letters)
validate_nb = root.register(only_numbers_max_4)
Label(root, text="Only letters: ").grid(row=0, column=0)
e1 = Entry(root, validate="key", validatecommand=(validate_letter, '%d', '%S'))
# %d is the action code and %S the inserted/deleted character
e1.grid(row=0, column=1)
Label(root, text="Only numbers, at most 4: ").grid(row=1, column=0)
e2 = Entry(root, validate="key", validatecommand=(validate_nb, '%d', '%P'))
# %P is the new content of the entry after the modification
e2.grid(row=1, column=1)
root.mainloop()
For more details on entry validation, see http://infohost.nmt.edu/tcc/help/pubs/tkinter/web/entry-validation.html

Creating a Tkinter Button to 'clear' Output

I have a very basic program that spits out a string of values, but I am not quite sure how to clear these values. At the moment I have it set up so that I just exit the window and start a new one so that I'm not rewriting over new values all the time. Is there a simple way to add another button that just says something like 'clear' and does exactly that? My code is as below:
def create_widgets(self):
self.entryLabel = Label(self, text="Please enter a list of numbers:")
self.entryLabel.grid(row=0, column=0, columnspan=2)
self.listEntry = Entry(self)
self.listEntry.grid(row=0, column=2, sticky=E)
self.entryLabel = Label(self, text="Please enter an index value:")
self.entryLabel.grid(row=1, column=0, columnspan=2, sticky=E)
self.indexEntry = Entry(self)
self.indexEntry.grid(row=1, column=2)
self.runBttn = Button(self, text="Run Function", command=self.psiFunction)
self.runBttn.grid(row=2, column=0, sticky=W)
self.answerLabel = Label(self, text="Output List:")
self.answerLabel.grid(row=2, column=1, sticky=W)
self.clearBttn = Button(self, text="Clear Output", command=)
self.clearBttn.grid(row=3, column=0, sticky=W)
def clear():
config.self.entryLabel(text="")
tk.Button(text="write", command=write).grid()
tk.Button(text="clear", command=clear).grid()
self.clearBttn = Button(self, text="Clear Output", command=clear)
self.clearBttn.grid(row=3, column=0, sticky=W)

You kinda asked two different questions here. I'll address the first, since that is what you came in with. To change the label, just update its text using the config method:
import Tkinter as tk
root = tk.Tk()
label = tk.Label()
label.grid()
def write():
label.config(text="Blah"*6)
def clear():
label.config(text="")
tk.Button(text="write", command=write).grid()
tk.Button(text="clear", command=clear).grid()
root.mainloop()