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Python Tkimport how to make one from several windows when importing from a module?

I am writing an application in tkinter consisting of several modules in which there are classes. Each module to a separate page of the app. As I move the buttons between the pages "next", "previous" it opens a new window for me every time. How do I make it so that each time calling pages opens in the same window?
I give draft code.
thank you for your help :D
task1.py
import tkinter as tk
from Test.modul.task1 import FirstPage1
class FirstPage0:
def __init__(self, root):
self.root = root
def get_settings(self):
# Window settings
self.root.geometry("100x200")
def get_second_page(self):
FirstPage1(tk.Toplevel()).get_run_first_page()
def get_button(self):
# Add buttons
tk.Button(self.root, text="Start page", command=self.get_second_page).pack()
tk.Button(self.root, text="Exit", command=self.root.destroy).pack()
def get_run_first_page(self):
# Launching the application
self.get_settings()
self.get_button()
self.root.mainloop()
if __name__ == '__main__':
first = FirstPage0(tk.Tk())
first.get_run_first_page()
task2.py
import tkinter as tk
class FirstPage1:
def __init__(self, root):
self.root = root
def get_settings(self):
# Window settings
self.root.geometry("100x200")
def get_second_page1(self):
from Test.task import FirstPage0
FirstPage0(tk.Toplevel()).get_run_first_page()
def get_button(self):
# Add buttons
tk.Button(self.root, text="Back", command=self.get_second_page1).pack()
tk.Button(self.root, text="Exit", command=self.root.destroy).pack()
def get_run_first_page(self):
# Launching the application
self.get_settings()
self.get_button()
self.root.mainloop()
if __name__ == '__main__':
first = FirstPage1(tk.Tk())
first.get_run_first_page()

Solution
#AdrianSz, you wanted to make the buttons not stack under each other. There are three ways to do so. One, is to keep only one button and change its command and text parameters each time when the frames change. Another would be to unpack the button not needed and pack the button needed. The third would be to pack the buttons in the root window instead of frame and change the text and command parameters. I would recommend the second method as it is easier and less prone to errors.
Code
task1.py
import tkinter as tk
from Test.modul.task1 import FirstPage1
class FirstPage0:
def __init__(self, root):
self.root = root
def get_settings(self):
# Window settings
self.root.geometry("100x200")
def get_second_page(self):
self.root.pg_0_btn_start.pack_forget()
self.root_pg_0_btn_exit.pack_forget()
FirstPage1(tk.Toplevel()).get_run_first_page()
def get_button(self):
# Add buttons
self.root.pg_0_btn_start = tk.Button(self.root, text="Start page",
command=self.get_second_page).pack()
self.root_pg_0_btn_exit = tk.Button(self.root, text="Exit",
command=self.root.destroy).pack()
def get_run_first_page(self):
# Launching the application
self.get_settings()
self.get_button()
self.root.mainloop()
if __name__ == '__main__':
first = FirstPage0(tk.Tk())
first.get_run_first_page()
task2.py
import tkinter as tk
class FirstPage1:
def __init__(self, root):
self.root = root
def get_settings(self):
# Window settings
self.root.geometry("100x200")
def get_second_page1(self):
from Test.task import FirstPage0
self.root.pg_1_btn_back.pack_forget()
self.root_pg_1_btn_exit.pack_forget()
FirstPage0(tk.Toplevel()).get_run_first_page()
def get_button(self):
# Add buttons
self.root.pg_1_btn_back = tk.Button(self.root, text="Back", command=self.get_second_page1).pack()
self.root.pg_1_btn_exit = tk.Button(self.root, text="Exit", command=self.root.destroy).pack()
def get_run_first_page(self):
# Launching the application
self.get_settings()
self.get_button()
self.root.mainloop()
if __name__ == '__main__':
first = FirstPage1(tk.Tk())
first.get_run_first_page()
Note: I couldn't test this code from my side so if there are any errors, please comment on this answer
Suggestions
Since you are using modules for these, just make them inherit a class specified in a different file and operate them both from that file. There you can use self to access the methods of a subclass because the subclasses instantiate the base class and thus the self is a object of the subclass and is passed to the base class. The type of code you used is quite confusing too. I have added code to give you your wanted output using the principles I mentioned here. Hope this helped!

Using super() on tk.TopLevel, but do not generate second window?

I am attempting to implement a trivial MVC application.
When super().__init__() is called, two windows are generated in my python application.
What is the appropriate usage when attempting to inherit from tk.TopLevel, when I only want to generate one window?
import tkinter as tk
from tkinter import ttk
class View(tk.Toplevel):
def __init__(self, controller):
super().__init__()
self.controller = controller
def exec_main(self):
self.mainloop()
class Controller:
def __init__(self):
self.view = View(self)
if __name__ == '__main__':
app = Controller()
app.view.exec_main()
Doing something like super().__init__(master=self) or super().__init__(self) does not seem to be the solution.
An alternative approach would be to do something like this for the main:
import tkinter as tk
class View(tk.Toplevel):
def __init__(self, master):
tk.Toplevel.__init__(self, master)
class Controller:
def __init__(self, root):
self.view = View(root)
if __name__ == '__main__':
root = tk.Tk()
root.withdraw()
app = Controller(root)
root.mainloop()
But this seems wasteful.

Without exception, every widget except the root window requires a parent. If you don't create a root window then one will be created for you. When you create an instance of Toplevel and call super().__init__(), if you don't have a root window then tkinter will create one for you.
As you've observed, the correct workaround is to explicitly create a root window and then hide it. You have to make sure to give the user a way to destroy this root window since it won't automatically be destroyed when you close the Toplevel windows.

I get the error _tkinter.TclError: bad window path name ".!button" when I destroy the button

from tkinter import *
master=Tk()
class check:
def __init__(self,root):
self.root=root
self.b1=Button(root,text="Click me",command=self.undo)
self.b2=Button(root,text="Again",command=self.click)
def click(self):
self.b1.place(relx=0.5,rely=0.5)
def undo(self):
self.b1.destroy()
self.b2.place(relx=0.2,rely=0.2)
c=check(master)
c.click()
master.mainloop()
This is my code. I get _tkinter.TclError: bad window path name ".!button" error only when I use destroy method. But I want to delete previous button when another button appears.What should I do?

What are you doing? When you click the "Click me" button (and call the self.undo method, where the self.b1 button is destroyed) and then click the "Again" button (and call the self.click method, which tries to place already destroyed self.b1 button), you get the error, that the button does not exist. Of course, it doesn't because you have destroyed it.
It looks like you meant to hide the button. If you intended to do this, then you could just use .place_forget() method (there are also .pack_forget() and .grid_forget() methods for pack and grid window managers, respectively), that hides the widget, but not destroys it, and hence you would be able to restore it again when you need.
Here is your fixed code:
from tkinter import *
master = Tk()
class check:
def __init__(self, root):
self.root = root
self.b1 = Button(root, text="Click me", command=self.undo)
self.b2 = Button(root, text="Again", command=self.click)
def click(self):
self.b2.place_forget()
self.b1.place(relx=0.5, rely=0.5)
def undo(self):
self.b1.place_forget()
self.b2.place(relx=0.2, rely=0.2)
c = check(master)
c.click()
master.mainloop()
I can also give you a piece of advice about the implementation:
1) You should write the code according to the PEP8 style; classes should be named in the CamelCase.
2) You should inherit your Tkinter app class(es) either from Tk (usage is shown below) Toplevel(the same as Tk, but use ONLY for child windows), Frame class (almost the same as for Tk, but you need to pack/grid/place that Frame in a window).
3) It's better to create the widgets in a separate function (it helps while developing complex and big apps).
4) It's recommended to write if __name__ == "__main__": condition before creating the window (if you do like this, you will be able to import this code from other modules, and the window won't open in that case).
Here is an example:
from tkinter import *
class Check(Tk):
def __init__(self):
super().__init__()
self.create_widgets()
self.click()
def create_widgets(self):
self.b1 = Button(self, text="Click me", command=self.undo)
self.b2 = Button(self, text="Again", command=self.click)
def click(self):
self.b2.place_forget()
self.b1.place(relx=0.5, rely=0.5)
def undo(self):
self.b1.place_forget()
self.b2.place(relx=0.2, rely=0.2)
if __name__ == "__main__":
Check().mainloop()

After you destroyed button b1 in the undo(self) function tkinter cannot access it anymore and will be confused when you try to place is somewhere in the click(self) function.
To make button b1 only disappear visually you could place it outside of the window instead of destroying it. To do so replace
self.b1.destroy()
with
self.b1.place(relx=-5, rely=0)
This will move the button b1 far to the left, where it cannot be seen.
When calling the click(self) function, the button will reappear, because it will be moved inside the window again.

Tkinter newly created button does not execute command

A script should open an application with two buttons visible. When Hello button is pressed a new button is gridded into the row number 1 and Hello button to be deactivated. When this new button is pressed it should delete itself off the grid and reactivate hello button but it does not do it.
Please check the video to see it in action.
Code edited to comment suggestion
from tkinter import *
class Application(Frame):
def __init__(self, master=None):
self.master = master
self.master.geometry('300x100+10+10')
Frame.__init__(self, master)
self.pack()
self.createWidgets()
def new_button(self):
print("enable_b")
self.hi_there.config(state=ACTIVE)
self.new_button.grid_remove()
def say_hi(self):
print("hi there, everyone!")
self.new_button = Button(self)
self.new_button.config(text = "New BTN", command=self.new_button)
self.new_button.grid(row=1,column=0)
self.hi_there.config(state=DISABLED)
def createWidgets(self):
self.QUIT = Button(self)
self.QUIT.config(text="QUIT",fg="red",command=self.quit)
self.QUIT.grid(row=0,column=1)
self.hi_there = Button(self)
self.hi_there["text"] = "Hello",
self.hi_there["command"] = self.say_hi
self.hi_there.grid(row=0,column=0)
def quit(self):
self.master.destroy()
def testit():
root = Tk()
app = Application(master=root)
app.mainloop()
if __name__ == '__main__':
testit()

Initially, self.new_button refers to a method. Then, you do this:
self.new_button = Button(self)
That effecting removes the method and replaces it with the button widget itself.
Also, you never assign a command to the new button, so clicking it doesn't cause anything to be called.

Where your program will technically work just fine with the 2 correction mentioned in Bryan's answer I am not sure why you are taking all the extra effort configuring the widgets for each individual field. All your configs can be done when you create the widget.
That said you can also change a few things for a cleaner code and 1 change I think that really needs to be made is how you are removing the new_button from the grid. When you do grid_remove() this only takes the widget off the screen but does not get rid of the widget. Then next time you press the say_hi button you will end up creating a new button and the old button will still exist. Instead I think I would use destroy() on the button and then let say_hi recreate it.
See this revised version of your code. You will see what I mean about configuring everything when creating the widget and also you do not need to write your own function for quit you can simply do self.master.destroy in the quit button command.
import tkinter as tk
class Application(tk.Frame):
def __init__(self, master=None):
tk.Frame.__init__(self, master)
self.master = master
self.master.geometry('300x100+10+10')
self.create_widgets()
def new_btn(self):
print("enable_b")
self.hi_there.config(state="active")
self.new_button.destroy()
def say_hi(self):
print("hi there, everyone!")
self.new_button = tk.Button(self, text="New BTN", command=self.new_btn)
self.new_button.grid(row=1, column=0)
self.hi_there.config(state="disabled")
def create_widgets(self):
tk.Button(self, text="QUIT", fg="red", command=self.master.destroy).grid(row=0,column=1)
self.hi_there = tk.Button(self, text="Hello", command=self.say_hi)
self.hi_there.grid(row=0, column=0)
if __name__ == '__main__':
root = tk.Tk()
app = Application(master=root).pack()
root.mainloop()

Using Tkinter in python to edit the title bar

I am trying to add a custom title to a window but I am having troubles with it. I know my code isn't right but when I run it, it creates 2 windows instead, one with just the title tk and another bigger window with "Simple Prog". How do I make it so that the tk window has the title "Simple Prog" instead of having a new additional window. I dont think I'm suppose to have the Tk() part because when i have that in my complete code, there's an error
from tkinter import Tk, Button, Frame, Entry, END
class ABC(Frame):
def __init__(self,parent=None):
Frame.__init__(self,parent)
self.parent = parent
self.pack()
ABC.make_widgets(self)
def make_widgets(self):
self.root = Tk()
self.root.title("Simple Prog")

If you don't create a root window, Tkinter will create one for you when you try to create any other widget. Thus, in your __init__, because you haven't yet created a root window when you initialize the frame, Tkinter will create one for you. Then, you call make_widgets which creates a second root window. That is why you are seeing two windows.
A well-written Tkinter program should always explicitly create a root window before creating any other widgets.
When you modify your code to explicitly create the root window, you'll end up with one window with the expected title.
Example:
from tkinter import Tk, Button, Frame, Entry, END
class ABC(Frame):
def __init__(self,parent=None):
Frame.__init__(self,parent)
self.parent = parent
self.pack()
self.make_widgets()
def make_widgets(self):
# don't assume that self.parent is a root window.
# instead, call `winfo_toplevel to get the root window
self.winfo_toplevel().title("Simple Prog")
# this adds something to the frame, otherwise the default
# size of the window will be very small
label = Entry(self)
label.pack(side="top", fill="x")
root = Tk()
abc = ABC(root)
root.mainloop()
Also note the use of self.make_widgets() rather than ABC.make_widgets(self). While both end up doing the same thing, the former is the proper way to call the function.

Here it is nice and simple.
root = tkinter.Tk()
root.title('My Title')
root is the window you create and root.title() sets the title of that window.

Try something like:
from tkinter import Tk, Button, Frame, Entry, END
class ABC(Frame):
def __init__(self, master=None):
Frame.__init__(self, master)
self.pack()
root = Tk()
app = ABC(master=root)
app.master.title("Simple Prog")
app.mainloop()
root.destroy()
Now you should have a frame with a title, then afterwards you can add windows for
different widgets if you like.

One point that must be stressed out is:
The .title() method must go before the .mainloop()
Example:
from tkinter import *
# Instantiating/Creating the object
main_menu = Tk()
# Set title
main_menu.title("Hello World")
# Infinite loop
main_menu.mainloop()
Otherwise, this error might occur:
File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/tkinter/__init__.py", line 2217, in wm_title
return self.tk.call('wm', 'title', self._w, string)
_tkinter.TclError: can't invoke "wm" command: application has been destroyed
And the title won't show up on the top frame.

Example of python GUI
Here is an example:
from tkinter import *;
screen = Tk();
screen.geometry("370x420"); //size of screen
Change the name of window
screen.title('Title Name')
Run it:
screen.mainloop();

I found this works:
window = Tk()
window.title('Window')
Maybe this helps?

Easy method:
root = Tk()
root.title('Hello World')

Having just done this myself you can do it this way:
from tkinter import Tk, Button, Frame, Entry, END
class ABC(Frame):
def __init__(self, parent=None):
Frame.__init__(self, parent)
self.parent = parent
self.pack()
ABC.make_widgets(self)
def make_widgets(self):
self.parent.title("Simple Prog")
You will see the title change, and you won't get two windows. I've left my parent as master as in the Tkinter reference stuff in the python library documentation.

For anybody who runs into the issue of having two windows open and runs across this question, here is how I stumbled upon a solution:
The reason the code in this question is producing two windows is because
Frame.__init__(self, parent)
is being run before
self.root = Tk()
The simple fix is to run Tk() before running Frame.__init__():
self.root = Tk()
Frame.__init__(self, parent)
Why that is the case, I'm not entirely sure.

self.parent is a reference to the actual window, so self.root.title should be self.parent.title, and self.root shouldn't exist.

widget.winfo_toplevel().title("My_Title")
changes the title of either Tk or Toplevel instance that the widget is a child of.

I found a solution that should help you:
from tkinter import Tk, Button, Frame, Entry, END
class ABC(Frame):
def __init__(self,master=None):
super().__init__(master)
self.pack()
self.master.title("Simple Prog")
self.make_widgets()
def make_widgets(self):
pass
root = Tk()
app = ABC(master=root)
app.mainloop()
Found at: docs.python.org