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Python tkinter window resizes, but widgets never change or move

Python beginner. I placed a scrollbar widget in window and that works, but no matter what I do I can't get the scrollbox widget to change size. Could go with a larger scrollbox or for it to resize when the window resizes, but can't figure out how to force either to happen. Tried lots of different solutions, but feels like the grid and canvas are defaulting to a size and can't figure out how to change that. Help would be appreciated. Code is below:
import tkinter as tk
from tkinter import ttk
import os
import subprocess
class Scrollable(tk.Frame):
"""
Make a frame scrollable with scrollbar on the right.
After adding or removing widgets to the scrollable frame,
call the update() method to refresh the scrollable area.
"""
def __init__(self, frame, width=16):
scrollbar = tk.Scrollbar(frame, width=width)
scrollbar.pack(side=tk.RIGHT, fill=tk.Y, expand=True)
self.canvas = tk.Canvas(frame, yscrollcommand=scrollbar.set)
self.canvas.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)
scrollbar.config(command=self.canvas.yview)
self.canvas.bind('<Configure>', self.__fill_canvas)
# base class initialization
tk.Frame.__init__(self, frame)
# assign this obj (the inner frame) to the windows item of the canvas
self.windows_item = self.canvas.create_window(0,0, window=self, anchor=tk.NW)
def __fill_canvas(self, event):
"Enlarge the windows item to the canvas width"
canvas_width = event.width
self.canvas.itemconfig(self.windows_item, width = canvas_width)
def update(self):
"Update the canvas and the scrollregion"
self.update_idletasks()
self.canvas.config(scrollregion=self.canvas.bbox(self.windows_item))
root = tk.Tk()
root.title("application")
root.geometry('750x800')
dbEnvs = ['a','b']
x = 1
header = ttk.Frame(root)
body = ttk.Frame(root)
footer = ttk.Frame(root)
header.pack(side = "top")
body.pack()
footer.pack(side = "top")
#setup Environment selection
envLabel = tk.Label(header, text="Environment:")
envLabel.grid(row=0,column=0,sticky='nw')
dbselection = tk.StringVar()
scrollable_body = Scrollable(body, width=20)
x = 1
for row in range(50):
checkboxVar = tk.IntVar()
checkbox = ttk.Checkbutton(scrollable_body, text=row, variable=checkboxVar)
checkbox.var = checkboxVar # SAVE VARIABLE
checkbox.grid(row=x, column=1, sticky='w')
x += 1
scrollable_body.update()
#setup buttons on the bottom
pullBtn = tk.Button(footer, text='Pull')
pullBtn.grid(row=x, column=2, sticky='ew')
buildBtn = tk.Button(footer, text='Build')
buildBtn.grid(row=x, column=3, sticky='ew')
compBtn = tk.Button(footer, text='Compare')
compBtn.grid(row=x, column=4, sticky='ew')
root.mainloop()
have tried anchoring, changing the window base size and multiple other things (8 or 19 different items, plus reading lots of posts), but they normally involve packing and since I used grids that normally and ends with more frustration and nothing changed.

If you want the whole scrollbox to expand to fill the body frame, you must instruct pack to do that using the expand and fill options:
body.pack(side="top", fill="both", expand=True)
Another problem is that you're setting expand to True for the scrollbar. That's probably not something you want to do since it means the skinny scrollbar will be allocated more space than is needed. So, remove that attribute or set it to False.
scrollbar.pack(side=tk.RIGHT, fill=tk.Y, expand=False)
tip: when debugging layout problems, the problems are easier to visualize when you temporarily give each widget a unique color. For example, set the canvas to one color, body to another, the instance of Scrollable to another, etc. This will let you see which parts are visible, which are growing or shrinking, which are inside the borders of others, etc.

Tkinter fix size of Frame to not overlap Canvas border with scrollbar

I'm working on a GUI with tkinter and i have a problem.
When i add a scrollbar to my app, the frame on my canvas overlaps the outlines (see image)
Here is the code:
from tkinter import *
window = Tk()
window.geometry("400x225")
scrollbar1 = Scrollbar(window, orient=VERTICAL)
canvas1 = Canvas(window, bg="#003333", yscrollcommand=scrollbar1.set)
frame1 = Frame(canvas1, bg="#003333")
scrollbar1.config(command=canvas1.yview)
scrollbar1.pack(side=RIGHT, fill=Y)
canvas1.pack(fill=BOTH, expand=True)
canvas1.create_window((0, 0), window=frame1, anchor="nw")
for x in range(20):
string = "line " + str(x)
label1 = Label(frame1, fg="white", bg="#003333", text=string, font=("Calibri Bold", 14))
label1.pack(pady=5)
window.update()
canvas1.config(scrollregion=canvas1.bbox("all"))
window.mainloop()
I don't know if it's possible but i want the frame to fit within the canvas and keeping the outlines as well.
I hope you get my problem and can probably help me out! Thanks in advance.

The highlightthickness
Specifies a non-negative value indicating the width of the highlight rectangle to draw around the outside of the widget when it has the input focus.
So, this is not really the "border" that you want. It is a part of the drawing space within the canvas, when you use window_create to draw a window, the parent of that window is the canvas, which begins before the highlight and so the window slides over it.
A solution, as also suggested by #martineau would be to make this 0 by specifying highlightthickness=0 and as you suggested that you need the "border" around the whole thing, you can either create a container frame and specify the bd parameter, or just set the bd of the window window.config(bd=2).

How to dynamically resize window with Tkinter?

root= tk.Tk()
root.title('Quick Googling')
canvas1 = tk.Canvas(root, width = 400, height = 300)
canvas1.pack()
entry1 = tk.Entry (root)
canvas1.create_window(200, 140, window=entry1)
canvas1.config(background="#8FB1CC"
button1 = tk.Button(text='Search Google', bg = "blue")
canvas1.create_window(200, 180, window=button1)
I want the colour of my window and the entry and button to utilise all the space when the window's size is changed.

If you use a frame the geometry mangers of tkinter is doing the job for you see:
import tkinter as tk
root= tk.Tk()
root.title('Quick Googling')
myframe = tk.Frame(root)
myframe.pack(fill='both',expand=True)
entry1 = tk.Entry (myframe,background="#8FB1CC")
entry1.pack(fill='x')
button1 = tk.Button(myframe,text='Search Google', bg = "blue")
button1.pack(fill='both',expand=1)
root.mainloop()
Look on a small overview I wrote over the basics.
fill stretch the slave horizontally, vertically or both expand The
slaves should be expanded to consume extra space in their master.
So what the above code does is to create a frame in its natrual size, this means it shrinks itself to the minimum space that it needs to arrange the children.
After this we use for the first time the geometry manager pack and give the options fill, which tells the frame to stretch and using the optional argument expand to consume extra space. Together they resize your frame with the window, since there is nothing else in it.
After that we create an Entry and using once again the method pack to arrange it with this geometry manager. We are using again the optional argument fill and give the value 'x', which tells the geometry manager to stretch the slave/entry vertically.
So the entry streches vertically if the frame is expandes.
At least we create a Button and using the known keywords, to let it resize with the frame.

My frame is resizing instead of the listbox - tkinter

I'm making a GUI and I'm stuck trying to resize a listbox. The listbox is supposed to expand to fill the frame but instead, the frame shrinks to fit the listbox.
Thanks, in advance, for any help.
I have tried many variations of the code, but none seem to work, so I simplified the code (it still does't work) to put it on here.
import tkinter as tk
w = tk.Tk() # New window
f = tk.Frame(w, width=300, height=500, bg='red') # New frame with specific size
f.grid_propagate(0)
f.grid(row=0, column=0)
lb = tk.Listbox(f, bg='blue') # New listbox
lb.pack(fill=tk.BOTH, expand=True)
I ran these sequentially in IDLE and the frame appears (in red) at the correct size, however, when I pack the listbox, the whole window shrinks to the size of the listbox (and turns completely blue, which is expected).

In my experience, turning off geometry propagation is almost never the right solution. With a couple of decades of using tk and tkinter I've done that only two or three times for very specific edge cases.
Tkinter is very good at making the widget the best size based on the set of widgets you're using. Turning off propagation means you are responsible for doing all calculations to get the window to look right, and your calculations may not be correct when your program runs on a machine with different fonts or a different resolution. Tkinter can handle all of that for you.
Unfortunately, with such a small code example and without knowing your end goal it's hard to solve your layout problems. If your goal is to have a window that is 300x500, the best solution is to make the window that size and then have the frame fill the window, which is easier to do with pack than grid:
import tkinter as tk
w = tk.Tk() # New window
w.geometry("300x500")
f = tk.Frame(w, bg='red') # New frame with specific size
f.pack(fill="both", expand=True)
lb = tk.Listbox(f, bg='blue') # New listbox
lb.pack(fill=tk.BOTH, expand=True)
w.mainloop()

Thank you so much to Tls Chris for your answer and explanation. What I didn't realize is that grid_propagate() and pack_propagate() also affect a widget's children.
Therefore, with the help of Tls Chris, I have fixed my code and it now expands the listbox and doesn't shrink the frame.
Fixed code:
import tkinter as tk
w = tk.Tk() # New window
f = tk.Frame(w, width=300, height=500, bg='red') # New frame
f.grid_propagate(False) # Stopping things (that use grid) resizing the frame
f.pack_propagate(False) # Stopping things (that use pack) resizing the frame
f.grid(row=0, column=0)
lb = tk.Listbox(f, bg='blue') # New listbox
lb.pack(fill=tk.BOTH, expand=True) # Packing the listbox and making it expand and fill the frame

Edit: I think you actually want the listbox to expand to fit the frame. Amended the code to do that as an option
I haven't used pack much but I suspect that grid_propagate changes the behaviour of the grid geometry manager but not of the pack manager.
The below lets app() run with or without propagate set. It uses the grid geometry manager throughout.
import tkinter as tk
def app(propagate = False, expand = False ):
w = tk.Tk() # New window
tk.Label( w, text = 'Propagate: {} \nExpand: {}'.format(propagate, expand) ).grid()
f = tk.Frame(w, width=300, height=500, bg='red') # New frame with specific size
f.grid_propagate(propagate)
f.grid( row=1, column=0 )
lb = tk.Listbox(f, bg='blue') # New listbox
if expand:
f.columnconfigure(0, weight = 1 )
f.rowconfigure(0, weight = 1 )
# lb.pack(fill=tk.BOTH, expand=True)
lb.grid( row=0, column=0, sticky = 'nsew' )
# My guess is that grid_propagate has changed the behaviour of grid, not of pack.
lb.insert(tk.END, 'Test 1', 'Test 2', 'Test 3')
w.mainloop()
This changes the listbox geometry manager to grid. Run app() as below.
app(True, True) # propagate and Expand
app(False, True) # no propagate but expand
app(True, False) # propagate without expand
app() # no propagate or expand

How to set a tkinter window to a constant size

I'm programming a little game with tkinter and briefly, I'm stuck.
I have a kind od starting menu, in which are two buttons and one label.
If I just create the frame everything is fine, it has the size 500x500 pixels
I want the background not to change when I create the buttons and the labe, but it adapts the size whatever I do. Here is my code:
import tkinter as tk
def startgame():
pass
mw = tk.Tk() #Here I tried (1)
mw.title('The game')
back = tk.Frame(master=mw, width=500, height=500, bg='black')
back.pack()
go = tk.Button(master=back, text='Start Game', bg='black', fg='red',
command=lambda:startgame()).pack()
close = tk.Button(master=back, text='Quit', bg='black', fg='red',
command=lambda:quit()).pack()
info = tk.Label(master=back, text='Made by me!', bg='red',
fg='black').pack()
mw.mainloop()
I've searched around on stackoverflow and didn't get anything useful!
I've found just one question a bit similar to mine but the answer didn't work. I tried this:
(1) mw.resizable(width=False, height=False)
I can't imagine what is the problem, I'm really desperate.

You turn off pack_propagate by setting pack_propagate(0)
Turning off pack_propagate here basically says don't let the widgets inside the frame control it's size. So you've set it's width and height to be 500. Turning off propagate stills allows it to be this size without the widgets changing the size of the frame to fill their respective width / heights which is what would happen normally
To turn off resizing the root window, you can set root.resizable(0, 0), where resizing is allowed in the x and y directions respectively.
To set a maxsize to window, as noted in the other answer you can set the maxsize attribute or minsize although you could just set the geometry of the root window and then turn off resizing. A bit more flexible imo.
Whenever you set grid or pack on a widget it will return None. So, if you want to be able to keep a reference to the widget object you shouldn't be setting a variabe to a widget where you're calling grid or pack on it. You should instead set the variable to be the widget Widget(master, ....) and then call pack or grid on the widget instead.
import tkinter as tk
def startgame():
pass
mw = tk.Tk()
#If you have a large number of widgets, like it looks like you will for your
#game you can specify the attributes for all widgets simply like this.
mw.option_add("*Button.Background", "black")
mw.option_add("*Button.Foreground", "red")
mw.title('The game')
#You can set the geometry attribute to change the root windows size
mw.geometry("500x500") #You want the size of the app to be 500x500
mw.resizable(0, 0) #Don't allow resizing in the x or y direction
back = tk.Frame(master=mw,bg='black')
back.pack_propagate(0) #Don't allow the widgets inside to determine the frame's width / height
back.pack(fill=tk.BOTH, expand=1) #Expand the frame to fill the root window
#Changed variables so you don't have these set to None from .pack()
go = tk.Button(master=back, text='Start Game', command=startgame)
go.pack()
close = tk.Button(master=back, text='Quit', command=mw.destroy)
close.pack()
info = tk.Label(master=back, text='Made by me!', bg='red', fg='black')
info.pack()
mw.mainloop()

If you want a window as a whole to have a specific size, you can just give it the size you want with the geometry command. That's really all you need to do.
For example:
mw.geometry("500x500")
Though, you'll also want to make sure that the widgets inside the window resize properly, so change how you add the frame to this:
back.pack(fill="both", expand=True)

Try parent_window.maxsize(x,x); to set the maximum size. It shouldn't get larger even if you set the background, etc.
Edit: use parent_window.minsize(x,x) also to set it to a constant size!

Here is the most simple way.
import tkinter as tk
root = tk.Tk()
root.geometry('200x200')
root.resizable(width=0, height=0)
root.mainloop()
I don't think there is anything to specify.
It's pretty straight forward.

There are 2 solutions for your problem:
Either you set a fixed size of the Tkinter window; mw.geometry('500x500')
OR
Make the Frame adjust to the size of the window automatically;back.place(x = 0, y = 0, relwidth = 1, relheight = 1)
*The second option should be used in place of back.pack()

from tkinter import *
root = Tk()
width = root.winfo_screenwidth() #get your Windows width size
height = root.winfo_screenheight() #get your Windows height size
root.geometry("%dx%d" % (width, height))
root.resizable(False,False)
root.mainloop()
#full size Tkinter