How to center a tkinter widget in a sticky frame

The problem is that none of your columns have any weight. It is the weight attribute that decides what columns (and rows) get any extra space. Since none of your columns have a non-zero weight, none of the extra space is allocated to them, so they stay as small as they can be.

As a rule of thumb, you should always give at least one row and one column in a frame a non-zero weight. In your case, giving row 0 and column 0 a weight of 1 for all of the frames seems to work:

self.root.grid_columnconfigure(0, weight=1)self.root.grid_rowconfigure(0, weight=1)self.contentFrame.grid_columnconfigure(0, weight=1)self.contentFrame.grid_rowconfigure(0, weight=1)self.topBar.grid_columnconfigure(0, weight=1)self.topBar.grid_rowconfigure(0, weight=1)

by using 'how to make tkinter grid expand' in google i came across the problem.

quote from Bryan Oakley

Rows and columns have "weight" which describes how they grow or shrink to fill extra space >in the master. By default a row or column has a weight of zero, which means you've told the >label to fill the column but you haven't told the column to fill the master frame.

To fix this, give the column a weight.

class Test():    def __init__(self,root):        self.root = root        self.root.columnconfigure(0, weight=1)        self.root.config(bg='green')        self.message = 'test message'        self.contentFrame = Frame(self.root)        self.contentFrame.config(background='black',borderwidth=5,relief ='sunken')        self.contentFrame.grid(row=0, column=0, sticky='news')        self.contentFrame.columnconfigure(0, weight=1)        self.topBar = Frame(self.contentFrame, border=2, relief=RAISED)        self.topBar.grid(row=0, column=0, columnspan=23,sticky=W+E)        self.topBar.config(background='blue')        self.topBar.columnconfigure(0, weight=1)        self.newGameButton = Button(self.topBar, text="New Game")        self.newGameButton.grid(row=0, column=0)        self.newGameButton.config(background='red')        self.messageBox = Label(self.topBar, text=self.message, height=2)        self.messageBox.grid(row=1, column=0, columnspan=1,sticky=W+E)        self.messageBox.config(background='yellow')Test(root)