如何以较小的增量 (Python) 更改 Tkinter 小部件的宽度？

Question

The left side of the box is aligned with the left side of some_label . I am unable to set the width so that the right side of some_label also aligns with the right side of the box because the increments between different width values are too large. A width of 35 puts the right end of some_label too far left and a width of 36 puts it too far right.

from tkinter import *
root = Tk()

root.geometry('500x500')

box = Frame(root, width=383, height=246, bg='black')

box.place(x=241, y=65, anchor=CENTER)

some_label = Label(root, text='Some Label', borderwidth=1, relief='solid')

some_label.place(x=50, y=210)

some_label.config(width=35, font=('TkDefaultFont', 15))  # whether width is 35 or 36, the label never aligns with the box

mainloop()

Answer 1

Since you use place() , you can specify the width directly:

import tkinter as tk

root = tk.Tk()
root.geometry('500x500')

box = tk.Frame(root, width=383, height=246, bg='black')
box.place(x=241, y=65, anchor='c')

some_label = tk.Label(root, text='Some Label', borderwidth=1, relief='solid')
some_label.place(x=241, y=210, width=383, anchor='c') # set width to same as 'box'
some_label.config(font=('TkDefaultFont', 15))

root.mainloop()

Answer 2

To set the width of a Label in pixels you have to include an image. Easiest would to use a transparent pixel and present it in the label with compound='center' which does not offset the text.

Alternatively you could simply use a containing frame to control the widget sizes.

I have included both ways in my example.

from tkinter import *

root = Tk()
root.geometry('500x500')

box = Frame(root, width=383, height=246, bg='black')
box.place(x=241, y=65, anchor=CENTER)

some_label = Label(root, text='Some Label', borderwidth=1, relief='solid')
some_label.place(x=50, y=210)
img = PhotoImage(file='images/pixel.gif')       # Create image
some_label.config(image=img, compound='center') # Set image in label
some_label.config(width=379, font=('TkDefaultFont', 15))    # Size in pixels

# Alternateivly control size by an containing widget:
container = Frame(root, bg='tan')   # Let frame adjust to contained widgets
container.place(x=241, y=360, anchor=CENTER)
# Let the contained widget set width
other_box = Frame(container, height=100, width=383, bg='black') # Set width
other_box.pack()
other_label = Label(container, text='Some Label', borderwidth=1, relief='solid')
other_label.pack(expand=True, fill=X, pady=(20,0))  # Expand to fill container
other_label.config(font=('TkDefaultFont', 15))

mainloop()

If you are going to make complex GUI designs, grid() is almost always easier to use.