Border colours of canvases (tkinter)

Question

I need help with changing the border colour of a canvas in tkinter

This is my code:

w = int(root.winfo_screenwidth())
loader = Canvas(width=w, height=20, bd=1)
loader.grid(column=0, row=1)

I have tried:

fill="black"
outline="black"
bd="black"

Answer 1

You can use highlightbackground option to change color of border highlight ring(which is also a border-like thing, but is separate from the actual border). (correction, thanks to Bryan Oakley's comment )

To change border highlight ring thickness, you should use highlightthickness option.

loader = Canvas(..., highlightthickness=1, highlightbackground="black")

Also, if you want to remove that border highlight ring , you can set highlightthickness to 0.

loader = Canvas(..., highlightthickness=0)

Answer 2

tkinter Canvas allows TWO borders ( Python 3.9 tkinter.TkVersion 8.6 )

A 'normal' border and a highlight border. To change their color and thickness properties set the bd, bg, highlightthickness and highlightbackground named parameter:

obj_tkinter_Canvas = tkinter.Canvas( ..., 
    bd = 2
    bg = 'white'
    highlightthickness  = 1, 
    highlightbackground = 'white'
)

The integers are border thicknesses in pixels. The background colors are set using symbolic names ( see for example https://www.tcl.tk/man/tcl8.4/TkCmd/colors.html for a list of available color names ).