Tkinter Treeview background tag not working

Question

Trying to colorize different rows in a Tkinter Treeview. I have gone through multiple docs and tutorials and believe I am doing it correctly (even tried variations like tags=("1",)) but nothing seems to work. Any help is appreciated.

import tkinter
from tkinter import ttk

mainWindow = tkinter.Tk()

tree = ttk.Treeview(mainWindow, height=8, column=['', '', '', '', ''])
tree.grid(row=2, column=0, columnspan=2)
tree.heading('#0', text='Numer')
tree.column('#0', width=150)
tree.heading('#1', text='Two')
tree.column('#1', width=200)
tree.heading('#2', text='Three')
tree.column('#2', width=200)
tree.heading('#3', text='Four')
tree.column('#3', width=80)
tree.heading('#4', text='Five')
tree.column('#4', width=40, stretch=False)
tree.tag_configure("1", background='green') 
tree.tag_configure("2", background='#FF6666')
tree.tag_configure("3", background='#FFFF99')

tree.insert('', 'end', text="One", values=("2", "3", "4", "5"), tags="1")
tree.insert('', 'end', text="Two", values=("2", "3", "4", "5"), tags="2")
tree.insert('', 'end', text="Three", values=("2", "3", "4", "5"), tags="3")
tree.insert('', 'end', text="Four", values=("2", "3", "4", "5"), tags="1")
tree.insert('', 'end', text="Five", values=("2", "3", "4", "5"), tags="1")

mainWindow.mainloop()

Answer 1

Treeview styling was broken in Tkinter 8.6.9. Issue is marked as resolved, but for Tkinter 8.6.9 you can use a following workaround, by including it before your Treeview initialization:

def fixed_map(option):
    # Fix for setting text colour for Tkinter 8.6.9
    # From: https://core.tcl.tk/tk/info/509cafafae
    #
    # Returns the style map for 'option' with any styles starting with
    # ('!disabled', '!selected', ...) filtered out.

    # style.map() returns an empty list for missing options, so this
    # should be future-safe.
    return [elm for elm in style.map('Treeview', query_opt=option) if
      elm[:2] != ('!disabled', '!selected')]

style = ttk.Style()
style.map('Treeview', foreground=fixed_map('foreground'),
  background=fixed_map('background'))

Answer 2

I had the same problem with treeview using python 3.9 in windows 10. Tag.configure was working properly on linux but was not painting the colors according to the tags in windows. I found the solution in codemy Youtube channel. Under windows you have to apply a style, like this:

# your imports
style=ttk.Style()
style.theme_use("default")
style.configure("Treeview", background="lightgrey",rowheight=25)
style.configure("TFont", family="Helvetica", size="10")

def ...():
    ...
    style.configure("Treeview", background="white")
    style.map("Treeview",background=[("selected","lightblue")])
    tvLista = ttk.Treeview(frDadosC2,columns=("1","2","3","4","5","6"),height=39, show='headings')
    tvLista.tag_configure('laranja', background='#FFE5CC')

Using the above solution your tag.configure will work accordingly.