Styling Tkinter Treeview with ttk.Style

Tkinter Treeview is a themed ttk widget, so its appearance is normally controlled through ttk.Style. We can change row colors, fonts, row height, heading appearance and selected-row colors.

For individual rows, Treeview tags provide another level of styling without changing the appearance of the complete widget.

Basic Treeview Style 🔝

Create a ttk.Style object and configure the Treeview style.

from tkinter import ttk

style=ttk.Style()
style.configure('Treeview', background='black', fieldbackground='black', foreground='white')

This default style is used by Treeview widgets that do not specify another style.

Treeview Background and Foreground 🔝

style.configure('Treeview', background='black', fieldbackground='black', foreground='white')

See Tkinter colors for more color values.

Style Treeview Headings 🔝

Column headings use a separate style named Treeview.Heading.

style.configure('Treeview.Heading', background='PowderBlue', foreground='black', font=('Arial', 11, 'bold'))

This changes heading appearance without changing row appearance.

Change Treeview Font 🔝

font1=('Times', 12, 'normal')
style.configure('Treeview', font=font1)

The heading font can be different:

style.configure('Treeview.Heading', font=('Times', 12, 'bold'))

Change Treeview Row Height 🔝

style.configure('Treeview', rowheight=30)

This is useful when Treeview rows use a larger font or images.

Change Selected Row Colors with style.map() 🔝

Selection is a widget state, so use style.map() instead of only style.configure().

style.map('Treeview',
    background=[('selected', 'navy')],
    foreground=[('selected', 'white')])

When the user selects a row, the mapped values are applied.

Create a Custom Style for One Treeview 🔝

If only one Treeview should receive a special appearance, create a named style instead of changing the default Treeview style.

style.configure('Custom.Treeview', background='#202020', fieldbackground='#202020', foreground='white', rowheight=28)
style.configure('Custom.Treeview.Heading', background='PowderBlue', foreground='black', font=('Arial', 11, 'bold'))

tree=ttk.Treeview(root, style='Custom.Treeview')

The naming pattern is important:

Custom.Treeview
Custom.Treeview.Heading

This lets the heading style belong to the same custom Treeview style.

Style Individual Treeview Rows with Tags 🔝

ttk.Style controls the widget, while Treeview tags can style particular items.

tree.tag_configure('high', background='lightgreen', foreground='black')
tree.tag_configure('low', background='mistyrose', foreground='black')

tree.insert('', tk.END, values=(1, 'Alex', 88), tags=('high',))
tree.insert('', tk.END, values=(2, 'Ravi', 35), tags=('low',))

This is useful for highlighting status, marks, warnings or alternating rows.

Alternating Row Colors

tree.tag_configure('even', background='#f2f2f2')
tree.tag_configure('odd', background='white')

for i, row in enumerate(data):
    tag='even' if i%2==0 else 'odd'
    tree.insert('', tk.END, values=row, tags=(tag,))

Change Treeview Style using RadioButtons 🔝

Three Radiobuttons can let the user switch between black, white and yellow Treeview backgrounds.

A StringVar stores the selected color.

color_var=tk.StringVar(value='black')

The update function reads that variable:

def update_style():
    color=color_var.get()

    if color=='black':
        bg, fg='black', 'white'
    elif color=='yellow':
        bg, fg='yellow', 'black'
    else:
        bg, fg='white', 'black'

    style.configure('Custom.Treeview', background=bg, fieldbackground=bg, foreground=fg)

The Radiobuttons can use the same command:

tk.Radiobutton(root, text='Black', variable=color_var, value='black', command=update_style)
tk.Radiobutton(root, text='White', variable=color_var, value='white', command=update_style)
tk.Radiobutton(root, text='Yellow', variable=color_var, value='yellow', command=update_style)

Complete Treeview Style Example 🔝

import tkinter as tk
from tkinter import ttk

def update_style():
    color=color_var.get()

    if color=='black':
        bg, fg='black', 'white'
    elif color=='yellow':
        bg, fg='yellow', 'black'
    else:
        bg, fg='white', 'black'

    style.configure('Custom.Treeview', background=bg, fieldbackground=bg, foreground=fg)

root=tk.Tk()
root.geometry('440x300')
root.title('Treeview Style - plus2net')

style=ttk.Style(root)
style.theme_use('clam')
style.configure('Custom.Treeview', background='black', fieldbackground='black', foreground='white', font=('Times', 12), rowheight=28)
style.configure('Custom.Treeview.Heading', background='PowderBlue', foreground='black', font=('Arial', 11, 'bold'))
style.map('Custom.Treeview', background=[('selected', 'navy')], foreground=[('selected', 'white')])

tree=ttk.Treeview(root, columns=('id', 'name'), show='tree headings', selectmode='browse', height=5, style='Custom.Treeview')
tree.grid(row=0, column=0, columnspan=3, padx=30, pady=20)

tree.column('#0', width=90, anchor='center')
tree.column('id', width=60, anchor='center')
tree.column('name', width=140, anchor='center')

tree.heading('#0', text='Label')
tree.heading('id', text='ID')
tree.heading('name', text='Name')

tree.insert('', tk.END, text='First', values=(1, 'Alex'))
tree.insert('', tk.END, text='Second', values=(2, 'Ravi'))
tree.insert('', tk.END, text='Third', values=(3, 'Ron'))

color_var=tk.StringVar(value='black')

tk.Radiobutton(root, text='Black', variable=color_var, value='black', command=update_style).grid(row=1, column=0)
tk.Radiobutton(root, text='White', variable=color_var, value='white', command=update_style).grid(row=1, column=1)
tk.Radiobutton(root, text='Yellow', variable=color_var, value='yellow', command=update_style).grid(row=1, column=2)

root.mainloop()

ttk Themes and Treeview Styling 🔝

The active ttk theme can influence how styles are rendered.

List Available Themes

print(style.theme_names())

A sample result can include themes such as:

('clam', 'alt', 'default', 'classic')

The exact available themes depend on the operating system and Tcl/Tk installation.

Check the Current Theme

print(style.theme_use())

Use the clam Theme

style.theme_use('clam')

The clam theme is often used in styling examples because custom colors tend to be more predictable than with some operating-system-native themes.

Common Treeview Styling Mistakes 🔝

1. Changing the Default Style when Only One Treeview Should Change

This:

style.configure('Treeview', background='black')

may affect all Treeview widgets using the default style.

Use:

style.configure('Custom.Treeview', background='black')
tree=ttk.Treeview(root, style='Custom.Treeview')

2. Styling Selected Rows with configure()

Selection is a state, so use:

style.map('Custom.Treeview', background=[('selected', 'navy')])

3. Using ttk.Style for One Individual Row

Use Treeview tags instead:

tree.tag_configure('warning', background='yellow')

4. Mixing Heading and Row Styles

Rows use:

Custom.Treeview

Headings use:

Custom.Treeview.Heading

5. Expecting Every Theme to Display Colors Identically

ttk styling is theme-based. Native themes can render some states differently.

6. Using an Invalid show Value

For both the tree column and headings use:

show='tree headings'

Tkinter Treeview Style Summary 🔝

• ttk.Style controls Treeview appearance.
• background controls normal item background.
• fieldbackground controls the Treeview field background.
• foreground controls normal text color.
• Treeview.Heading styles column headings.
• font changes the Treeview row font.
• rowheight controls row height.
• style.map() controls appearance for states such as selected.
• A custom style can be applied to only one Treeview.
• Treeview tags style individual items or groups of rows.
• Radiobuttons can dynamically update Treeview styles.
• The active ttk theme can affect how custom styles are displayed.

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

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