Changing the Default Font for all the widgets in Tkinter

In Tkinter applications, you can set a default font that applies to all widgets using the option_add() method. This method allows you to specify global properties like font, background color, and other styling options that all widgets will inherit.

Syntax

window.option_add(pattern, value)

Parameters:

• pattern ? The property pattern (e.g., "*Font", "*Background")
• value ? The value to set for that property

Setting Default Font for All Widgets

Here's how to apply a default font to all widgets in your Tkinter application ?

# Import the required libraries
from tkinter import *

# Create an instance of Tkinter frame
win = Tk()
win.geometry("700x350")

# Add fonts for all the widgets
win.option_add("*Font", "Arial 12")

# Set the font for the Label widget specifically
win.option_add("*Label.Font", "Arial 18 bold")

# Define the background color for all the widgets
win.option_add("*Background", "bisque")

# Display bunch of widgets
Label(win, text="Label").pack(pady=5)
Button(win, text="Button").pack(pady=5)

# Create a Listbox widget
listbox = Listbox(win)
for i in range(5):
    listbox.insert(i, "item %d" % (i+1))
listbox.pack(pady=5)

# Create a Text widget
text_widget = Text(win, width=20, height=5)
text_widget.insert(1.0, "This is a text widget")
text_widget.pack(pady=5)

win.mainloop()

How It Works

The option_add() method uses pattern matching to apply styles:

• "*Font" ? Sets default font for all widgets
• "*Label.Font" ? Sets font specifically for Label widgets
• "*Background" ? Sets background color for all widgets

Customizing Specific Widget Types

from tkinter import *

win = Tk()
win.geometry("600x400")

# Set different fonts for different widget types
win.option_add("*Button.Font", "Helvetica 14 bold")
win.option_add("*Label.Font", "Times 16 italic")
win.option_add("*Text.Font", "Courier 12")

# Create widgets to see the different fonts
Label(win, text="This is a Label").pack(pady=10)
Button(win, text="This is a Button").pack(pady=10)
Text(win, height=3, width=30).pack(pady=10)

win.mainloop()

Key Points

• Use option_add("*Font", "fontname size") to set a global default font
• Specific widget patterns like "*Button.Font" override global settings
• Font specifications can include family, size, and style (bold, italic)
• Changes apply to all widgets created after calling option_add()

Conclusion

The option_add() method provides an efficient way to set consistent styling across all widgets in your Tkinter application. Use global patterns for consistent theming and specific widget patterns for targeted customization.