How can I set the row height in Tkinter TreeView?

The Treeview widget in Tkinter provides a way to display data in a hierarchical table structure. You can customize the appearance of the Treeview, including setting custom row heights using the ttk.Style configuration.

To set the row height in a Tkinter Treeview, you need to use the ttk.Style() class and configure the rowheight property. This property adds internal padding to each row, making them taller or shorter as needed.

Syntax

style = ttk.Style()
style.configure('Treeview', rowheight=height_value)

Example

Here's how to create a Treeview with custom row height ?

# Import the required libraries
from tkinter import *
from tkinter import ttk

# Create an instance of tkinter frame
win = Tk()

# Set the size of the tkinter window
win.geometry("700x350")

# Create a style object and set theme
style = ttk.Style()
style.theme_use('clam')

# Configure the row height (40 pixels)
style.configure('Treeview', rowheight=40)

# Create a Treeview widget
tree = ttk.Treeview(win, columns=("c1", "c2", "c3"), show='headings', height=5)

# Configure columns
tree.column("c1", anchor=CENTER, width=100)
tree.heading("c1", text="ID")
tree.column("c2", anchor=CENTER, width=150)  
tree.heading("c2", text="First Name")
tree.column("c3", anchor=CENTER, width=150)
tree.heading("c3", text="Last Name")

# Insert sample data
tree.insert('', 'end', values=('1', 'John', 'Smith'))
tree.insert('', 'end', values=('2', 'Emily', 'Johnson'))
tree.insert('', 'end', values=('3', 'Michael', 'Brown'))
tree.insert('', 'end', values=('4', 'Sarah', 'Davis'))
tree.insert('', 'end', values=('5', 'David', 'Wilson'))

tree.pack(pady=20)

win.mainloop()

Key Parameters

Different Row Heights

You can experiment with different row heights to find what works best for your application ?

from tkinter import *
from tkinter import ttk

win = Tk()
win.geometry("800x400")

# Create style object
style = ttk.Style()
style.theme_use('clam')

# Try different row heights
heights = [20, 30, 50]

for i, height in enumerate(heights):
    # Configure different row height for each treeview
    style_name = f'Custom{i}.Treeview'
    style.configure(style_name, rowheight=height)
    
    # Create treeview with custom style
    tree = ttk.Treeview(win, columns=("data",), show='headings', height=3, style=style_name)
    tree.heading("data", text=f"Row Height: {height}px")
    tree.column("data", anchor=CENTER, width=200)
    
    # Add sample data
    tree.insert('', 'end', values=(f'Row 1 - Height {height}',))
    tree.insert('', 'end', values=(f'Row 2 - Height {height}',))
    tree.insert('', 'end', values=(f'Row 3 - Height {height}',))
    
    tree.pack(pady=10)

win.mainloop()

Output

Running the first example will display a Treeview with rows that are 40 pixels tall, providing more space for the data and improving readability.

Conclusion

Use ttk.Style().configure('Treeview', rowheight=value) to set custom row heights in Tkinter Treeview widgets. This improves readability and allows better accommodation of larger text or icons within table cells.