How to make the ttk treeview not show extra empty columns?

Question

I am building an app with tkinter and running into some annoying issues.

When I load my data into the ttk treeview, I see that there are always some additional columns on the right side of my treeview which are empty. I realized for a bigger data set there are many more columns which are empty (actual data is loaded correctly). I want to get rid of these extra columns or know the source of this. I have attached a code sample below to show the issue.

I would also like to create a column selection functionality but unless the above issue is solved I don't feel like moving forward with it. Is there a simple solution to get rid of the empty columns? is column selection possible out of the box? The idea is to have a little bit excel kind of functionality but not too elaborate.

import pandas as pd
import tkinter as tk
from tkinter import ttk
from tkinter.messagebox import showinfo

root = tk.Tk()
root.title('Treeview demo')
root.geometry('620x200')

data = {'Name':['Tom', 'nick', 'krish', 'jack', 'mack', 'tack', 'crack', 'lack'], 
        'Age':[20, 21, 19, 18, 20, 21, 19, 18]}

df = pd.DataFrame(data)

tree = ttk.Treeview(root, columns=df.columns, show='headings')
scrollbar_y = ttk.Scrollbar(root, command=tree.yview)
scrollbar_x = ttk.Scrollbar(root, command=tree.xview,
                                    orient=tk.HORIZONTAL)
tree.config(xscrollcommand=scrollbar_x.set, yscrollcommand=scrollbar_y.set)
scrollbar_y.pack(fill=tk.Y, side=tk.RIGHT)
scrollbar_x.pack(fill=tk.X, side=tk.BOTTOM)
tree.pack(fill="both", expand=True)

df.dropna(axis=1, how='all', inplace=True)

df.columns = [str(x)[:50] for x in df.columns]
df = df.reset_index(drop=True)

print("all cols : ", df.columns)

print(df.columns)

# display the data in the treeview.
df_list = list(df.columns)
df_reset = df.to_numpy().tolist()

print("No of columns ", len(df_list))

tree["columns"] = df.columns

for i in range(len(df_list)):
    col = df_list[i]
    tree.column(i, anchor='c')
    tree.heading(i, text=col)

j = 0
for dt in df_reset:
    v = [r for r in dt]
    print("v ", v)
    tree.insert('', 'end', iid=j, values=v)
    j += 1
print("Total rows : ", j)

root.mainloop()

Thanks for your suggestions in advance!

Edit: fixed the typo in instantiation of treeview to df.columns as suggested. In the real code I Instantiate an empty tree and later on populate it with content and set columns using

tree["columns"] = df.columns.

Answer 1

If you print out tree["columns"] after tree["columns"] = df.columns, you will get:

("Index(['Name',", "'Age'],", "dtype='object')")

So you actually configure the treeview to have three columns instead of two.

You need to convert df.columns to list:

tree["columns"] = df.columns.to_list()

Or simply use df_list (result of converting df.columns to list) instead of df.columns:

tree["columns"] = df_list

And the result of your code:

Answer 2

You need to use the actual column names df.columns instead of numerical indices to configure the Treeview. This ensures proper alignment between the DataFrame columns and the Treeview, preventing the appearance of extra empty columns.

import pandas as pd
import tkinter as tk
from tkinter import ttk

root = tk.Tk()
root.title('Treeview demo')
root.geometry('620x200')

data = {'Name': ['Tom', 'Nick', 'Krish', 'Jack', 'Mack', 'Tack', 'Crack', 'Lack'], 
        'Age': [20, 21, 19, 18, 20, 21, 19, 18],
        'City': ['NY', 'LA', 'SF', 'CHI', 'HOU', 'DAL', 'SEA', 'ATL']}
df = pd.DataFrame(data)

tree = ttk.Treeview(root, show='headings')
scrollbar_y = ttk.Scrollbar(root, command=tree.yview)
scrollbar_x = ttk.Scrollbar(root, command=tree.xview, orient=tk.HORIZONTAL)
tree.config(xscrollcommand=scrollbar_x.set, yscrollcommand=scrollbar_y.set)

scrollbar_y.pack(fill=tk.Y, side=tk.RIGHT)
scrollbar_x.pack(fill=tk.X, side=tk.BOTTOM)
tree.pack(fill="both", expand=True)

columns = list(df.columns)
tree["columns"] = columns

for col in columns:
    tree.column(col, anchor='c')
    tree.heading(col, text=col)

for index, row in df.iterrows():
    tree.insert('', 'end', values=row.tolist())

def toggle_column(col):
    if tree.heading(col, option="text") == "":
        tree.heading(col, text=col)
        tree.column(col, width=100)
    else:
        tree.heading(col, text="")
        tree.column(col, width=0)

menu = tk.Menu(root)
root.config(menu=menu)
columns_menu = tk.Menu(menu, tearoff=0)
menu.add_cascade(label="Columns", menu=columns_menu)

for col in columns:
    columns_menu.add_command(label=col, command=lambda c=col: toggle_column(c))

root.mainloop()