I am trying to add a launcher icon for a custom Python script showing a Tkinter window (script location: /home/hakon/my-tkapp.py):

#! /usr/bin/env python3
import tkinter as tk
root = tk.Tk(className='MyTkApp')
label = tk.Label(root, text="Hello World")

The script is executable. I am using pyenv, so if I run the following from gnome-terminal:

$ which python3

I created a desktop file (file location: ~/.local/share/applications/my-tk-app.desktop):

[Desktop Entry]
Name=My Tk Application

For the icon, I just (for the purpose of testing) copied one of the standard icons:

cp /usr/share/icons/hicolor/48/apps/apport.png /home/hakon/icons/my-tk-app-icon.png

Running the desktop-file-validate command on the desktop file gives no output, so the desktop file should be OK.

However, when I run the python script from the terminal:


I still get the generic question mark icon in the launcher.

What am I overlooking here?


Due to the fact that your question is nicely documented, we can find the problem :)

  • In your application, you set:

    root = tk.Tk(className='MyTkApp')
  • Now if you open a terminal, type:

    $ xprop WM_CLASS

    and subsequently click on the window of your application, it shows:

    WM_CLASS(STRING) = "myTkApp", "Mytkapp"

This is just not the same as the window class you set; the capitals are different. The only conclusion is that for some reason, the window class (capital-format) you set is not accepted by the window manager.

When I changed your launcher to match myTkApp:


it works fine (for convenience reason, I set the firefox icon, since I don't have your icon):

[Desktop Entry]
Name=My Tk Application

The result:

enter image description here

  • Hi Jacob, now I got another problem that I think is related to tkinter, see this question – Håkon Hægland Jun 28 '17 at 7:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.