How Does CTKDeb handle StartupWMClass?

[pdschneider]

In my desktop file, I am unable to figure out how to change the StartupWMClass value from "Tk". WM_INFO always returns "Tk" so every one of my apps has to be treated as being in the same app group internally, causing issues. I had a conversation about this with the CustomTkinter dev and he wasn't sure how to resolve it and pointed me here.

That conversation: TomSchimansky/CustomTkinter#2859 (comment)

Does anybody in this community know how to handle this case?

Thanks!

[ibamzjr]

CTkDeb does not need a special option for this; it can emit the standard desktop-entry key. The important part is to make the Tk window class and the desktop entry agree.

Create the root window with an explicit className:

import customtkinter as ctk

app = ctk.CTk(className="MyApp")

CustomTkinter's current CTk constructor forwards Tk arguments such as className (source). Then add the matching key to the CTkDeb configuration:

{
  "desktopEntry": {
    "Name": "My App",
    "StartupWMClass": "MyApp"
  }
}

CTkDeb merges the values in desktopEntry into the generated .desktop file, so the package should contain:

StartupWMClass=MyApp

After rebuilding and reinstalling the package, verify the real value rather than relying on the window title:

xprop WM_CLASS

Click the application window. The class (normally the second string) must match MyApp, including case. If it does not, use the value reported by xprop as StartupWMClass. Changing app.title(...) alone will not change WM_CLASS.

[pdschneider]

Thank you so much! I have my own build flow separate from CTkDeb (although if I had learned about this at the right point I definitely would have used it), but just knowing that I can set className is huge.