Linux - Ubuntu AppImage Desktop Application Menu Setup

What is an AppImage?

• AppImage is a universal software packaging format for Linux.
• It allows developers to distribute portable applications that run on most Linux distributions without installation or root permissions.
• Each AppImage bundles the application and all its dependencies into a single executable file.
• Benefits of AppImages:
  • No installation required: just download, make executable, and run.
  • No need for root access.
  • Easy to remove: just delete the file.

The Application Menu Issue

• By default, AppImages are launched by double-clicking the file or running it from the terminal.
• However, this isn’t as seamless as launching applications installed via your package manager, which appear in your desktop environment’s application menu (Dash, Activities, etc.).
• Also, without the application menu integration, when you launch the AppImage a default icon (Setting Gear in Ubuntu) is shown and not the app icon.

How to integrate an AppImage in your Menu

1. Download and place the appimage

   • You can create a dedicated folder in your home directory for placing all AppImages. E.g: mkdir -p ~/Applications

2. Make the image executable: chmod +x ~/Applications/YourApp.AppImage

3. Download an icon (optional)

   • For a seamless look, download an official icon for the app (a .png file).
   • Save it as ~/Applications/YourApp.png.

4. Create a desktop entry file

   • Desktop entry files (.desktop) tell your desktop environment how to launch an application and what icon to use.

   • Create a new file as ~/Applications/YourApp.desktop

   • The specification can be found on the freedesktop site

   • Minimally you need:

     • Type=Application - Specifies this is an application launcher.
     • Name=Your App Name - The name shown in the menu.
     • Exec=/path/to/your/executable - The command to run your app.
     • Icon=/path/to/icon.png - For a visible icon (optional, but recommended).
     • Categories=Utility; - For proper menu placement.
     • Terminal=false - If your app does not need a terminal.
     • StartupWMClass=yourappclass - See below for details.

   • Example desktop file for DB Browser for SQLite

      1[Desktop Entry]
      2Name=DB Browser for SQLite
      3Comment=DB Browser for SQLite is a light GUI editor for SQLite databases
      4Exec=/home/YOUR_USERNAME/Applications/DB.Browser.for.SQLite-v3.13.1-x86.64-v2.AppImage --no-sandbox
      5Icon=/home/YOUR_USERNAME/Applications/sqlitebrowser.png
      6Terminal=false
      7X-MultipleArgs=false
      8Type=Application
      9Categories=Development;Utility;Database;
     10StartupWMClass=sqlitebrowser
     

5. The StartupWMClass field

   • StartupWMClass is a key you can add to your .desktop file.
   • It helps your desktop environment associate a running application window with its launcher entry.
   • If you dont add this entry, you might see duplicate icons in your dock/taskbar when the app is running. Also, The running app might not be highlighted as launched.
   • If you are not aware of the class name you can detect the Correct StartupWMClass as:
     • Launch the AppImage (e.g., run it from terminal or double-click).
     • Open a terminal and run the following command: xprop | grep WM_CLASS
     • Click on the opened application window.
     • Read the terminal output, which will look like: WM_CLASS(STRING) = "sqlitebrowser", "DB Browser for SQLite"
     • You can add this to the desktop entry

6. Copy the desktop file to local apps folder: cp ~/Applications/YourApp.desktop ~/.local/share/applications/YourApp.desktop

7. Make it executable: chmod +x ~/.local/share/applications/YourApp.desktop

8. Refresh system databases

   • Refresh the application desktop: update-desktop-database ~/.local/share/applications/
   • Refresh the icons cache: sudo update-icon-caches /usr/share/icons/*

9. Launch from your application menu

   • Now, search for your application in your application menu (Launcher, Dash, Activities, etc.).
   • E.g By pressing the window key in Ubuntu.
   • You should see your new entry, complete with icon
   • Click to launch!