Creating an Application Launcher for GNOME 3 in Ubuntu

On Ubuntu 20 (Focal Fossa), create a launcher with alacarte. The generated .desktop file is automatically placed in ~/.local/share/applications.

Move it from there to /usr/share/applications/ if it is to be accessible to all the computer's users.

create a file called intellij.desktop in the directory /usr/share/applications/

my file looks like this

[Desktop Entry]
Name=IntelliJ IDEA Community Edition
Comment=Free Java, Groovy, Scala and Android applications development
Exec=/path/to/your/bin/idea.sh
Path=/path/to/your/bin
Terminal=false
Icon=intellij-idea-ce
Type=Application
Categories=Development;IDE

for more details check this website, http://standards.freedesktop.org/desktop-entry-spec/desktop-entry-spec-latest.html

edit: mlissner (Thank you!) mentioned that intelliJ in particular implemented a feature to add that Icon/Launcher automatically. Just open IntelliJ IDE, go to Tools and click Create Desktop Entry...

Run Intellij, then go to Tools > Create Desktop Entry.