Change Mac App Icon With A Terminal Command

Question

I like to use custom icons for a few apps. However, of course, when an app updates the icon is reset. I'd like to be able to run a script to instantly update all of my custom app icons automatically.

At present, I right click on an app and select get info. Then, I can drag an .icns file on to the original icon at the top of this window. Relaunch the dock, and done! Much like this tutorial.

Does anyone know if there's a terminal command to achieve the same thing? I've seen variations that dive into an app's resources folder and change the .icns file there, but this is a different process, and I haven't had much look with this.

Any ideas?

Answer 1

I have a folder called “App Icons” in my Dropbox. Just inside I have a shell script called install.sh, and next to that I have folders for each app I want custom icons for. Currently that’s Atom and Mattermost.

Inside each directory I have atom.icns and Mattermost.icns, respectively.

To get both apps updated I run this script:

#!/usr/bin/env bash

set -euf -o pipefail
umask 077
has_copied=0

for atom in Atom "Atom Beta"; do
    path="/Applications/${atom}.app"
    [ -d "${path}" ] && \
    cp ./Atom/atom.icns "${path}/Contents/Resources/atom.icns" && \
    touch "${path}" && \
    has_copied=1
done

for mattermost in Mattermost; do
    path="/Applications/${mattermost}.app"
    [ -d "${path}" ] && \
    cp ./Mattermost/Mattermost.icns "${path}/Contents/Resources/Mattermost.icns" && \
    touch "${path}" && \
    has_copied=2
done

[ ${has_copied} = "2" ] && killall Dock

Atom usually updates immediately with the [ ${has_copied} = "2" ] && killall Dock line. Mattermost does not, but I’m guessing that’s a case-by-case basis. I suspect there is a much smarter way to loop through all available icons and update their respective apps, but I’m no bash maestro, so I kept it simple.

In order to run this automatically you might use Automator, or event better, follow the instructions in this SO answer: https://stackoverflow.com/a/13372744/347884

If you choose the second route, make sure your shell script is executable:

chmod a+x /path/to/script.sh

Have fun!