Recently I was interested in programmatically changing the icon of a specific directory in KDE’s default file manager Dolphin. Why would I need that? Well this can be handy if you want to dynamically adapt the colors of a directory icon in certain situations: Maybe a file quota is exceeded, maybe you want to react to system events and reflect this by setting a specific icon for relevant directories.
Thankfully, KDE already offers such a helper tool by default:
enables you to modify KDE configuration files easily by passing the file name,
the group and a key-value pair. So to change an icon, simply update Dolphin’s
.directory files like this:
kwriteconfig5 \ --file ~/Documents/.directory \ --group 'Desktop Entry' \ --key 'Icon' 'folder-red'