In unity, we can drag files on application's button in the launcher to open that file with that application - however, looks like its hard to change default application.
I use Komodo as editor, and my goal is to open php files dragging on the Komodo button on the launcher.
The problem is that with gtk3 is a bit tricky to add custom application to open mimetypes..
I've created the button from the Main Menu, then i user mimeopen -d file.php
to set komodo as default; Now, if i double-click on a php file, it get open with komodo - but I cant drag php files on komodo button on launcher.