Create an empty file with the following code:
Example 1. A Simple Extension
from gi.repository import Caja, GObject class ColumnExtension(GObject.GObject, Caja.MenuProvider): def __init__(self): pass def menu_activate_cb(self, menu, file): print "menu_activate_cb",file def get_file_items(self, window, files): if len(files) != 1: return file = files[0] item = Caja.MenuItem( name="SimpleMenuExtension::Show_File_Name", label="Showing %s" % file.get_name(), tip="Showing %s" % file.get_name() ) item.connect('activate', self.menu_activate_cb, file) return [item]
Save this file as TestExtension.py in the ~/.local/share/caja-python/extensions folder. You may need to create this folder. To run, simply restart Caja.
Once Caja restarts, right-click on a file and you should see a new menu item, "Showing #filename#". It is as simple as that!
As mentioned above, in order to get loaded by Caja, a python extension must import the Caja module from gi.repository, create a class derived from a caja *Provider and a gobject.GObject, and create the methods that will be called by Caja when it requests information from its providers. In this case, when someone right-clicks on a file, Caja will ask all of its MenuProviders for additional menu items to show the user. When folders or files are clicked, the get_file_items method is called and a list of Caja.MenuItems is expected.