Based on the instructions from Autocomplete in Eclipse for CodeIgniter 2, I tried to get it done with Aptana 3. It’s a little bit different, so here is what I did:
I modified the files from CodeIgniter like explained by TaggedZi.
Then I added a new user library. Open Aptana 3 and navigate to:
Window > Preferences > Aptana > Editors > PHP – Libraries
Click New user library, type in a name and select the path to the modified CodeIgniter library.
Deselect the library and close the Preferences.
Now open the properties of your actual project and go to PHP Buildpath > Libraries.
Uncheck “Use Project specified settings”and select the CodeIgniter library.
Done! Now Aptana 3 autocompletes the CodeIgniter 2 functions.
Edit: December 27, 2011
Some other neat solutions: Aptana 3 and CodeIgniter 2 code completion