How to setup predictive text (autocomplete) on Mac?

Question

Apart from native support for text shortcuts, how can I enable autocomplete on Mac, presumably Cocoa applications? I mean autocomplete from dictionary or words previously used. Something like Samsung's input system has.

Answer 1

The closest things I've found to what you are looking for are this text editor experiment that you have to compile yourself

http://alvinalexander.com/java/type-ahead-continuous-predictive-text-editor-auto-complete

And this Chrome extension for Gmail https://complete.li

Both would require you to type in their respective places and then paste into your application of choice, but I haven't found anything that works systemwide.