Server-side update of AutocompleteInput completion list

JQuery allows to use ajax to POST and request from the server the list of items to display on autocomplete (example from JWueryUI)

I would like to do the same with AutocompleteInput

I presume that using the JS callback definition will not work as it will get activated on “return pressed” rather than on “text typed”, as it inherits from, textinput

What is the correct approach at giving Autocomplete Widget a dynamic, server side update of the completion list? Thanks

Further to this, Autocomplete seems broken: when I try to scroll through the list of suggestions, they disappear