Open Autocomplete on Focus

Open Autocomplete on Focus

Hi,

I'm trying to make autocomplete work like a combobox (I saw the example but I don't want the button).
So I wrote juste the following code:
  1. $("input#autocomplete").focus(function () { $(this).autocomplete('search',''); })
But nothing happens ...
When I add a space at the end of each option, and I search for ' ' it works:
  1. $("input#autocomplete").focus(function () { $(this).autocomplete('search',' '); });
But it's not clean at all.
How can I open the autocomplete with all the options in it?

Thank for your help,

Thierry.