jQuery UI Autocomplete Combobox Very Slow With Large Select Lists

Question

I\'m using a modified version of the jQuery UI Autocomplete Combobox, as seen here: http://jqueryui.com/demos/autocomplete/#combobox

For the sake of this questio

Answer 1

I like the answer from Berro. But because it was still a bit slow (I had about 3000 options in select), i modified it slightly so that only first N matching results are displayed. I also added an item at the end notifying the user that more results are available and canceled focus and select events for that item.

Here is modified code for source and select functions and added one for focus:

source: function( request, response ) {
    var matcher = new RegExp( $.ui.autocomplete.escapeRegex(request.term), "i" );
    var select_el = select.get(0); // get dom element
    var rep = new Array(); // response array
    var maxRepSize = 10; // maximum response size  
    // simple loop for the options
    for (var i = 0; i < select_el.length; i++) {
        var text = select_el.options[i].text;
        if ( select_el.options[i].value && ( !request.term || matcher.test(text) ) )
            // add element to result array
            rep.push({
                label: text, // no more bold
                value: text,
                option: select_el.options[i]
            });
        if ( rep.length > maxRepSize ) {
            rep.push({
                label: "... more available",
                value: "maxRepSizeReached",
                option: ""
            });
            break;
        }
     }
     // send response
     response( rep );
},          
select: function( event, ui ) {
    if ( ui.item.value == "maxRepSizeReached") {
        return false;
    } else {
        ui.item.option.selected = true;
        self._trigger( "selected", event, {
            item: ui.item.option
        });
    }
},
focus: function( event, ui ) {
    if ( ui.item.value == "maxRepSizeReached") {
        return false;
    }
},