Question

Imagine a json file with the following data:

[
    {
        color: "red",
        value: "#f00"
    },
    {
        color: "green",
        value: "#0f0"
    },
    {
        color: "blue",
        value: "#00f"
    },
    {
        color: "cyan",
        value: "#0ff"
    }
]

Using jQuery’s autocomplete method, I want it to be able to display the color as options to select and insert value on a input.

<input type="text" name="selector" id="selector" />

<input type="text" name="color" id="color" />
<input type="text" name="value" id="value" />

The above doesn’t need introductions. Selector for the search on the colors, input.color with color value and input.value with value value.

EDIT:
I have this JSON data:

[{
    "label": "Sec\u00e7\u00e3o 1",
    "value": "1"
}, {
    "label": "Sec\u00e7\u00e3o 2",
    "value": "2"
}, {
    "label": "Sec\u00e7\u00e3o 3",
    "value": "3"
}, {
    "label": "Sec\u00e7\u00e3o 4",
    "value": "4"
}]

and this HTML:

<input type="text" id="name" />
<input type="text" id="value" />

and this jQuery:

$(document).ready(function(){
    $("#name").autocomplete({
        source: "json.php",
        select: function (event, ui) {
            $("#name").val(ui.label);
            $("#value").val(ui.value);
        }
    });
});

I followed Andrew’s answer and it prompts me to select the data, but if I alert ui.labeland ui.value variables, it says ‘undefined’. What am I missing?

Edit2:
Let’s say I have this HTML:

<input type="text" class="name" />
<input type="text" class="value" />

<input type="text" class="name" />
<input type="text" class="value" />

Is it possible to handle multiple selectors with the same .autocomplete() method? Like, select the label I want using the input.name and only update the input.value next to it?

[input.name] [input.value]
^ I select       ^ updates the
  a label           value next to it
[input.name] [input.value]
^ this stays intact ^

Answer 1

Using a remote data source:

$("#selector").autocomplete({
    source: function (request, response) {
         $.ajax({
             url: "my_server_side_resource.php",
             type: "GET",
             data: request,
             success: function (data) {
                 response($.map(data, function (el) {
                     return {
                         label: el.color,
                         value: el.value
                     };
                 }));
             }
         });
    },
    select: function (event, ui) {
        // Prevent value from being put in the input:
        this.value = ui.item.label;
        // Set the next input's value to the "value" of the item.
        $(this).next("input").val(ui.item.value);
        event.preventDefault();
    }
});

Tweak the $.ajax call as needed. This example will generate requests to your PHP resource that look like this:

my_server_side_resource.php?term=xyz

If you have control over your server-side code, you could change the data that’s returned to look like this:

[
    {
        label: "red",
        value: "#f00"
    }, /* etc */
]

You can simply use a string, the name of your server-side resource as the source:

$("#selector").autocomplete({
     source: "my_server_side_resource.php",
     select: /* same as above */
});

Check out the remote with JSONP example for a full example using a server-side resource.

Edit: See this example for a working demo using local data: http://jsfiddle.net/SMxY6/