Chosen - Prototype Version (v2.2.0)

Chosen automatically highlights selected options and removes disabled and / or hidden options.

The disable_search_threshold option can be specified to hide the search input on single selects if there are n or fewer options.

 new Chosen($("chosen_select_field"),{disable_search_threshold: 10}); 

Chosen automatically sets the default field text ("Choose a country...") by reading the select element's data-placeholder value. If no data-placeholder value is present, it will default to "Select an Option" or "Select Some Options" depending on whether the select is single or multiple. You can change these elements in the plugin js file as you see fit.

<select data-placeholder="Choose a country..." multiple class="chosen-select">

Note: on single selects, the first element is assumed to be selected by the browser. To take advantage of the default text support, you will need to include a blank option as the first element of your select list - or include an element with the same label as the placeholder and set the hidden, selected and disabled attributes on it for a more graceful degradation on devices Chosen does not support:

<option value="" selected disabled hidden>Choose a country...</option>

Setting the "No results" search text is as easy as passing an option when you create Chosen:

new Chosen($("chosen_select_field"),{no_results_text: "Oops, nothing found!"}); 

You can easily limit how many options the user can select:

new Chosen($("chosen_select_field"),{max_selected_options: 5}); 

If you try to select another option with limit reached chosen:maxselected event is triggered:

$("chosen_select_field").observe("chosen:maxselected", function(evt) { ... }); 

When a single select box isn't a required field, you can set allow_single_deselect: true and Chosen will add a UI element for option deselection. This will only work if the first option has blank text.

You can set right-to-left text by setting rtl: true

 $(".chosen-select").chosen({rtl: true}); 

• Observing Form Field Changes

  When working with form fields, you often want to perform some behavior after a value has been selected or deselected. Whenever a user selects a field in Chosen, it triggers a "change" event on the original form field. That lets you do something like this:

  $("#form_field").chosen().change( … );

  Note: Prototype doesn't offer support for triggering standard browser events. Event.simulate is required to trigger the change event when using the Prototype version.

• Updating Chosen Dynamically

  If you need to update the options in your select field and want Chosen to pick up the changes, you'll need to trigger the "chosen:updated" event on the field. Chosen will re-build itself based on the updated content.

  Event.fire($("form_field"), "chosen:updated");

• Destroying Chosen

  To destroy Chosen and revert back to the native select, call destroy on the Chosen instance:

  chosen = new Chosen($("form_field"));
  
  // ...later
  chosen.destroy();

Using a custom width with Chosen is as easy as passing an option when you create Chosen:

new Chosen($("chosen_select_field"),{width: "95%"}); 

Use labels just like you would a standard select