The UI component of typeahead.js is available as a jQuery plugin. It's responsible for rendering suggestions and handling DOM interactions.

• Features
• Usage
  • API
  • Options
  • Datasets
  • Custom Events
  • Class Names

• Displays suggestions to end-users as they type
• Shows top suggestion as a hint (i.e. background text)
• Supports custom templates to allow for UI flexibility
• Works well with RTL languages and input method editors
• Highlights query matches within the suggestion
• Triggers custom events to encourage extensibility

• jQuery#typeahead(options, [*datasets])
• jQuery#typeahead('val')
• jQuery#typeahead('val', val)
• jQuery#typeahead('destroy')
• jQuery.fn.typeahead.noConflict()

For a given input[type="text"], enables typeahead functionality. options is an options hash that's used for configuration. Refer to Options for more info regarding the available configs. Subsequent arguments (*datasets), are individual option hashes for datasets. For more details regarding datasets, refer to Datasets.

$('.typeahead').typeahead({
  minLength: 3,
  highlight: true
},
{
  name: 'my-dataset',
  source: mySource
});

Returns the current value of the typeahead. The value is the text the user has entered into the input element.

var myVal = $('.typeahead').typeahead('val');

Sets the value of the typeahead. This should be used in place of jQuery#val.

$('.typeahead').typeahead('val', myVal);

Opens the suggestion menu.

$('.typeahead').typeahead('open');

Closes the suggestion menu.

$('.typeahead').typeahead('close');

Removes typeahead functionality and reverts the input element back to its original state.

$('.typeahead').typeahead('destroy');

Returns a reference to the typeahead plugin and reverts jQuery.fn.typeahead to its previous value. Can be used to avoid naming collisions.

var typeahead = jQuery.fn.typeahead.noConflict();
jQuery.fn._typeahead = typeahead;

When initializing a typeahead, there are a number of options you can configure.

• highlight – If true, when suggestions are rendered, pattern matches for the current query in text nodes will be wrapped in a strong element with its class set to {{classNames.highlight}}. Defaults to false.

• hint – If false, the typeahead will not show a hint. Defaults to true.

• autoselect – If true, the first suggestion will be selected when pressing the Enter key.

• minLength – The minimum character length needed before suggestions start getting rendered. Defaults to 1.

• classNames – For overriding the default class names used. See Class Names for more details.

A typeahead is composed of one or more datasets. When an end-user modifies the value of a typeahead, each dataset will attempt to render suggestions for the new value.

For most use cases, one dataset should suffice. It's only in the scenario where you want rendered suggestions to be grouped based on some sort of categorical relationship that you'd need to use multiple datasets. For example, on twitter.com, the search typeahead groups results into recent searches, trends, and accounts – that would be a great use case for using multiple datasets.

Datasets can be configured using the following options.

• source – The backing data source for suggestions. Expected to be a function with the signature (query, syncResults, asyncResults). syncResults should be called with suggestions computed synchronously and asyncResults should be called with suggestions computed asynchronously (e.g. suggestions that come for an AJAX request). source can also be a Bloodhound instance. Required.

• async – Lets the dataset know if async suggestions should be expected. If not set, this information is inferred from the signature of source i.e. if the source function expects 3 arguments, async will be set to true.

• name – The name of the dataset. This will be appended to {{classNames.dataset}}- to form the class name of the containing DOM element. Must only consist of underscores, dashes, letters (a-z), and numbers. Defaults to a random number.

• limit – The max number of suggestions to be displayed. Defaults to 5.

• display | displayKey – For a given suggestion, determines the string representation of it. This will be used when setting the value of the input control after a suggestion is selected. Can be either a key string or a function that transforms a suggestion object into a string. Defaults to stringifying the suggestion.

• templates – A hash of templates to be used when rendering the dataset. Note a precompiled template is a function that takes a JavaScript object as its first argument and returns a HTML string.

  • notFound – Rendered when 0 suggestions are available for the given query. Can be either a HTML string or a precompiled template. If it's a precompiled template, the passed in context will contain query.

  • pending - Rendered when 0 synchronous suggestions are available but asynchronous suggestions are expected. Can be either a HTML string or a precompiled template. If it's a precompiled template, the passed in context will contain query.

  • header– Rendered at the top of the dataset when suggestions are present. Can be either a HTML string or a precompiled template. If it's a precompiled template, the passed in context will contain query and suggestions.

  • footer– Rendered at the bottom of the dataset when suggestions are present. Can be either a HTML string or a precompiled template. If it's a precompiled template, the passed in context will contain query and suggestions.

  • suggestion – Used to render a single suggestion. If set, this has to be a precompiled template. The associated suggestion object will serve as the context. Defaults to the value of display wrapped in a div tag i.e. <div>{{value}}</div>.

The following events get triggered on the input element during the life-cycle of a typeahead.

• typeahead:active – Fired when the typeahead moves to active state.

• typeahead:idle – Fired when the typeahead moves to idle state.

• typeahead:open – Fired when the results container is opened.

• typeahead:close – Fired when the results container is closed.

• typeahead:change – Normalized version of the native change event. Fired when input loses focus and the value has changed since it originally received focus.

• typeahead:render – Fired when suggestions are rendered for a dataset. The event handler will be invoked with 4 arguments: the jQuery event object, the suggestions that were rendered, a flag indicating whether the suggestions were fetched asynchronously, and the name of the dataset the rendering occurred in.

• typeahead:select – Fired when a suggestion is selected. The event handler will be invoked with 3 arguments: the jQuery event object, the suggestion object that was selected, and the name of the dataset the suggestion belongs to.

• typeahead:autocomplete – Fired when a autocompletion occurs. The event handler will be invoked with 3 arguments: the jQuery event object, the suggestion object that was used for autocompletion, and the name of the dataset the suggestion belongs to.

• typeahead:cursorchange – Fired when the results container cursor moves. The event handler will be invoked with 3 arguments: the jQuery event object, the suggestion object that was moved to, and the name of the dataset the suggestion belongs to.

• typeahead:asyncrequest – Fired when an async request for suggestions is sent. The event handler will be invoked with 3 arguments: the jQuery event object, the current query, and the name of the dataset the async request belongs to.

• typeahead:asynccancel – Fired when an async request is cancelled. The event handler will be invoked with 3 arguments: the jQuery event object, the current query, and the name of the dataset the async request belonged to.

• typeahead:asyncreceive – Fired when an async request completes. The event handler will be invoked with 3 arguments: the jQuery event object, the current query, and the name of the dataset the async request belongs to.

Example usage:

$('.typeahead').bind('typeahead:select', function(ev, suggestion) {
  console.log('Selection: ', suggestion);
});

NOTE: Every event does not supply the same arguments. See the event descriptions above for details on each event's argument list.

• input - Added to input that's initialized into a typeahead. Defaults to tt-input.

• hint - Added to hint input. Defaults to tt-hint.

• menu - Added to menu element. Defaults to tt-menu.

• dataset - Added to dataset elements. to Defaults to tt-dataset.

• suggestion - Added to suggestion elements. Defaults to tt-suggestion.

• empty - Added to menu element when it contains no content. Defaults to tt-empty.

• open - Added to menu element when it is opened. Defaults to tt-open.

• cursor - Added to suggestion element when menu cursor moves to said suggestion. Defaults to tt-cursor.

• highlight - Added to the element that wraps highlighted text. Defaults to tt-highlight.

To override any of these defaults, you can use the classNames option:

$('.typeahead').typeahead({
  classNames: {
    input: 'Typeahead-input',
    hint: 'Typeahead-hint',
    selectable: 'Typeahead-selectable'
  }
});