jQuery UI Autocomplete open Event

jQuery UI consists of GUI widgets, visual effects, and themes implemented using HTML, CSS, and jQuery. jQuery UI is great for building UI interfaces for the webpages. The jQuery UI Autocomplete widget is used to perform autocomplete enables to quickly find and select from a pre-populated list of values as they type, leveraging searching and filtering.

The jQuery UI Autocomplete open event is used to trigger when the suggestion menu is opened or updated.

Syntax:

Initialize the autocomplete with the open callback specified:

$( ".selector" ).autocomplete({
 open: function( event, ui ) {}
});

Bind an event listener to the autocompleteopen event: 

$( ".selector" ).on(
 "autocompleteopen",
 function( event, ui ) {}
);

Parameters: It accepts a callback function that holds two parameters. 

• event: It accepts Event type value.
• ui: It accepts Object type value. The ui object can be empty but used for consistency with other events.

CDN Link: First, add jQuery UI scripts needed for your project. 

<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/smoothness/jquery-ui.css">
<script src="//code.jquery.com/jquery-1.12.4.js"></script>
<script src="//code.jquery.com/ui/1.12.1/jquery-ui.js"></script>

Example: This example describes the uses of jQuery UI Autocomplete open event. 

Output: 

Reference: https://api.jqueryui.com/autocomplete/#event-open