jQuery.effects.define( name [, mode ], effect )Returns: Functionversion added: 1.12
Description: Defines an effect.
Defines a new effect for use with .effect(), .show(), .hide(), and .toggle(). The effect method is invoked with this being a single DOM element. The done argument must be invoked when the animation is complete.
jQuery.effects.define() stores the new effect in jQuery.effects.effect[ name ] and returns the function that was provided as the effect parameter.
Example:
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery.effects.define demo</title>
<link rel="stylesheet" href="https://code.jquery.com/ui/1.13.3/themes/smoothness/jquery-ui.css">
<style>
.elem {
position: absolute;
width: 150px;
height: 150px;
background: #3b679e;
}
</style>
<script src="https://code.jquery.com/jquery-3.7.1.js"></script>
<script src="https://code.jquery.com/ui/1.13.3/jquery-ui.js"></script>
</head>
<body>
Click anywhere!
<div class="elem"></div>
<script>
$.effects.define( "fade", "toggle", function( options, done ) {
var show = options.mode === "show";
$( this )
.css( "opacity", show ? 0 : 1 )
.animate( {
opacity: show ? 1 : 0
}, {
queue: false,
duration: options.duration,
easing: options.easing,
complete: done
} );
} );
$( document ).on( "click", function() {
$( ".elem" ).toggle( "fade" );
} );
</script>
</body>
</html> 
