Javascript onHover event

tmtest picture tmtest · Nov 4, 2008 · Viewed 149k times · Source

Is there a canonical way to set up a JS onHover event with the existing onmouseover, onmouseout and some kind of timers? Or just any method to fire an arbitrary function if and only if user has hovered over element for certain amount of time.

Answer

Peter Bailey picture Peter Bailey · Nov 4, 2008

How about something like this?

<html>
<head>
<script type="text/javascript">

var HoverListener = {
  addElem: function( elem, callback, delay )
  {
    if ( delay === undefined )
    {
      delay = 1000;
    }

    var hoverTimer;

    addEvent( elem, 'mouseover', function()
    {
      hoverTimer = setTimeout( callback, delay );
    } );

    addEvent( elem, 'mouseout', function()
    {
      clearTimeout( hoverTimer );
    } );
  }
}

function tester()
{
  alert( 'hi' );
}

//  Generic event abstractor
function addEvent( obj, evt, fn )
{
  if ( 'undefined' != typeof obj.addEventListener )
  {
    obj.addEventListener( evt, fn, false );
  }
  else if ( 'undefined' != typeof obj.attachEvent )
  {
    obj.attachEvent( "on" + evt, fn );
  }
}

addEvent( window, 'load', function()
{
  HoverListener.addElem(
      document.getElementById( 'test' )
    , tester 
  );
  HoverListener.addElem(
      document.getElementById( 'test2' )
    , function()
      {
        alert( 'Hello World!' );
      }
    , 2300
  );
} );

</script>
</head>
<body>
<div id="test">Will alert "hi" on hover after one second</div>
<div id="test2">Will alert "Hello World!" on hover 2.3 seconds</div>
</body>
</html>