[Summary view] [Print] [Text view]

   1  /**
   2  * hoverIntent is similar to jQuery's built-in "hover" function except that
   3  * instead of firing the onMouseOver event immediately, hoverIntent checks
   4  * to see if the user's mouse has slowed down (beneath the sensitivity
   5  * threshold) before firing the onMouseOver event.
   6  * 
   7  * hoverIntent r6 // 2011.02.26 // jQuery 1.5.1+
   8  * <http://cherne.net/brian/resources/jquery.hoverIntent.html>
   9  * 
  10  * hoverIntent is currently available for use in all personal or commercial 
  11  * projects under both MIT and GPL licenses. This means that you can choose 
  12  * the license that best suits your project, and use it accordingly.
  13  * 
  14  * // basic usage (just like .hover) receives onMouseOver and onMouseOut functions
  15  * $("ul li").hoverIntent( showNav , hideNav );
  16  * 
  17  * // advanced usage receives configuration object only
  18  * $("ul li").hoverIntent({
  19  *    sensitivity: 7, // number = sensitivity threshold (must be 1 or higher)
  20  *    interval: 100,   // number = milliseconds of polling interval
  21  *    over: showNav,  // function = onMouseOver callback (required)
  22  *    timeout: 0,   // number = milliseconds delay before onMouseOut function call
  23  *    out: hideNav    // function = onMouseOut callback (required)
  24  * });
  25  * 
  26  * @param  f  onMouseOver function || An object with configuration options
  27  * @param  g  onMouseOut function  || Nothing (use configuration options object)
  28  * @author    Brian Cherne brian(at)cherne(dot)net
  29  */
  30  (function($) {
  31      $.fn.hoverIntent = function(f,g) {
  32          // default configuration options
  33          var cfg = {
  34              sensitivity: 7,
  35              interval: 100,
  36              timeout: 0
  37          };
  38          // override configuration options with user supplied object
  39          cfg = $.extend(cfg, g ? { over: f, out: g } : f );
  40  
  41          // instantiate variables
  42          // cX, cY = current X and Y position of mouse, updated by mousemove event
  43          // pX, pY = previous X and Y position of mouse, set by mouseover and polling interval
  44          var cX, cY, pX, pY;
  45  
  46          // A private function for getting mouse position
  47          var track = function(ev) {
  48              cX = ev.pageX;
  49              cY = ev.pageY;
  50          };
  51  
  52          // A private function for comparing current and previous mouse position
  53          var compare = function(ev,ob) {
  54              ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t);
  55              // compare mouse positions to see if they've crossed the threshold
  56              if ( ( Math.abs(pX-cX) + Math.abs(pY-cY) ) < cfg.sensitivity ) {
  57                  $(ob).unbind("mousemove",track);
  58                  // set hoverIntent state to true (so mouseOut can be called)
  59                  ob.hoverIntent_s = 1;
  60                  return cfg.over.apply(ob,[ev]);
  61              } else {
  62                  // set previous coordinates for next time
  63                  pX = cX; pY = cY;
  64                  // use self-calling timeout, guarantees intervals are spaced out properly (avoids JavaScript timer bugs)
  65                  ob.hoverIntent_t = setTimeout( function(){compare(ev, ob);} , cfg.interval );
  66              }
  67          };
  68  
  69          // A private function for delaying the mouseOut function
  70          var delay = function(ev,ob) {
  71              ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t);
  72              ob.hoverIntent_s = 0;
  73              return cfg.out.apply(ob,[ev]);
  74          };
  75  
  76          // A private function for handling mouse 'hovering'
  77          var handleHover = function(e) {
  78              // copy objects to be passed into t (required for event object to be passed in IE)
  79              var ev = jQuery.extend({},e);
  80              var ob = this;
  81  
  82              // cancel hoverIntent timer if it exists
  83              if (ob.hoverIntent_t) { ob.hoverIntent_t = clearTimeout(ob.hoverIntent_t); }
  84  
  85              // if e.type == "mouseenter"
  86              if (e.type == "mouseenter") {
  87                  // set "previous" X and Y position based on initial entry point
  88                  pX = ev.pageX; pY = ev.pageY;
  89                  // update "current" X and Y position based on mousemove
  90                  $(ob).bind("mousemove",track);
  91                  // start polling interval (self-calling timeout) to compare mouse coordinates over time
  92                  if (ob.hoverIntent_s != 1) { ob.hoverIntent_t = setTimeout( function(){compare(ev,ob);} , cfg.interval );}
  93  
  94              // else e.type == "mouseleave"
  95              } else {
  96                  // unbind expensive mousemove event
  97                  $(ob).unbind("mousemove",track);
  98                  // if hoverIntent state is true, then call the mouseOut function after the specified delay
  99                  if (ob.hoverIntent_s == 1) { ob.hoverIntent_t = setTimeout( function(){delay(ev,ob);} , cfg.timeout );}
 100              }
 101          };
 102  
 103          // bind the function to the two event listeners
 104          return this.bind('mouseenter',handleHover).bind('mouseleave',handleHover);
 105      };
 106  })(jQuery);