dom.js

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/*
Copyright (c) 2006, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.net/yui/license.txt
Version: 0.11.3
*/

/**
 * @class Provides helper methods for DOM elements.
 */
YAHOO.util.Dom = function() {
   var ua = navigator.userAgent.toLowerCase();
   var isOpera = (ua.indexOf('opera') > -1);
   var isSafari = (ua.indexOf('safari') > -1);
   var isIE = (window.ActiveXObject);

   var id_counter = 0;
   var util = YAHOO.util; // internal shorthand
   var property_cache = {}; // to cache case conversion for set/getStyle

   var toCamel = function(property) {
      var convert = function(prop) {
         var test = /(-[a-z])/i.exec(prop);
         return prop.replace(RegExp.$1, RegExp.$1.substr(1).toUpperCase());
      };

      while(property.indexOf('-') > -1) {
         property = convert(property);
      }

      return property;
      //return property.replace(/-([a-z])/gi, function(m0, m1) {return m1.toUpperCase()}) // cant use function as 2nd arg yet due to safari bug
   };

   var toHyphen = function(property) {
      if (property.indexOf('-') > -1) { // assume hyphen
         return property;
      }

      var converted = '';
      for (var i = 0, len = property.length;i < len; ++i) {
         if (property.charAt(i) == property.charAt(i).toUpperCase()) {
            converted = converted + '-' + property.charAt(i).toLowerCase();
         } else {
            converted = converted + property.charAt(i);
         }
      }

      return converted;
      //return property.replace(/([a-z])([A-Z]+)/g, function(m0, m1, m2) {return (m1 + '-' + m2.toLowerCase())});
   };

   // improve performance by only looking up once
   var cacheConvertedProperties = function(property) {
      property_cache[property] = {
         camel: toCamel(property),
         hyphen: toHyphen(property)
      };
   };

   return {
      /**
       * Returns an HTMLElement reference
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID for getting a DOM reference, an actual DOM reference, or an Array of IDs and/or HTMLElements.
       * @return {HTMLElement/Array} A DOM reference to an HTML element or an array of HTMLElements.
       */
      get: function(el) {
         if (!el) { return null; } // nothing to work with

         if (typeof el != 'string' && !(el instanceof Array) ) { // assuming HTMLElement or HTMLCollection, so pass back as is
            return el;
         }

         if (typeof el == 'string') { // ID
            return document.getElementById(el);
         }
         else { // array of ID's and/or elements
            var collection = [];
            for (var i = 0, len = el.length; i < len; ++i) {
               collection[collection.length] = util.Dom.get(el[i]);
            }

            return collection;
         }

         return null; // safety, should never happen
      },

      /**
       * Normalizes currentStyle and ComputedStyle.
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
       * @param {String} property The style property whose value is returned.
       * @return {String/Array} The current value of the style property for the element(s).
       */
      getStyle: function(el, property) {
         var f = function(el) {
            var value = null;
            var dv = document.defaultView;

            if (!property_cache[property]) {
               cacheConvertedProperties(property);
            }

            var camel = property_cache[property]['camel'];
            var hyphen = property_cache[property]['hyphen'];

            if (property == 'opacity' && el.filters) {// IE opacity
               value = 1;
               try {
                  value = el.filters.item('DXImageTransform.Microsoft.Alpha').opacity / 100;
               } catch(e) {
                  try {
                     value = el.filters.item('alpha').opacity / 100;
                  } catch(e) {}
               }
            } else if (el.style[camel]) { // camelCase for valid styles
               value = el.style[camel];
            }
            else if (isIE && el.currentStyle && el.currentStyle[camel]) { // camelCase for currentStyle; isIE to workaround broken Opera 9 currentStyle
               value = el.currentStyle[camel];
            }
            else if ( dv && dv.getComputedStyle ) { // hyphen-case for computedStyle
               var computed = dv.getComputedStyle(el, '');

               if (computed && computed.getPropertyValue(hyphen)) {
                  value = computed.getPropertyValue(hyphen);
               }
            }

            return value;
         };

         return util.Dom.batch(el, f, util.Dom, true);
      },

      /**
       * Wrapper for setting style properties of HTMLElements.  Normalizes "opacity" across modern browsers.
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
       * @param {String} property The style property to be set.
       * @param {String} val The value to apply to the given property.
       */
      setStyle: function(el, property, val) {
         if (!property_cache[property]) {
            cacheConvertedProperties(property);
         }

         var camel = property_cache[property]['camel'];

         var f = function(el) {
            switch(property) {
               case 'opacity' :
                  if (isIE && typeof el.style.filter == 'string') { // in case not appended
                     el.style.filter = 'alpha(opacity=' + val * 100 + ')';

                     if (!el.currentStyle || !el.currentStyle.hasLayout) {
                        el.style.zoom = 1; // when no layout or cant tell
                     }
                  } else {
                     el.style.opacity = val;
                     el.style['-moz-opacity'] = val;
                     el.style['-khtml-opacity'] = val;
                  }

                  break;
               default :
                  el.style[camel] = val;
            }


         };

         util.Dom.batch(el, f, util.Dom, true);
      },

      /**
       * Gets the current position of an element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
       @ return {Array} The XY position of the element(s)
       */
      getXY: function(el) {
         var f = function(el) {

         // has to be part of document to have pageXY
            if (el.offsetParent === null || this.getStyle(el, 'display') == 'none') {
               return false;
            }

            var parentNode = null;
            var pos = [];
            var box;

            if (el.getBoundingClientRect) { // IE
               box = el.getBoundingClientRect();
               var doc = document;
               if ( !this.inDocument(el) && parent.document != document) {// might be in a frame, need to get its scroll
                  doc = parent.document;

                  if ( !this.isAncestor(doc.documentElement, el) ) {
                     return false;
                  }

               }

               var scrollTop = Math.max(doc.documentElement.scrollTop, doc.body.scrollTop);
               var scrollLeft = Math.max(doc.documentElement.scrollLeft, doc.body.scrollLeft);

               return [box.left + scrollLeft, box.top + scrollTop];
            }
            else { // safari, opera, & gecko
               pos = [el.offsetLeft, el.offsetTop];
               parentNode = el.offsetParent;
               if (parentNode != el) {
                  while (parentNode) {
                     pos[0] += parentNode.offsetLeft;
                     pos[1] += parentNode.offsetTop;
                     parentNode = parentNode.offsetParent;
                  }
               }
               if (isSafari && this.getStyle(el, 'position') == 'absolute' ) { // safari doubles in some cases
                  pos[0] -= document.body.offsetLeft;
                  pos[1] -= document.body.offsetTop;
               }
            }

            if (el.parentNode) { parentNode = el.parentNode; }
            else { parentNode = null; }

            while (parentNode && parentNode.tagName.toUpperCase() != 'BODY' && parentNode.tagName.toUpperCase() != 'HTML')
            { // account for any scrolled ancestors
               if (util.Dom.getStyle(parentNode, 'display') != 'inline') { // work around opera inline scrollLeft/Top bug
                  pos[0] -= parentNode.scrollLeft;
                  pos[1] -= parentNode.scrollTop;
               }

               if (parentNode.parentNode) { parentNode = parentNode.parentNode; }
               else { parentNode = null; }
            }


            return pos;
         };

         return util.Dom.batch(el, f, util.Dom, true);
      },

      /**
       * Gets the current X position of an element based on page coordinates.  The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
       * @return {String/Array} The X position of the element(s)
       */
      getX: function(el) {
         var f = function(el) {
            return util.Dom.getXY(el)[0];
         };

         return util.Dom.batch(el, f, util.Dom, true);
      },

      /**
       * Gets the current Y position of an element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
       * @return {String/Array} The Y position of the element(s)
       */
      getY: function(el) {
         var f = function(el) {
            return util.Dom.getXY(el)[1];
         };

         return util.Dom.batch(el, f, util.Dom, true);
      },

      /**
       * Set the position of an html element in page coordinates, regardless of how the element is positioned.
       * The element(s) must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
       * @param {String/HTMLElement/Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
       * @param {Array} pos Contains X & Y values for new position (coordinates are page-based)
       * @param {Boolean} noRetry By default we try and set the position a second time if the first fails
       */
      setXY: function(el, pos, noRetry) {
         var f = function(el) {
            var style_pos = this.getStyle(el, 'position');
            if (style_pos == 'static') { // default to relative
               this.setStyle(el, 'position', 'relative');
               style_pos = 'relative';
            }

            var pageXY = this.getXY(el);
            if (pageXY === false) { // has to be part of doc to have pageXY
               return false;
            }

            var delta = [ // assuming pixels; if not we will have to retry
               parseInt( this.getStyle(el, 'left'), 10 ),
               parseInt( this.getStyle(el, 'top'), 10 )
            ];

            if ( isNaN(delta[0]) ) {// in case of 'auto'
               delta[0] = (style_pos == 'relative') ? 0 : el.offsetLeft;
            }
            if ( isNaN(delta[1]) ) { // in case of 'auto'