position.js

简单博客功能实现

//建立X2.Position命名空间
X2.Position={
		//设定节点的绝对位置
	setPosition:function(e,x,y){
		Position.absolutize(e);
		e.style.left=x+'px';
		e.style.top=y+'px';
	}
		//将元素e放置在re的一侧，adj以[x,y]的形式表示修正值，默认为[0,0]
	,setLeft:function(e,re,adj){
		var _adj=adj||[0,0];
		var dim2=Element.getDimensions(e);
		var offdim=Position.cumulativeOffset(re);
		this.setPosition(e,offdim[0]-dim2.width-_adj[0],offdim[1]+_adj[1]);
	}
	,setRight:function(e,re,adj){
		var _adj=adj||[0,0];
		var dim=Element.getDimensions(re);
		var offdim=Position.cumulativeOffset(re);
		this.setPosition(e,offdim[0]+dim.width+_adj[0],offdim[1]+_adj[1]);
	}
	,setTop:function(e,re,adj){
		var _adj=adj||[0,0];
		var dim2=Element.getDimensions(e);
		var offdim=Position.cumulativeOffset(re);
		this.setPosition(e,offdim[0]+_adj[0],offdim[1]-dim2.height-_adj[1]);
	}
	,setBottom:function(e,re,adj){
		var _adj=adj||[0,0];
		var dim=Element.getDimensions(re);
		var offdim=Position.cumulativeOffset(re);
		this.setPosition(e,offdim[0]+_adj[0],offdim[1]+dim.height+_adj[1]);
	}

		//鼠标移出时判断从元素的哪个方向移出
	,leftOut:function(event,e){
		var x=Event.pointerX(event);
		return x<=Position.cumulativeOffset(e)[0]+1;
	}
	,rightOut:function(event,e){
		var x=Event.pointerX(event);
		return x>=Position.cumulativeOffset(e)[0]+Element.getDimensions(e).width;
	}
	,topOut:function(event,e){
		var y=Event.pointerY(event);
		//alert(y);
		//alert(Position.cumulativeOffset(e)[1]);
		return y<=Position.cumulativeOffset(e)[1]+1;
	}
	,bottomOut:function(event,e){
		var y=Event.pointerY(event);
		return y>=Position.cumulativeOffset(e)[1]+Element.getDimensions(e).height;
	}
	
	
}

var RicoUtil = {

   getElementsComputedStyle: function ( htmlElement, cssProperty, mozillaEquivalentCSS) {
      if ( arguments.length == 2 )
         mozillaEquivalentCSS = cssProperty;

      var el = $(htmlElement);
      if ( el.currentStyle )
         return el.currentStyle[cssProperty];
      else
         return document.defaultView.getComputedStyle(el, null).getPropertyValue(mozillaEquivalentCSS);
   },

   createXmlDocument : function() {
      if (document.implementation && document.implementation.createDocument) {
         var doc = document.implementation.createDocument("", "", null);

         if (doc.readyState == null) {
            doc.readyState = 1;
            doc.addEventListener("load", function () {
               doc.readyState = 4;
               if (typeof doc.onreadystatechange == "function")
                  doc.onreadystatechange();
            }, false);
         }

         return doc;
      }

      if (window.ActiveXObject)
          return Try.these(
            function() { return new ActiveXObject('MSXML2.DomDocument')   },
            function() { return new ActiveXObject('Microsoft.DomDocument')},
            function() { return new ActiveXObject('MSXML.DomDocument')    },
            function() { return new ActiveXObject('MSXML3.DomDocument')   }
          ) || false;

      return null;
   },

   getContentAsString: function( parentNode ) {
      return parentNode.xml != undefined ? 
         this._getContentAsStringIE(parentNode) :
         this._getContentAsStringMozilla(parentNode);
   },

   _getContentAsStringIE: function(parentNode) {
      var contentStr = "";
      for ( var i = 0 ; i < parentNode.childNodes.length ; i++ )
         contentStr += parentNode.childNodes[i].xml;
      return contentStr;
   },

   _getContentAsStringMozilla: function(parentNode) {
      var xmlSerializer = new XMLSerializer();
      var contentStr = "";
      for ( var i = 0 ; i < parentNode.childNodes.length ; i++ )
         contentStr += xmlSerializer.serializeToString(parentNode.childNodes[i]);
      return contentStr;
   },

   toViewportPosition: function(element) {
      return this._toAbsolute(element,true);
   },

   toDocumentPosition: function(element) {
      return this._toAbsolute(element,false);
   },

   /**
    *  Compute the elements position in terms of the window viewport
    *  so that it can be compared to the position of the mouse (dnd)
    *  This is additions of all the offsetTop,offsetLeft values up the
    *  offsetParent hierarchy, ...taking into account any scrollTop,
    *  scrollLeft values along the way...
    *
    * IE has a bug reporting a correct offsetLeft of elements within a
    * a relatively positioned parent!!!
    **/
   _toAbsolute: function(element,accountForDocScroll) {

      if ( navigator.userAgent.toLowerCase().indexOf("msie") == -1 )
         return this._toAbsoluteMozilla(element,accountForDocScroll);

      var x = 0;
      var y = 0;
      var parent = element;
      while ( parent ) {

         var borderXOffset = 0;
         var borderYOffset = 0;
         if ( parent != element ) {
            var borderXOffset = parseInt(this.getElementsComputedStyle(parent, "borderLeftWidth" ));
            var borderYOffset = parseInt(this.getElementsComputedStyle(parent, "borderTopWidth" ));
            borderXOffset = isNaN(borderXOffset) ? 0 : borderXOffset;
            borderYOffset = isNaN(borderYOffset) ? 0 : borderYOffset;
         }

         x += parent.offsetLeft - parent.scrollLeft + borderXOffset;
         y += parent.offsetTop - parent.scrollTop + borderYOffset;
         parent = parent.offsetParent;
      }

      if ( accountForDocScroll ) {
         x -= this.docScrollLeft();
         y -= this.docScrollTop();
      }

      return { x:x, y:y };
   },

   /**
    *  Mozilla did not report all of the parents up the hierarchy via the
    *  offsetParent property that IE did.  So for the calculation of the
    *  offsets we use the offsetParent property, but for the calculation of
    *  the scrollTop/scrollLeft adjustments we navigate up via the parentNode
    *  property instead so as to get the scroll offsets...
    *
    **/
   _toAbsoluteMozilla: function(element,accountForDocScroll) {
      var x = 0;
      var y = 0;
      var parent = element;
      while ( parent ) {
         x += parent.offsetLeft;
         y += parent.offsetTop;
         parent = parent.offsetParent;
      }

      parent = element;
      while ( parent &&
              parent != document.body &&
              parent != document.documentElement ) {
         if ( parent.scrollLeft  )
            x -= parent.scrollLeft;
         if ( parent.scrollTop )
            y -= parent.scrollTop;
         parent = parent.parentNode;
      }

      if ( accountForDocScroll ) {
         x -= this.docScrollLeft();
         y -= this.docScrollTop();
      }

      return { x:x, y:y };
   },

   docScrollLeft: function() {
      if ( window.pageXOffset )
         return window.pageXOffset;
      else if ( document.documentElement && document.documentElement.scrollLeft )
         return document.documentElement.scrollLeft;
      else if ( document.body )
         return document.body.scrollLeft;
      else
         return 0;
   },

   docScrollTop: function() {
      if ( window.pageYOffset )
         return window.pageYOffset;
      else if ( document.documentElement && document.documentElement.scrollTop )
         return document.documentElement.scrollTop;
      else if ( document.body )
         return document.body.scrollTop;
      else
         return 0;
   }

};