dom-debug.js

很棒的在线教学系统

         * @param {HTMLDocument} document (optional) The document to get the scroll value of
         * @return {Int}  The amount that the document is scrolled to the left
         */
        getDocumentScrollLeft: function(doc) {
            doc = doc || document;
            return Math.max(doc.documentElement.scrollLeft, doc.body.scrollLeft);
        }, 

        /**
         * Returns the top scroll value of the document 
         * @method getDocumentScrollTop
         * @param {HTMLDocument} document (optional) The document to get the scroll value of
         * @return {Int}  The amount that the document is scrolled to the top
         */
        getDocumentScrollTop: function(doc) {
            doc = doc || document;
            return Math.max(doc.documentElement.scrollTop, doc.body.scrollTop);
        },

        /**
         * Inserts the new node as the previous sibling of the reference node 
         * @method insertBefore
         * @param {String | HTMLElement} newNode The node to be inserted
         * @param {String | HTMLElement} referenceNode The node to insert the new node before 
         * @return {HTMLElement} The node that was inserted (or null if insert fails) 
         */
        insertBefore: function(newNode, referenceNode) {
            newNode = Y.Dom.get(newNode); 
            referenceNode = Y.Dom.get(referenceNode); 
            
            if (!newNode || !referenceNode || !referenceNode.parentNode) {
                YAHOO.log('insertAfter failed: missing or invalid arg(s)', 'error', 'Dom');
                return null;
            }       

            return referenceNode.parentNode.insertBefore(newNode, referenceNode); 
        },

        /**
         * Inserts the new node as the next sibling of the reference node 
         * @method insertAfter
         * @param {String | HTMLElement} newNode The node to be inserted
         * @param {String | HTMLElement} referenceNode The node to insert the new node after 
         * @return {HTMLElement} The node that was inserted (or null if insert fails) 
         */
        insertAfter: function(newNode, referenceNode) {
            newNode = Y.Dom.get(newNode); 
            referenceNode = Y.Dom.get(referenceNode); 
            
            if (!newNode || !referenceNode || !referenceNode.parentNode) {
                YAHOO.log('insertAfter failed: missing or invalid arg(s)', 'error', 'Dom');
                return null;
            }       

            if (referenceNode.nextSibling) {
                return referenceNode.parentNode.insertBefore(newNode, referenceNode.nextSibling); 
            } else {
                return referenceNode.parentNode.appendChild(newNode);
            }
        },

        /**
         * Creates a Region based on the viewport relative to the document. 
         * @method getClientRegion
         * @return {Region} A Region object representing the viewport which accounts for document scroll
         */
        getClientRegion: function() {
            var t = Y.Dom.getDocumentScrollTop(),
                l = Y.Dom.getDocumentScrollLeft(),
                r = Y.Dom.getViewportWidth() + l,
                b = Y.Dom.getViewportHeight() + t;

            return new Y.Region(t, r, b, l);
        }
    };
    
    var getXY = function() {
        if (document.documentElement.getBoundingClientRect) { // IE
            return function(el) {
                var box = el.getBoundingClientRect(),
                    round = Math.round;

                var rootNode = el.ownerDocument;
                return [round(box.left + Y.Dom.getDocumentScrollLeft(rootNode)), round(box.top +
                        Y.Dom.getDocumentScrollTop(rootNode))];
            };
        } else {
            return function(el) { // manually calculate by crawling up offsetParents
                var pos = [el.offsetLeft, el.offsetTop];
                var parentNode = el.offsetParent;

                // safari: subtract body offsets if el is abs (or any offsetParent), unless body is offsetParent
                var accountForBody = (isSafari &&
                        Y.Dom.getStyle(el, 'position') == 'absolute' &&
                        el.offsetParent == el.ownerDocument.body);

                if (parentNode != el) {
                    while (parentNode) {
                        pos[0] += parentNode.offsetLeft;
                        pos[1] += parentNode.offsetTop;
                        if (!accountForBody && isSafari && 
                                Y.Dom.getStyle(parentNode,'position') == 'absolute' ) { 
                            accountForBody = true;
                        }
                        parentNode = parentNode.offsetParent;
                    }
                }

                if (accountForBody) { //safari doubles in this case
                    pos[0] -= el.ownerDocument.body.offsetLeft;
                    pos[1] -= el.ownerDocument.body.offsetTop;
                } 
                parentNode = el.parentNode;

                // account for any scrolled ancestors
                while ( parentNode.tagName && !patterns.ROOT_TAG.test(parentNode.tagName) ) 
                {
                    if (parentNode.scrollTop || parentNode.scrollLeft) {
                        pos[0] -= parentNode.scrollLeft;
                        pos[1] -= parentNode.scrollTop;
                    }
                    
                    parentNode = parentNode.parentNode; 
                }

                return pos;
            };
        }
    }() // NOTE: Executing for loadtime branching
})();
/**
 * A region is a representation of an object on a grid.  It is defined
 * by the top, right, bottom, left extents, so is rectangular by default.  If 
 * other shapes are required, this class could be extended to support it.
 * @namespace YAHOO.util
 * @class Region
 * @param {Int} t the top extent
 * @param {Int} r the right extent
 * @param {Int} b the bottom extent
 * @param {Int} l the left extent
 * @constructor
 */
YAHOO.util.Region = function(t, r, b, l) {

    /**
     * The region's top extent
     * @property top
     * @type Int
     */
    this.top = t;
    
    /**
     * The region's top extent as index, for symmetry with set/getXY
     * @property 1
     * @type Int
     */
    this[1] = t;

    /**
     * The region's right extent
     * @property right
     * @type int
     */
    this.right = r;

    /**
     * The region's bottom extent
     * @property bottom
     * @type Int
     */
    this.bottom = b;

    /**
     * The region's left extent
     * @property left
     * @type Int
     */
    this.left = l;
    
    /**
     * The region's left extent as index, for symmetry with set/getXY
     * @property 0
     * @type Int
     */
    this[0] = l;
};

/**
 * Returns true if this region contains the region passed in
 * @method contains
 * @param  {Region}  region The region to evaluate
 * @return {Boolean}        True if the region is contained with this region, 
 *                          else false
 */
YAHOO.util.Region.prototype.contains = function(region) {
    return ( region.left   >= this.left   && 
             region.right  <= this.right  && 
             region.top    >= this.top    && 
             region.bottom <= this.bottom    );

    // this.logger.debug("does " + this + " contain " + region + " ... " + ret);
};

/**
 * Returns the area of the region
 * @method getArea
 * @return {Int} the region's area
 */
YAHOO.util.Region.prototype.getArea = function() {
    return ( (this.bottom - this.top) * (this.right - this.left) );
};

/**
 * Returns the region where the passed in region overlaps with this one
 * @method intersect
 * @param  {Region} region The region that intersects
 * @return {Region}        The overlap region, or null if there is no overlap
 */
YAHOO.util.Region.prototype.intersect = function(region) {
    var t = Math.max( this.top,    region.top    );
    var r = Math.min( this.right,  region.right  );
    var b = Math.min( this.bottom, region.bottom );
    var l = Math.max( this.left,   region.left   );
    
    if (b >= t && r >= l) {
        return new YAHOO.util.Region(t, r, b, l);
    } else {
        return null;
    }
};

/**
 * Returns the region representing the smallest region that can contain both
 * the passed in region and this region.
 * @method union
 * @param  {Region} region The region that to create the union with
 * @return {Region}        The union region
 */
YAHOO.util.Region.prototype.union = function(region) {
    var t = Math.min( this.top,    region.top    );
    var r = Math.max( this.right,  region.right  );
    var b = Math.max( this.bottom, region.bottom );
    var l = Math.min( this.left,   region.left   );

    return new YAHOO.util.Region(t, r, b, l);
};

/**
 * toString
 * @method toString
 * @return string the region properties
 */
YAHOO.util.Region.prototype.toString = function() {
    return ( "Region {"    +
             "top: "       + this.top    + 
             ", right: "   + this.right  + 
             ", bottom: "  + this.bottom + 
             ", left: "    + this.left   + 
             "}" );
};

/**
 * Returns a region that is occupied by the DOM element
 * @method getRegion
 * @param  {HTMLElement} el The element
 * @return {Region}         The region that the element occupies
 * @static
 */
YAHOO.util.Region.getRegion = function(el) {
    var p = YAHOO.util.Dom.getXY(el);

    var t = p[1];
    var r = p[0] + el.offsetWidth;
    var b = p[1] + el.offsetHeight;
    var l = p[0];

    return new YAHOO.util.Region(t, r, b, l);
};

/////////////////////////////////////////////////////////////////////////////


/**
 * A point is a region that is special in that it represents a single point on 
 * the grid.
 * @namespace YAHOO.util
 * @class Point
 * @param {Int} x The X position of the point
 * @param {Int} y The Y position of the point
 * @constructor
 * @extends YAHOO.util.Region
 */
YAHOO.util.Point = function(x, y) {
   if (YAHOO.lang.isArray(x)) { // accept input from Dom.getXY, Event.getXY, etc.
      y = x[1]; // dont blow away x yet
      x = x[0];
   }
   
    /**
     * The X position of the point, which is also the right, left and index zero (for Dom.getXY symmetry)
     * @property x
     * @type Int
     */

    this.x = this.right = this.left = this[0] = x;
     
    /**
     * The Y position of the point, which is also the top, bottom and index one (for Dom.getXY symmetry)
     * @property y
     * @type Int
     */
    this.y = this.top = this.bottom = this[1] = y;
};

YAHOO.util.Point.prototype = new YAHOO.util.Region();

YAHOO.register("dom", YAHOO.util.Dom, {version: "2.6.0", build: "1321"});