dom.js

一个使用yui-ext库

                    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'
                    delta[1] = (style_pos == 'relative') ? 0 : el.offsetTop;
                } 
        
                if (pos[0] !== null) { el.style.left = pos[0] - pageXY[0] + delta[0] + 'px'; }
                if (pos[1] !== null) { el.style.top = pos[1] - pageXY[1] + delta[1] + 'px'; }
              
                if (!noRetry) {
                    var newXY = this.getXY(el);

                    // if retry is true, try one more time if we miss 
                   if ( (pos[0] !== null && newXY[0] != pos[0]) || 
                        (pos[1] !== null && newXY[1] != pos[1]) ) {
                       this.setXY(el, pos, true);
                   }
                }        
        
            };
            
            Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Set the X position of an html element in page coordinates, regardless of how the element is positioned.
         * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
         * @method setX
         * @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 {Int} x The value to use as the X coordinate for the element(s).
         */
        setX: function(el, x) {
            Y.Dom.setXY(el, [x, null]);
        },
        
        /**
         * Set the Y position of an html element in page coordinates, regardless of how the element is positioned.
         * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
         * @method setY
         * @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 {Int} x To use as the Y coordinate for the element(s).
         */
        setY: function(el, y) {
            Y.Dom.setXY(el, [null, y]);
        },
        
        /**
         * Returns the region position of the given element.
         * The element must be part of the DOM tree to have a region (display:none or elements not appended return false).
         * @method getRegion
         * @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 {Region | Array} A Region or array of Region instances containing "top, left, bottom, right" member data.
         */
        getRegion: function(el) {
            var f = function(el) {
                var region = new Y.Region.getRegion(el);
                return region;
            };
            
            return Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Returns the width of the client (viewport).
         * @method getClientWidth
         * @deprecated Now using getViewportWidth.  This interface left intact for back compat.
         * @return {Int} The width of the viewable area of the page.
         */
        getClientWidth: function() {
            return Y.Dom.getViewportWidth();
        },
        
        /**
         * Returns the height of the client (viewport).
         * @method getClientHeight
         * @deprecated Now using getViewportHeight.  This interface left intact for back compat.
         * @return {Int} The height of the viewable area of the page.
         */
        getClientHeight: function() {
            return Y.Dom.getViewportHeight();
        },

        /**
         * Returns a array of HTMLElements with the given class.
         * For optimized performance, include a tag and/or root node when possible.
         * @method getElementsByClassName
         * @param {String} className The class name to match against
         * @param {String} tag (optional) The tag name of the elements being collected
         * @param {String | HTMLElement} root (optional) The HTMLElement or an ID to use as the starting point 
         * @return {Array} An array of elements that have the given class name
         */
        getElementsByClassName: function(className, tag, root) {
            var method = function(el) { return Y.Dom.hasClass(el, className); };
            return Y.Dom.getElementsBy(method, tag, root);
        },

        /**
         * Determines whether an HTMLElement has the given className.
         * @method hasClass
         * @param {String | HTMLElement | Array} el The element or collection to test
         * @param {String} className the class name to search for
         * @return {Boolean | Array} A boolean value or array of boolean values
         */
        hasClass: function(el, className) {
            var re = new RegExp('(?:^|\\s+)' + className + '(?:\\s+|$)');
            
            var f = function(el) {
                return re.test(el['className']);
            };
            
            return Y.Dom.batch(el, f, Y.Dom, true);
        },
    
        /**
         * Adds a class name to a given element or collection of elements.
         * @method addClass         
         * @param {String | HTMLElement | Array} el The element or collection to add the class to
         * @param {String} className the class name to add to the class attribute
         */
        addClass: function(el, className) {
            var f = function(el) {
                if (this.hasClass(el, className)) { return; } // already present
                
                
                el['className'] = [el['className'], className].join(' ');
            };
            
            Y.Dom.batch(el, f, Y.Dom, true);
        },
    
        /**
         * Removes a class name from a given element or collection of elements.
         * @method removeClass         
         * @param {String | HTMLElement | Array} el The element or collection to remove the class from
         * @param {String} className the class name to remove from the class attribute
         */
        removeClass: function(el, className) {
            var re = new RegExp('(?:^|\\s+)' + className + '(?:\\s+|$)', 'g');

            var f = function(el) {
                if (!this.hasClass(el, className)) { return; } // not present
                
                
                var c = el['className'];
                el['className'] = c.replace(re, ' ');
                if ( this.hasClass(el, className) ) { // in case of multiple adjacent
                    this.removeClass(el, className);
                }
                
            };
            
            Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Replace a class with another class for a given element or collection of elements.
         * If no oldClassName is present, the newClassName is simply added.
         * @method replaceClass  
         * @param {String | HTMLElement | Array} el The element or collection to remove the class from
         * @param {String} oldClassName the class name to be replaced
         * @param {String} newClassName the class name that will be replacing the old class name
         */
        replaceClass: function(el, oldClassName, newClassName) {
            if (oldClassName === newClassName) { // avoid infinite loop
                return false;
            }
            
            var re = new RegExp('(?:^|\\s+)' + oldClassName + '(?:\\s+|$)', 'g');

            var f = function(el) {
            
                if ( !this.hasClass(el, oldClassName) ) {
                    this.addClass(el, newClassName); // just add it if nothing to replace
                    return; // note return
                }
            
                el['className'] = el['className'].replace(re, ' ' + newClassName + ' ');

                if ( this.hasClass(el, oldClassName) ) { // in case of multiple adjacent
                    this.replaceClass(el, oldClassName, newClassName);
                }
            };
            
            Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Generates a unique ID
         * @method generateId  
         * @param {String | HTMLElement | Array} el (optional) An optional element array of elements to add an ID to (no ID is added if one is already present).
         * @param {String} prefix (optional) an optional prefix to use (defaults to "yui-gen").
         * @return {String | Array} The generated ID, or array of generated IDs (or original ID if already present on an element)
         */
        generateId: function(el, prefix) {
            prefix = prefix || 'yui-gen';
            el = el || {};
            
            var f = function(el) {
                if (el) {
                    el = Y.Dom.get(el);
                } else {
                    el = {}; // just generating ID in this case
                }
                
                if (!el.id) {
                    el.id = prefix + id_counter++; 
                } // dont override existing
                
                
                return el.id;
            };
            
            return Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Determines whether an HTMLElement is an ancestor of another HTML element in the DOM hierarchy.
         * @method isAncestor
         * @param {String | HTMLElement} haystack The possible ancestor
         * @param {String | HTMLElement} needle The possible descendent
         * @return {Boolean} Whether or not the haystack is an ancestor of needle
         */
        isAncestor: function(haystack, needle) {
            haystack = Y.Dom.get(haystack);
            if (!haystack || !needle) { return false; }
            
            var f = function(needle) {
                if (haystack.contains && !isSafari) { // safari "contains" is broken
                    return haystack.contains(needle);
                }
                else if ( haystack.compareDocumentPosition ) {
                    return !!(haystack.compareDocumentPosition(needle) & 16);
                }
                else { // loop up and test each parent
                    var parent = needle.parentNode;
                    
                    while (parent) {
                        if (parent == haystack) {
                            return true;
                        }
                        else if (!parent.tagName || parent.tagName.toUpperCase() == 'HTML') {
                            return false;
                        }
                        
                        parent = parent.parentNode;
                    }
                    return false;
                }     
            };
            
            return Y.Dom.batch(needle, f, Y.Dom, true);      
        },
        
        /**
         * Determines whether an HTMLElement is present in the current document.
         * @method inDocument         
         * @param {String | HTMLElement} el The element to search for
         * @return {Boolean} Whether or not the element is present in the current document
         */
        inDocument: function(el) {
            var f = function(el) {
                return this.isAncestor(document.documentElement, el);
            };
            
            return Y.Dom.batch(el, f, Y.Dom, true);
        },
        
        /**
         * Returns a array of HTMLElements that pass the test applied by supplied boolean method.
         * For optimized performance, include a tag and/or root node when possible.
         * @method getElementsBy
         * @param {Function} method - A boolean method for testing elements which receives the element as its only argument.

         * @param {String} tag (optional) The tag name of the elements being collected
         * @param {String | HTMLElement} root (optional) The HTMLElement or an ID to use as the starting point 
         * @return {Array} Array of HTMLElements
         */
        getElementsBy: function(method, tag, root) {
            tag = tag || '*';
            
            var nodes = [];
            
            if (root) {
                root = Y.Dom.get(root);
                if (!root) { // if no root node, then no children
                    return nodes;
                }