dom.js

一个使用yui-ext库

/*
Copyright (c) 2007, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.net/yui/license.txt
version: 2.2.0
*/
/*
Copyright (c) 2006, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.net/yui/license.txt
*/

/**
 * The dom module provides helper methods for manipulating Dom elements.
 * @module dom
 *
 */

(function() {
    var Y = YAHOO.util,     // internal shorthand
        getStyle,           // for load time browser branching
        setStyle,           // ditto
        id_counter = 0,     // for use with generateId
        propertyCache = {}; // for faster hyphen converts
    
    // brower detection
    var ua = navigator.userAgent.toLowerCase(),
        isOpera = (ua.indexOf('opera') > -1),
        isSafari = (ua.indexOf('safari') > -1),
        isGecko = (!isOpera && !isSafari && ua.indexOf('gecko') > -1),
        isIE = (!isOpera && ua.indexOf('msie') > -1); 
    
    // regex cache
    var patterns = {
        HYPHEN: /(-[a-z])/i
    };

    
    var toCamel = function(property) {
        if ( !patterns.HYPHEN.test(property) ) {
            return property; // no hyphens
        }
        
        if (propertyCache[property]) { // already converted
            return propertyCache[property];
        }
        
        while( patterns.HYPHEN.exec(property) ) {
            property = property.replace(RegExp.$1,
                    RegExp.$1.substr(1).toUpperCase());
        }
        
        propertyCache[property] = 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
    };
    
    // branching at load instead of runtime
    if (document.defaultView && document.defaultView.getComputedStyle) { // W3C DOM method
        getStyle = function(el, property) {
            var value = null;
            
            var computed = document.defaultView.getComputedStyle(el, '');
            if (computed) { // test computed before touching for safari
                value = computed[toCamel(property)];
            }
            
            return el.style[property] || value;
        };
    } else if (document.documentElement.currentStyle && isIE) { // IE method
        getStyle = function(el, property) {                         
            switch( toCamel(property) ) {
                case 'opacity' :// IE opacity uses filter
                    var val = 100;
                    try { // will error if no DXImageTransform
                        val = el.filters['DXImageTransform.Microsoft.Alpha'].opacity;

                    } catch(e) {
                        try { // make sure its in the document
                            val = el.filters('alpha').opacity;
                        } catch(e) {
                        }
                    }
                    return val / 100;
                    break;
                default: 
                    // test currentStyle before touching
                    var value = el.currentStyle ? el.currentStyle[property] : null;
                    return ( el.style[property] || value );
            }
        };
    } else { // default to inline only
        getStyle = function(el, property) { return el.style[property]; };
    }
    
    if (isIE) {
        setStyle = function(el, property, val) {
            switch (property) {
                case 'opacity':
                    if ( 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
                        }
                    }
                    break;
                default:
                el.style[property] = val;
            }
        };
    } else {
        setStyle = function(el, property, val) {
            el.style[property] = val;
        };
    }
    
    /**
     * Provides helper methods for DOM elements.
     * @namespace YAHOO.util
     * @class Dom
     */
    YAHOO.util.Dom = {
        /**
         * Returns an HTMLElement reference.
         * @method get
         * @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] = Y.Dom.get(el[i]);
                }
                
                return collection;
            }

            return null; // safety, should never happen
        },
    
        /**
         * Normalizes currentStyle and ComputedStyle.
         * @method getStyle
         * @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) {
            property = toCamel(property);
            
            var f = function(element) {
                return getStyle(element, property);
            };
            
            return Y.Dom.batch(el, f, Y.Dom, true);
        },
    
        /**
         * Wrapper for setting style properties of HTMLElements.  Normalizes "opacity" across modern browsers.
         * @method setStyle
         * @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) {
            property = toCamel(property);
            
            var f = function(element) {
                setStyle(element, property, val);
                
            };
            
            Y.Dom.batch(el, f, Y.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).
         * @method getXY
         * @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.parentNode === null || 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 (Y.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 Y.Dom.batch(el, f, Y.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).
         * @method getX
         * @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 Y.Dom.getXY(el)[0];
            };
            
            return Y.Dom.batch(el, f, Y.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).
         * @method getY
         * @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 Y.Dom.getXY(el)[1];
            };
            
            return Y.Dom.batch(el, f, Y.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).
         * @method setXY
         * @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');