element.scroll.js

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/*
 * Ext JS Library 3.0 Pre-alpha
 * Copyright(c) 2006-2008, Ext JS, LLC.
 * [e-mail]
 * 
 * http://extjs.com/license
 */

/**
 * @class Ext.Element
 */
Ext.Element.addMethods({
    /**
     * Returns true if this element is scrollable.
     * @return {Boolean}
     */
    isScrollable : function(){
        var dom = this.dom;
        return dom.scrollHeight > dom.clientHeight || dom.scrollWidth > dom.clientWidth;
    },

    /**
     * Scrolls this element the specified scroll point. It does NOT do bounds checking so if you scroll to a weird value it will try to do it. For auto bounds checking, use scroll().
     * @param {String} side Either "left" for scrollLeft values or "top" for scrollTop values.
     * @param {Number} value The new scroll value
     * @param {Boolean/Object} animate (optional) true for the default animation or a standard Element animation config object
     * @return {Element} this
     */
    scrollTo : function(side, value){
        this.dom["scroll" + (/top/i.test(side) ? "Top" : "Left")] = value;        
        return this;
    },
    
    /**
     * Returns the current scroll position of the element.
     * @return {Object} An object containing the scroll position in the format {left: (scrollLeft), top: (scrollTop)}
     */
    getScroll : function(){
        var d = this.dom, 
        	doc = document,
        	body = doc.body,
        	docElement = doc.documentElement,
        	l,
        	t,
        	ret;
        	
        if(d == doc || d == body){            
            if(Ext.isIE && Ext.isStrict){
                l = docElement.scrollLeft; 
                t = docElement.scrollTop;
            }else{
                l = window.pageXOffset;
                t = window.pageYOffset;
            }            
            ret = {left: l || (body ? body.scrollLeft : 0), top: t || (body ? body.scrollTop : 0)};
        }else{
            ret = {left: d.scrollLeft, top: d.scrollTop};
        }
        return ret;
    }
});