build/dd-scroll/dd-scroll.js

	dd-scroll.js revision 5b05d3439409acca6a1bd01f011571161e705d8e
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark AndrewsYUI.add('dd-scroll', function(Y) {
11e9368a226272085c337e9e74b79808c16fbdbaTinderbox User
6a42ab64276ff832a47e009be1208f7c7d4da22dAutomatic Updater
6a42ab64276ff832a47e009be1208f7c7d4da22dAutomatic Updater    /**
4a14ce5ba00ab7bc55c99ffdcf59c7a4ab902721Automatic Updater     * Base scroller class used to create the Plugin.DDNodeScroll and Plugin.DDWinScroll.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * This class should not be called on it's own, it's designed to be a plugin.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * @module dd
6a42ab64276ff832a47e009be1208f7c7d4da22dAutomatic Updater     * @submodule dd-scroll
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    /**
6a42ab64276ff832a47e009be1208f7c7d4da22dAutomatic Updater     * Base scroller class used to create the Plugin.DDNodeScroll and Plugin.DDWinScroll.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * This class should not be called on it's own, it's designed to be a plugin.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * @class Scroll
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * @extends Base
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * @namespace DD
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     * @constructor
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews     */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    var S = function() {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        S.superclass.constructor.apply(this, arguments);
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt    },
cd32f419a8a5432fbb139f56ee73cbf68b9350ccTinderbox User    WS, NS,
f9aef05653eeb454c489d5bd2bde6daab774ad4aTinderbox User    HOST = 'host',
50066670817cdf9e86c832066d73715232b29680Tinderbox User    BUFFER = 'buffer',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    PARENT_SCROLL = 'parentScroll',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    WINDOW_SCROLL = 'windowScroll',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    SCROLL_TOP = 'scrollTop',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    SCROLL_LEFT = 'scrollLeft',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    OFFSET_WIDTH = 'offsetWidth',
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    OFFSET_HEIGHT = 'offsetHeight';
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews
f9aef05653eeb454c489d5bd2bde6daab774ad4aTinderbox User
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews    S.ATTRS = {
50066670817cdf9e86c832066d73715232b29680Tinderbox User        /**
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @attribute parentScroll
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @description Internal config option to hold the node that we are scrolling. Should not be set by the developer.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @type Node
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        parentScroll: {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            value: false,
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            setter: function(node) {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                if (node) {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    return node;
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                }
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                return false;
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            }
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        },
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @attribute buffer
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @description The number of pixels from the edge of the screen to turn on scrolling. Default: 30
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @type Number
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        buffer: {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            value: 30,
b27ce68bae92006e2ad7a9b75602c6385e529c3bAutomatic Updater            validator: Y.Lang.isNumber
922312472e2e05ebc64993d465999c5351b83036Automatic Updater        },
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        /**
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @attribute scrollDelay
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @description The number of milliseconds delay to pass to the auto scroller. Default: 235
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @type Number
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        scrollDelay: {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            value: 235,
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            validator: Y.Lang.isNumber
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        },
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @attribute host
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @description The host we are plugged into.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @type Object
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        host: {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            value: null
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        },
0e9e255d1643375056aa9ed7fe2a279713ffae78Automatic Updater        /**
cd791043c8a6edbcacc2392575a9816d19b8157cTinderbox User        * @attribute windowScroll
cd791043c8a6edbcacc2392575a9816d19b8157cTinderbox User        * @description Turn on window scroll support, default: false
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @type Boolean
481870b95fee976541f4fe455c0ef2dbeab3ec7aTinderbox User        */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        windowScroll: {
481870b95fee976541f4fe455c0ef2dbeab3ec7aTinderbox User            value: false,
481870b95fee976541f4fe455c0ef2dbeab3ec7aTinderbox User            validator: Y.Lang.isBoolean
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        },
e839bf134fb138920d4833cf05cb8b8906787a8dAutomatic Updater        /**
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @attribute vertical
e839bf134fb138920d4833cf05cb8b8906787a8dAutomatic Updater        * @description Allow vertical scrolling, default: true.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @type Boolean
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        vertical: {
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater            value: true,
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater            validator: Y.Lang.isBoolean
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        },
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @attribute horizontal
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        * @description Allow horizontal scrolling, default: true.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @type Boolean
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        */
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        horizontal: {
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater            value: true,
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater            validator: Y.Lang.isBoolean
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        }
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User    };
795a316ec568b2470aab18b9481443966047652eAutomatic Updater
795a316ec568b2470aab18b9481443966047652eAutomatic Updater    Y.extend(S, Y.Base, {
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt        /**
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        * @private
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        * @property _scrolling
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @description Tells if we are actively scrolling or not.
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        * @type Boolean
795a316ec568b2470aab18b9481443966047652eAutomatic Updater        */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        _scrolling: null,
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        /**
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @private
6478b87fd23bcd3ab74c25b261021fe19a239c4fTinderbox User        * @property _vpRegionCache
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @description Cache of the Viewport dims.
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @type Object
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
ca67ebfe9eef0b8f04179f7e511a19e0337a5422Automatic Updater        _vpRegionCache: null,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
ca67ebfe9eef0b8f04179f7e511a19e0337a5422Automatic Updater        * @private
ca67ebfe9eef0b8f04179f7e511a19e0337a5422Automatic Updater        * @property _dimCache
ca67ebfe9eef0b8f04179f7e511a19e0337a5422Automatic Updater        * @description Cache of the dragNode dims.
163af735c2082a024167be111d27bd5b5ff4f462Automatic Updater        * @type Object
481870b95fee976541f4fe455c0ef2dbeab3ec7aTinderbox User        */
481870b95fee976541f4fe455c0ef2dbeab3ec7aTinderbox User        _dimCache: null,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @private
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @property _scrollTimer
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @description Holder for the Timer object returned from Y.later.
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @type {Y.later}
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        _scrollTimer: null,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        /**
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @private
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        * @method _getVPRegion
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        * @description Sets the _vpRegionCache property with an Object containing the dims from the viewport.
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater        */
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        _getVPRegion: function() {
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater            var r = {},
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                n = this.get(PARENT_SCROLL),
6f1205897504b8f50b1785975482c995888dd630Tinderbox User            b = this.get(BUFFER),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            ws = this.get(WINDOW_SCROLL),
6f1205897504b8f50b1785975482c995888dd630Tinderbox User            xy = ((ws) ? [] : n.getXY()),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            w = ((ws) ? 'winWidth' : OFFSET_WIDTH),
6f1205897504b8f50b1785975482c995888dd630Tinderbox User            h = ((ws) ? 'winHeight' : OFFSET_HEIGHT),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            t = ((ws) ? n.get(SCROLL_TOP) : xy[1]),
6f1205897504b8f50b1785975482c995888dd630Tinderbox User            l = ((ws) ? n.get(SCROLL_LEFT) : xy[0]);
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            r = {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                top: t + b,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                right: (n.get(w) + l) - b,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                bottom: (n.get(h) + t) - b,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                left: l + b
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            };
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            this._vpRegionCache = r;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            return r;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        },
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        initializer: function() {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            var h = this.get(HOST);
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            h.after('drag:start', Y.bind(this.start, this));
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            h.after('drag:end', Y.bind(this.end, this));
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            h.on('drag:align', Y.bind(this.align, this));
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            //TODO - This doesn't work yet??
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            Y.one('win').on('scroll', Y.bind(function() {
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                this._vpRegionCache = null;
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User            }, this));
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        },
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        /**
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @private
b27ce68bae92006e2ad7a9b75602c6385e529c3bAutomatic Updater        * @method _checkWinScroll
922312472e2e05ebc64993d465999c5351b83036Automatic Updater        * @description Check to see if we need to fire the scroll timer. If scroll timer is running this will scroll the window.
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        * @param {Boolean} move Should we move the window. From Y.later
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User        */
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews        _checkWinScroll: function(move) {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            var r = this._getVPRegion(),
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                ho = this.get(HOST),
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                ws = this.get(WINDOW_SCROLL),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                xy = ho.lastXY,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                scroll = false,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                b = this.get(BUFFER),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                win = this.get(PARENT_SCROLL),
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                sTop = win.get(SCROLL_TOP),
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                sLeft = win.get(SCROLL_LEFT),
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                w = this._dimCache.w,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                h = this._dimCache.h,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                bottom = xy[1] + h,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                top = xy[1],
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User                right = xy[0] + w,
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                left = xy[0],
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                nt = top,
163af735c2082a024167be111d27bd5b5ff4f462Automatic Updater                nl = left,
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                st = sTop,
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                sl = sLeft;
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            if (this.get('horizontal')) {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                if (left <= r.left) {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    scroll = true;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    nl = xy[0] - ((ws) ? b : 0);
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    sl = sLeft - b;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                }
f9aef05653eeb454c489d5bd2bde6daab774ad4aTinderbox User                if (right >= r.right) {
cd32f419a8a5432fbb139f56ee73cbf68b9350ccTinderbox User                    scroll = true;
50066670817cdf9e86c832066d73715232b29680Tinderbox User                    nl = xy[0] + ((ws) ? b : 0);
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    sl = sLeft + b;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                }
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews            }
f9aef05653eeb454c489d5bd2bde6daab774ad4aTinderbox User            if (this.get('vertical')) {
f9aef05653eeb454c489d5bd2bde6daab774ad4aTinderbox User                if (bottom >= r.bottom) {
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    scroll = true;
50066670817cdf9e86c832066d73715232b29680Tinderbox User                    nt = xy[1] + ((ws) ? b : 0);
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    st = sTop + b;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                }
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                if (top <= r.top) {
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt                    scroll = true;
582f8b9a8d170a80ef67475bddb8ad5cf7cd7cadMark Andrews                    nt = xy[1] - ((ws) ? b : 0);
922312472e2e05ebc64993d465999c5351b83036Automatic Updater                    st = sTop - b;
                }
            }

            if (st < 0) {
                st = 0;
                nt = xy[1];
            }

            if (sl < 0) {
                sl = 0;
                nl = xy[0];
            }

            if (nt < 0) {
                nt = xy[1];
            }
            if (nl < 0) {
                nl = xy[0];
            }
            if (move) {
                ho.actXY = [nl, nt];
                ho._moveNode({ node: win, top: st, left: sl});
                if (!st && !sl) {
                    this._cancelScroll();
                }
            } else {
                if (scroll) {
                    this._initScroll();
                } else {
                    this._cancelScroll();
                }
            }
        },
        /**
        * @private
        * @method _initScroll
        * @description Cancel a previous scroll timer and init a new one.
        */
        _initScroll: function() {
            this._cancelScroll();
            this._scrollTimer = Y.Lang.later(this.get('scrollDelay'), this, this._checkWinScroll, [true], true);

        },
        /**
        * @private
        * @method _cancelScroll
        * @description Cancel a currently running scroll timer.
        */
        _cancelScroll: function() {
            this._scrolling = false;
            if (this._scrollTimer) {
                this._scrollTimer.cancel();
                delete this._scrollTimer;
            }
        },
        /**
        * @method align
        * @description Called from the drag:align event to determine if we need to scroll.
        */
        align: function(e) {
            if (this._scrolling) {
                this._cancelScroll();
                e.preventDefault();
            }
            if (!this._scrolling) {
                this._checkWinScroll();
            }
        },
        /**
        * @private
        * @method _setDimCache
        * @description Set the cache of the dragNode dims.
        */
        _setDimCache: function() {
            var node = this.get(HOST).get('dragNode');
            this._dimCache = {
                h: node.get(OFFSET_HEIGHT),
                w: node.get(OFFSET_WIDTH)
            };
        },
        /**
        * @method start
        * @description Called from the drag:start event
        */
        start: function() {
            this._setDimCache();
        },
        /**
        * @method end
        * @description Called from the drag:end event
        */
        end: function(xy) {
            this._dimCache = null;
            this._cancelScroll();
        }
    });

    Y.namespace('Plugin');


    /**
     * Extends the Scroll class to make the window scroll while dragging.
     * @class DDWindowScroll
     * @extends Scroll
     * @namespace Plugin
     * @constructor
     */
    WS = function() {
        WS.superclass.constructor.apply(this, arguments);
    };
    WS.ATTRS = Y.merge(S.ATTRS, {
        /**
        * @attribute windowScroll
        * @description Turn on window scroll support, default: true
        * @type Boolean
        */
        windowScroll: {
            value: true,
            setter: function(scroll) {
                if (scroll) {
                    this.set(PARENT_SCROLL, Y.one('win'));
                }
                return scroll;
            }
        }
    });
    Y.extend(WS, S, {
        //Shouldn't have to do this..
        initializer: function() {
            this.set('windowScroll', this.get('windowScroll'));
        }
    });
    /**
    * @property NS
    * @default winscroll
    * @readonly
    * @protected
    * @static
    * @description The Scroll instance will be placed on the Drag instance under the winscroll namespace.
    * @type {String}
    */
    WS.NAME = WS.NS = 'winscroll';
    Y.Plugin.DDWinScroll = WS;


    /**
     * Extends the Scroll class to make a parent node scroll while dragging.
     * @class DDNodeScroll
     * @extends Scroll
     * @namespace Plugin
     * @constructor
     */
    NS = function() {
        NS.superclass.constructor.apply(this, arguments);

    };
    NS.ATTRS = Y.merge(S.ATTRS, {
        /**
        * @attribute node
        * @description The node we want to scroll. Used to set the internal parentScroll attribute.
        * @type Node
        */
        node: {
            value: false,
            setter: function(node) {
                var n = Y.one(node);
                if (!n) {
                    if (node !== false) {
                        Y.error('DDNodeScroll: Invalid Node Given: ' + node);
                    }
                } else {
                    this.set(PARENT_SCROLL, n);
                }
                return n;
            }
        }
    });
    Y.extend(NS, S, {
        //Shouldn't have to do this..
        initializer: function() {
            this.set('node', this.get('node'));
        }
    });
    /**
    * @property NS
    * @default nodescroll
    * @readonly
    * @protected
    * @static
    * @description The NodeScroll instance will be placed on the Drag instance under the nodescroll namespace.
    * @type {String}
    */
    NS.NAME = NS.NS = 'nodescroll';
    Y.Plugin.DDNodeScroll = NS;

    Y.DD.Scroll = S;


}, '@VERSION@' ,{optional:['dd-proxy'], skinnable:false, requires:['dd-drag']});