Перемещение строк в Grid таблице ExtJs

modExtra.grid.Items = function (config) {
    config = config || {};

    Ext.applyIf(config, {
        .....
        remoteSort: true,
        enableDragDrop: true,
        ddGroup: 'modextra-grid-dd',
        ddAction: 'mgr/item/sort',
        ....
    });

    modExtra.grid.Items.superclass.constructor.call(this, config);
    ......
    if (config.enableDragDrop && config.ddAction) {
        this.on('render', function(grid) {
            grid._initDD(config);
        });
    }
};
Ext.extend(modExtra.grid.Items, MODx.grid.Grid, {
    .......
    _initDD: function (config) {
        var grid = this;
        var el = grid.getEl();

        new Ext.dd.DropTarget(el, {
            ddGroup: grid.ddGroup,
            notifyDrop: function (dd, e, data) {
                var store = grid.getStore();
                var target = store.getAt(dd.getDragData(e).rowIndex).id;
                var sources = [];
                if (data.selections.length < 1 || data.selections[0].id == target) {
                    return false;
                }
                for (var i in data.selections) {
                    if (!data.selections.hasOwnProperty(i)) {
                        continue;
                    }
                    var row = data.selections[i];
                    sources.push(row.id);
                }

                el.mask(_('loading'), 'x-mask-loading');
                MODx.Ajax.request({
                    url: config.url,
                    params: {
                        action: config.ddAction,
                        sources: Ext.util.JSON.encode(sources),
                        target: target,
                    },
                    listeners: {
                        success: {
                            fn: function () {
                                el.unmask();
                                grid.refresh();
                                if (typeof(grid.reloadTree) == 'function') {
                                    sources.push(target);
                                    grid.reloadTree(sources);
                                }
                            }, scope: grid
                        },
                        failure: {
                            fn: function () {
                                el.unmask();
                            }, scope: grid
                        },
                    }
                });
            },
        });
    }
});

Ext.reg('modextra-grid-items', modExtra.grid.Items);