ExtJs 3.x以编程方式滚动ListView

Ext.onReady(function(){
    var store = new Ext.data.JsonStore({
        fields: [\'name\', \'url\', {name:\'size\', type: \'float\'}, {name:\'lastmod\', type:\'date\', dateFormat:\'timestamp\'}],
        data : [{\"name\":\"dance_fever.jpg\",\"size\":2067,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/dance_fever.jpg\"}
                ,{\"name\":\"gangster_zack.jpg\",\"size\":2115,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/gangster_zack.jpg\"}
                ,{\"name\":\"kids_hug.jpg\",\"size\":2477,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/kids_hug.jpg\"}
                ,{\"name\":\"kids_hug2.jpg\",\"size\":2476,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/kids_hug2.jpg\"}
                ,{\"name\":\"sara_pink.jpg\",\"size\":2154,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/sara_pink.jpg\"}
                ,{\"name\":\"sara_pumpkin.jpg\",\"size\":2588,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/sara_pumpkin.jpg\"}
                ,{\"name\":\"sara_smile.jpg\",\"size\":2410,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/sara_smile.jpg\"}
                ,{\"name\":\"up_to_something.jpg\",\"size\":2120,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/up_to_something.jpg\"}
                ,{\"name\":\"zack.jpg\",\"size\":2901,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/zack.jpg\"}
                ,{\"name\":\"zacks_grill.jpg\",\"size\":2825,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/zacks_grill.jpg\"}
                ,{\"name\":\"zack_dress.jpg\",\"size\":2645,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/zack_dress.jpg\"}
                ,{\"name\":\"zack_hat.jpg\",\"size\":2323,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/zack_hat.jpg\"}
                ,{\"name\":\"zack_sink.jpg\",\"size\":2303,\"lastmod\":1265631056000,\"url\":\"images\\/thumbs\\/zack_sink.jpg\"}]
    });

    var listView = new Ext.list.ListView({
        id      : \'listview\',
        store: store,
        multiSelect: true,
        emptyText: \'No images to display\',
        columns: [{
            header: \'File\',
            width: .45,
            dataIndex: \'name\'
        },{
            header: \'Last Modified\',
            xtype: \'datecolumn\',
            format: \'m-d h:i a\',
            width: .3, 
            dataIndex: \'lastmod\'
        },{
            header: \'Size\',
            dataIndex: \'size\',
            tpl: \'{size:fileSize}\',
            align: \'right\',
            cls: \'listview-filesize\'
        }]
    });

    // put it in a Panel so it looks pretty
    var panel = new Ext.Panel({
        id:\'images-view\',
        width:425,
        height:250,
        collapsible:true,
        resizable : true,
        layout:\'fit\',
        title:\'Simple ListView <i>(0 items selected)</i>\',
        items: listView
    });
    panel.render(document.body);
});