在Extjs中应用水平滚动

Question

我想在我的面板中应用水平滚动条（ExtJS） 我的代码是......

var reportPanel = new Wtf.Panel({
    border: false,
    title: "Chart View",
    autoScroll: true,
    iconCls: "pwndCRM piechartIcon",
    bodyStyle: 'background:white',
    layout: 'border',
    tbar: [this.pieChartButton, this.barChartButton],
    closable: true,
    items: [new Wtf.Panel({
        id: mainpanid + "center_panel",
        autoScroll: true,
        //columnWidth:.47,
        layout: "fit",
        border: true,
        region: "center",
        width: '50%',
        collapsible: true
    })
      , new Wtf.Panel({
        id: mainpanid + "east_panel",
        autoScroll: true,
        border: true,
        layout: "fit",
        //columnWidth:.48,
        region: "east",
        width: '50%',
        collapsible: true

    })
    ]
});

任何人都可以告诉代码有什么问题吗？