Extjs3 动态panel

this.dynamicPanel = new Ext.Panel({
            region: 'center',
            frame: false,
            border: false,
            layout:'fit',
            items:[
                this.createDynamicPanel('Retailers')
            ]
        });

createDynamicPanel:function(panelType){
        if(panelType=='Retailers'){
            return new Ext.ux.RetailersPanel();
        }
    },
    onRetailersFire:function(){
        var dynamicPanel = this.dynamicPanel;
        dynamicPanel.removeAll();    //移除panel中的所有元素
        dynamicPanel.add(this.createDynamicPanel('Retailers'));
        dynamicPanel.doLayout();    //重新渲染panel(Extjs4中直接添加即可,无需重新渲染)
    }