extjs中的fileuploadfield出现两个按钮

extjs中的fileuploadfield出现两个按钮，由于没有导入ext/3.0.0/examples/ux/FileUploadField.js样式

/**
 * @author edwin
 * @date 2011-1-30
 * @desc 上传窗体
 */
uploadWin = Ext.extend(Ext.Window,{
	id: 'upLoad',
	uploadPanel: null,
	constructor: function(){
		this.uploadPanel =  new Ext.form.FormPanel({
			fileUpload: true,//允许上传
			baseCls: 'x-plain',//作用在面板元素上的CSS样式类 （默认为 'x-panel')
			layout: 'form',
			labelWidth: 60,
			items: [{
				xtype: 'fileuploadfield',//引入插件
				fieldLabel: '上传照片',
				allowBlank: false,
				id: 'photo',
				buttonText: '选择'
			}]
			
	});
		//调用父类构造方法
		uploadWin.superclass.constructor.call(this,{
			title: '上传照片',
			modal: true,
			width: 380,
			height: 150,
			plain: true,
			items:[this.uploadPanel],
			buttonAlign: 'center',
			buttons:[{
				text: '确定'
			},{
				text: '取消'
			}]
		})
	}
})