EXT textfield 输入框添加键盘监听事件

var searchText = new Ext.form.TextField({

     id:'searchText',

     name: 'searchText',

     value:'', width:'150',

    enableKeyEvents : true,

     //找来找去竟然没发现少了这个属性。。。。

     scope:this,

     listeners: {

            'keyup': { fn: function(o, evt) {

                           Ext.MessageBox.alert('----');

                                                            },

                           scope: this }

                       }

      });