Ext combox listeners为什么总是显示第一值

Question

var storeList = new Ext.form.ComboBox({
                id:'transport',
                    store: ds,
                    fieldLabel: '交通工具',
                    allowBlank: false,
                    forceSelection: true,
                    valueField: id, // option.value
                    typeAhead: true,
                    displayField: 'name', // option.text
                    triggerAction: 'all',
                    emptyText: '请选择...',
                    mode: 'local',
                    selectOnFocus: true,
                    width: 135,
                    listeners:{
"select":function(){
alert(Ext.get("transport").dom.value); //获取id为combo的值为什么总是获取到第一值
}
}   
                });

Answer 1

var storeList = new Ext.form.ComboBox({
                id:'transport',
                    store: ds,
                    fieldLabel: '交通工具',
                    allowBlank: false,
                    forceSelection: true,
                    valueField: id,此处没加单引号，与store定义不一致 // option.value
                    typeAhead: true,
                    displayField: 'name', // option.text
                    triggerAction: 'all',
                    emptyText: '请选择...',
                    mode: 'local',
                    selectOnFocus: true,
                    width: 135,
                    listeners:{
"select":function(){
alert(Ext.get("transport").dom.value); //获取id为combo的值为什么总是获取到第一值
}
} 
                });

Answer 2

好像是EXT的一个BUG,郁闷！
COMBOX在失去焦点时会改变一次值，你可以监听change事件！