关于EXT的combobox组件的奇怪问题,在线急等呀!!!!!!

   用EXT的ComboBox做的,可以运行,但是有一个奇怪问题是:当在下拉列表中选择了某一项后,输入框中显示的是"name"的值,可是焦点一离开,输入框的显示就变成"id"的值了. 帮助我找找原因吧,各位!十分感谢 
       var fm = Ext.form, Ed = Ext.grid.GridEditor;
   
    var storageidExt = new fm.ComboBox({
            fieldLabel: '入库仓库',
            hiddenName:'storageid',
            store: storageidStore,
            valueField:'id',
            displayField:'name',
            typeAhead: true,
            mode: 'local',
            triggerAction: 'all',
            emptyText:'请选择仓库...',
            selectOnFocus:true,
            width:200
        });
       
        var provideridExt = new fm.ComboBox({
            fieldLabel: '客户',
            hiddenName:'providerid',
            store: provideridStore,
            valueField:'id',
            displayField:'name',
            typeAhead: true,
            mode: 'local',
            triggerAction: 'all',
            emptyText:'请选择客户...',
            selectOnFocus:true,
            width:200
        });
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