EXTJS-textfield等组件宽度自适应

/**
*外部组件属性：layout: 'column'，内部组件属性：layout: 'form'并且加入defaults: {anchor:'90%'}属性
*/
var north = new Ext.FormPanel({
            region: 'north',
            margins: '0 0 2 0',
            cmargins: '0 0 2 0',
            formId: 'searchForm',
            frame:true,
            height: 100,
            width: '100%',
            defaults: {width: '100%'},
            collapsible:true,
            layout: 'column',//重点
            items:[{
                layout:'column',//重点
                columnWidth:.99,
                height: 25,
                border:false,
                labelSeparator:'：',
                items:[{
                    defaults: {anchor:'90%'},//设置此属性
                    columnWidth:.25,
                    layout: 'form',//重点
                    border:false,
                    items: [classifier]
                }]
            }],
            buttons : [{
                text : '查询',
                iconCls : 'btn_ico_query',
                handler : search
            }, {
                text : '重置',
                iconCls : 'btn_ico_remove',
                handler : clear
            }]
        });