直接设置labelWidth属性,但是要注意一点,这个属性要设置在FormPanel中而不是items中,例如

   
   
   
   
  1. var reorm = new Ext.form.FormPanel({ 
  2.                 autoHeight : true, 
  3.                 id : '_id', 
  4.                 url:'', 
  5.                 width : 500, 
  6.              height:450, 
  7.                 border: false, 
  8.                 labelWidth:40,//要设置在这里 
  9.                 items: [{ 
  10.                     layout:'column', 
  11.                     columnWidth:1, 
  12.                     items: [{ 
  13.                         layout:'form', 
  14.                         border:false, 
  15.                         items:[{ 
  16.                         xtype : 'textfield', 
  17.                         fieldLabel: '测试', 
  18.                         id:'_aaa', 
  19.                         readOnly:true, 
  20.                         columnWidth:.9, 
  21.                         width:200, 
  22.                         name:'aaa 
  23.                         }] 
  24.                     }