title: Set and remove readonly property in ext Js
body: <p>In extJs I need to disable one field until edit button is clicked. </p>
  
  <pre><code>xtype:'textfield',
  fieldLabel: 'Address',
  name:'streetAddress',
  labelWidth: 48,                         
  maxLength: 100,                         
  cls: 'appAddresscls',
  id: 'resume-applicantdetails-view-address',
  allowBlank : false,
  //readOnly:true,
  skipValue:true
  </code></pre>
  
  <p>When loading I called</p>
  
  <pre><code>Ext.getCmp('resume-applicantdetails-view-address').getEl().dom.setAttribute('readOnly', true);
  </code></pre>
  
  <p>When editing </p>
  
  <pre><code>Ext.getCmp('resume-applicantdetails-view-address').getEl().dom.removeAttribute('readOnly');
  </code></pre>
  
  <p>But the field is always in edit mode. Actually I try this because, the disabled fields in IE appears in gray color.</p>