title: Disable auto sorting on property grid in ExtJS
body: <p>I am dealing with property grid. I want to prevent auto sorting of column names for property grid.
  here is my code. Bold highlighted code is my source for property grid and its order is just like I want to see. But Ext is auto sorting column orders alphabeticly. How can I prevent that.</p>
  
  <p>Thanks for any suggestion.</p>
  
  <pre>
  Ext.ns('Application.propertygrid');
  Application.propertygrid.FileDetail = Ext.extend(Ext.grid.PropertyGrid, {
      title: 'File Detail',
      height: 200,
      border: false,
      stripeRows: true,
      flex: 1,
      initComponent: function () {
          Application.propertygrid.FileDetail.superclass.initComponent.apply(this, arguments);
      },
      <b>source: {
          Name: 'Please select a file',
          Type: 'Please select a file',
          Size: 'Please select a file',
          Path: 'Please select a file',
          FullPath: 'Please select a file',
          Width: 'Please select a file',
          Height: 'Please select a file'
      },</b>
      listeners: {
          beforeedit: function(){
              return false; // prevent editing 
          },
          headerclick: function(){
              return false; // prevent column sorting on click
          }
      }
  })
  Ext.reg('filedetail', Application.propertygrid.FileDetail);
  </pre>