title: Set focus on Extjs textfield
body: <p>Currently I got problem with setting focus on extjs textfield. When form show, I want to set focus to First name text box and I try to use build in function focus() but still can't make it work.
  I am happy to see your suggestion.</p>
  
  <pre><code>var simple = new Ext.FormPanel({
  
      labelWidth: 75, 
      url:'save-form.php',
      frame:true,
      title: 'Simple Form',
      bodyStyle:'padding:5px 5px 0',
      width: 350,
      defaults: {width: 230},
      defaultType: 'textfield',
      items: [{
              fieldLabel: 'First Name',
              name: 'first',
              id: 'first_name',
              allowBlank:false
          },{
              fieldLabel: 'Last Name',
              name: 'last'
          },{
              fieldLabel: 'Company',
              name: 'company'
          }, {
              fieldLabel: 'Email',
              name: 'email',
              vtype:'email'
          }, new Ext.form.TimeField({
              fieldLabel: 'Time',
              name: 'time',
              minValue: '8:00am',
              maxValue: '6:00pm'
          })
      ],
  
      buttons: [{
          text: 'Save'
      },{
          text: 'Cancel'
      }]
  });
  
  simple.render(document.body);
  </code></pre>