title: extjs radiogroup before change event
body: <p>Could you please help me before change/check the event on ExtJS radiogroup. I want some event should check before changing the radio button based on the condition. I need to allow user to change the select another radio button if condition says false, then we need to select the old radio button only.</p>
  
  <p>Please refer the below code:</p>
  
  <pre><code>Ext.application({
      name: 'Fiddle',
      launch: function () {
          Ext.create('Ext.form.Panel', {
              title: 'RadioGroup Example',
              width: 300,
              height: 125,
              bodyPadding: 10,
              renderTo: Ext.getBody(),
              items: [{
                  xtype: 'radiogroup',
                  fieldLabel: 'Gender',
                  columns: 1,
                  items: [{
                      boxLabel: 'Male',
                      name: 'rb',
                      inputValue: '1'
                  }, {
                      boxLabel: 'Female',
                      name: 'rb',
                      inputValue: '2',
                  }],
                  listeners: {
                      change: function(field, newValue, oldValue, eOpts) {
                          console.log(newValue);
                          alert(newValue.rb);
                      },
                  }
              }]
          });
      }
  });
  </code></pre>
  
  <p><a href="https://fiddle.sencha.com/#view/editor&amp;fiddle/32fb" rel="nofollow noreferrer">https://fiddle.sencha.com/#view/editor&amp;fiddle/32fb</a></p>