title: sencha touch form - How to get field values when I click submit
body: <p>I new in sencha touch and I make a simple login form wichh accepts username and password from a user. When I click submit, The fields value of form will viewed in javascript alert in JSON format. I create my form in views application. Here's my code:</p>
  
  <pre class="lang-js prettyprint-override"><code>var formPanel = Ext.define('GS.view.Login', {
      extend: 'Ext.form.Panel',
      xtype: 'loginform',
  
      requires: [
          'Ext.form.FieldSet'],
  
      config: {
          title: 'Login',
          iconCls: 'home',
          url: 'authenticate_page.php',
          items: [{
              xtype: 'fieldset',
              title: 'Login',
  
              items: [{
                  xtype: 'textfield',
                  name: 'txt_username',
                  label: 'Username'
              }, {
                  xtype: 'passwordfield',
                  name: 'txt_password',
                  label: 'Password'
              }]
          }, {
              xtype: 'button',
              text: 'Allow me in',
              ui: 'confirm',
              handler: function () {
                  var values = this.getValues();
                  alert(values);
              }
          }]
      }
  });
  </code></pre>
  
  <p>I tried some ways but it isn't work. Please help.</p>