title: Ext JS 4 checkboxfield not displayed
body: <p>has anyone else ran into a problem with ext js checkboxes not showing up?  We have tried everything, even download the architect software and it still won't display...  Any ideas?  </p>
  
  <p>I have a feeling it's like a css/include file we're missing, but I've looked all over the Internet and I still can't find a solution.</p>
  
  <pre><code> {
              xtype: 'checkboxfield',
              anchor: '100%',
              fieldLabel: 'Label2',
              boxLabel: 'Box Label2'
          }
  </code></pre>
  
  <p>Here's the panel:</p>
  
  <pre><code> var manForm = Ext.create('Ext.form.Panel', {
                  width: 800,
                  style: 'position: relative; left: 20px;',
                  renderTo: Ext.getBody(),
                  id: 'man_form',
                  title: 'Mobile Information',
                  waitMsgTarget: true,
                  fieldDefaults: {
                      labelAlign: 'right',
                      labelWidth: 85,
                      msgTarget: 'side'
                  },
                  items: [
                          {                       
                              xtype: 'container',
                             padding: '10px',
                           defaults: { height: 28 },
                              items: [{
                                            xtype: 'hiddenfield',
                                             name: 'id',
                                               id: 'id',
                                      },
                                      {
                                             xtype:'hiddenfield',
                                              name: 'item_id',
                                                id: 'item_id'
                                      },  
                                      {    xtype: 'container', 
                                          layout: 'hbox',  
                                        defaults: { height: 28 },
                                          margin: ' 0 10 0 0',
                                           items: [{
                                                         xtype:'textfield',
                                                    fieldLabel: 'Number',
                                                          name: 'ItemNumber',
                                                            id: 'ItemNumber',
                                                    labelWidth: 45,
                                                         width: 345, 
                                                     },
                                                     {
                                                         xtype:'textfield',
                                                    fieldLabel: 'Name',
                                                          name: 'ItemName',
                                                            id: 'ItemName',
                                                    labelWidth: 70,
                                                         width: 425,                                                  
                                                 }] 
                                      },
                                      {
                                             xtype: 'textfield',
                                        fieldLabel: 'Category List',
                                        labelWidth: 140,
                                             width: 700,
                                              name: 'CategoryList',
                                                id: 'CategoryList'
                                      },
                                      {
                                             xtype: 'textfield',
                                        fieldLabel: 'Short Desc For Cat List',
                                              name: 'ShortDescriptionForCategoryList',
                                                id: 'ShortDescriptionForCategoryList',
                                        labelWidth: 140,
                                             width: 600
                                      },
                                      {  xtype: 'container', 
                                        layout: 'hbox',  
                                        margin: ' 0 10 0 0',
                                         items: [{
                                                         xtype: 'textfield',                                        
                                                          name: 'BasePrice',
                                                    fieldLabel: 'Base Price',
                                                            id: 'BasePrice',
                                                    labelWidth: 140,
                                                         width: 270,
                                                         height: 28
                                                  },
                                                  {
                                                         xtype: 'textfield',                                        
                                                          name: 'RetailPrice',
                                                    fieldLabel: 'Retail Price',
                                                            id: 'RetailPrice',
                                                    labelWidth: 140,
                                                         width: 270,
                                                        height: 28
                                                },{
                  xtype: 'checkboxfield',
                  anchor: '100%',
                  fieldLabel: 'Label2',
                  boxLabel: 'Box Label2'
              }
  
  
                                                ] 
                                      },
                                      {
                                             xtype: 'textfield',                                        
                                              name: 'ItemImages',
                                        fieldLabel: 'Item Images',
                                                id: 'ItemImages',
                                        labelWidth: 140,
                                             width: 700                                                  
                                      },
                                      {
                                             xtype: 'textfield',                                        
                                              name: 'ItemPrimaryImageUrl',
                                        fieldLabel: 'Primary Image URL',
                                                id: 'ItemPrimaryImageUrl',
                                        labelWidth: 140,
                                             width: 700                                                   
                                      },                                     
                                      {
                                             xtype: 'textfield',                                        
                                              name: 'ItemPrimaryImageAltText',
                                        fieldLabel: 'Primary Image Alt Text',
                                                id: 'ItemPrimaryImageAltText',
                                        labelWidth: 140,
                                             width: 700                                                   
                                      }, 
                                      {
                                             xtype: 'textfield',                                        
                                              name: 'ItemThumbnailUrl',
                                        fieldLabel: 'Thumbnail URL',
                                                id: 'ItemThumbnailUrl',
                                        labelWidth: 140,
                                             width: 700                                                   
                                      }, 
                                      {
                                             xtype: 'textfield',                                        
                                              name: 'ItemThumbnailAltText',
                                        fieldLabel: 'Thumbnail Alt Text',
                                                id: 'ItemThumbnailAltText',
                                        labelWidth: 140,
                                             width: 700                                                   
                                      },                                         
                                      {
                                             xtype: 'button',
                                              text: 'Update',
                                              name: 'new_button',
                                                id: 'new_button',
                                             style: 'margin-left:720px; margin-bottom:5px',
                                           handler: function(event, toolEl, panel){
  
                                                Ext.Msg.show({
                                                     title:'Update Data',
                                                     msg: 'Are you sure you want to update these settings?',
                                                     buttons: Ext.Msg.YESNO,
                                                     icon: Ext.Msg.QUESTION,
                                                     fn: function(btn){
                                                       if (btn === 'yes'){
  
                                                         var obj = manForm.getForm().getValues();
                                                         for (var prop in obj) {
                                                           store.getAt(0).set(prop,obj[prop]);                
                                                          //alert(prop + " : " + obj[prop]);
                                                         }
  
                                                         store.update();
                                                         store.load();
                                                       }
                                                     }
                                                });
                                           }
                                    },
                           ]
  
                      }],
          });
  </code></pre>