title: extjs show validation when switching tabs
body: <p>HI,
  I hope somebody can help me here with the extjs framework.</p>
  
  <p>The problem I am having is that the field validation is not being rendered for the tabs that are not visibele on initialisation off the panel.</p>
  
  <p>It only starts working when clicking in the textfields.</p>
  
  <p>What I need is something to force the validation cue's for the fields on activating the tabs.</p>
  
  <p><strong>EDIT</strong>
  I came up with this</p>
  
  <pre><code>Ext.getCmp('aanMakenGebruikerTabPanel').on('tabchange',function(){
          AanMakenGebruikerWindow.syncShadow();
          Ext.getCmp('Mobiel1Veld').on('render',function(v){v.validate();});
          Ext.getCmp('Email1Veld').on('render',function(v){v.validate();});
          //console.log("[aanMakenGebruikerTabPanel] resize -- sync");
      });
  </code></pre>
  
  <p><strong>EDIT</strong>
  I SOLVED IT BY USING THE CASCADE FUNCTION SO IT ALSO REACHES ITEMS IN A FIELDSET.</p>
  
  <pre><code>Ext.getCmp('aanMakenGebruikerTabPanel').on('tabchange',function(tabPanel,tab){
          AanMakenGebruikerWindow.syncShadow();
          tab.cascade(function(item) {
     if (item.isFormField) {
      item.validate();
    }
  } );
      });
  </code></pre>
  
  <p>thanks, Richard</p>