<p>i've created a Form Panel, and i'm rendering couple of Combo Boxes in the panel with a store which is populated via an response handler.
the problem if i want to render the panel again it renders the combo boxes without the store, though i'm re-constructing the panel.
i tried to debug to figure out the cause and surprisingly though for combo box the Store is null on calling - comboBox.setStore(store) it checks for the property (isRendered) and finds it to be true and hence doesn't add the store but just keep the existing store which is still null.</p>

<p>i've seen this problem in another scenaio where i had created a collapsible field set containing the Combobox, On minimize and maximize of the fieldset the store vanishes for the same reasons.</p>

<p>can someone please help me here, i'm completely struck here i tried various option but nothing works.</p>

Have you tried
```
doLayout()
```
method of
```
FormPanel
```
?