ExtJS4: from which class to derive?

Question

I'm working on custom component, which will contain combo and displayfield. It's supposed to be a combobox with validation message next to it. I'm wondering, from which base class to derive that one in order to have such functionality like store binding ect?

Answer 1

Eventually I found that it can be a simple Ext.panel.Panel.

Answer 2

Why don't you use standard ExtJs validation mechanism? It will produce exact outcome you want - a label next to the combobox.