EXT-JS adding elements dynamically into FormPanel

I have a FormPanel that includes a bunch of TextField, I also add more to it dynamically using FormPanel.add(), FormPanel.doLayout(), however the height doesn't readjust itself, so extra textfields are not visible. what's going on? thanks

From stackoverflow

• Either the FormPanel (and all higher level containers) have to be auto height (autoHeight: true) so that the browser will handle sizing, or else you will need to recalculate the height after adding and set it programmatically. I've done it both ways, depending on the layout.