case BUTTON:
return new Button(env, ((IString) c.get(0)).getValue(),c.get(1), properties);
case CHECKBOX:
return new Checkbox(env, ((IString) c.get(0)).getValue(),((IBool)c.get(1)).getValue(), c.get(2), properties);
case CHOICE:
return new Choice(env, makeStringList((IList) c.get(0)), c.get(1), properties);
case COMBO: