Acces buttons in Data Field app

Hi, 

I won't be particularly original if I say that I am a novice in creating applets for Connect IQ. I have a problem with accessing buttons in an app of type Data Field. In app of type Watch App there is no problem with this, button presses are captured (print). After changing to Data Field (WatchUi.View -> WatchUi.DataField), button presses are no longer captured. What needs to be changed to access buttons in a Data Field app?

Regards

WojciechW