title: ObjectChoiceField in blackberry
body: <p>In my application there is one <code>ObjectChoiceField</code> in <code>MainScreen</code></p>
  
  <p>i want to get <code>change Listner</code> of <code>ObjectChoiceField</code> after click on index 0. </p>
  
  <p>i had already get click event of ObjectChoiceField after click on index grater than 1 and so on .. 
  so how can i get instance click event after click on <code>ObjectChoiceField</code>  ?</p>