protected void onUiEngineAttached(boolean attached) {
    if (_list != null) {
      this.invalidate();
      // fieldManager.invalidate();
      _list.invalidate();
    }

    super.onUiEngineAttached(attached);
  }
 public void fieldChanged(Field field, int context) {
   //		Dialog.alert("test");
   if (!(field instanceof MyButtonField)) {
     super.fieldChanged(field, context);
     return;
   }
   MyButtonField btnField = (MyButtonField) field;
   if (btnField == nextBT) {
     //			Dialog.alert("next");
     currentIndex = currentIndex + Const.NUM_LIST;
     UiApplication.getUiApplication().pushScreen(WaitScreen.getInstance());
     Engine.getInstance().getDocument(currentIndex, search);
   } else if (btnField == previousBT) {
     //			Dialog.alert("prev");
     currentIndex = currentIndex - Const.NUM_LIST;
     UiApplication.getUiApplication().pushScreen(WaitScreen.getInstance());
     Engine.getInstance().getDocument(currentIndex, search);
   } else if (btnField == searchBT) {
     search = searchTextField.getText();
     UiApplication.getUiApplication().pushScreen(WaitScreen.getInstance());
     Engine.getInstance().getDocument(currentIndex, search);
   }
 }