code: @Override
      protected boolean onRequestFocusInDescendants(int direction,
                                                    Rect previouslyFocusedRect) {
          int index;
          int increment;
          int end;
          int count = getChildCount();
          if ((direction & FOCUS_FORWARD) != 0) {
              index = 0;
              increment = 1;
              end = count;
          } else {
              index = count - 1;
              increment = -1;
              end = -1;
          }
          for (int i = index; i != end; i += increment) {
              View child = getChildAt(i);
              if (child.getVisibility() == VISIBLE) {
                  ItemInfo ii = infoForChild(child);
                  if (ii != null && ii.position == mCurItem) {
                      if (child.requestFocus(direction, previouslyFocusedRect)) {
                          return true;
                      }
                  }
              }
          }
          return false;
      }
docs: We only want the current page that is being shown to be focusable.