code: private int computeFirstCompletelyVisibleItemPositionForScrolledX(float[] starts) {
          if (lSCell == null || starts == null || starts.length <= 0) {
              return 0;
          }
          for (int i = 0; i < starts.length; i++) {
              if (starts[i] >= lSCell.currentDistance) {
                  return i;
              }
          }
          return starts.length - 1;
      }
docs: Find the first completely visible position.
  
  @param starts A recorder array to save each item's left position, including its margin.
  @return Position of first completely visible item.