get items() {
      return this.content.map((item, idx) => {
        const visible = this.isItemInViewport(idx);
        return {
          id: `${this._id}-carousel-item-${idx + 1}`,
          item,
          tabIndex: visible ? "0" : "-1",
          posinset: `${idx + 1}`,
          setsize: `${this.content.length}`,
          styles: {
            width: `${this._itemWidth || 0}px`
          },
          classes: visible ? "" : "ui5-carousel-item--hidden"
        };
      });
    }
Assuming that all items have the same width
@private