Method getSizeOfItem

src/react-list.js:428–450

(index)

  }

  getSizeOfItem(index) {
    const { cache, items } = this;
    const { axis, itemSizeGetter, itemSizeEstimator, type } = this.props;
    const { from, itemSize, size } = this.state;

    // Try the static itemSize.
    if (itemSize) return itemSize;

    // Try the itemSizeGetter.
    if (itemSizeGetter) return itemSizeGetter(index);

    // Try the cache.
    if (index in cache) return cache[index];

    // Try the DOM.
    if (type === 'simple' && index >= from && index < from + size && items) {
      const itemEl = items.children[index - from];
      if (itemEl) return itemEl[OFFSET_SIZE_KEYS[axis]];
    }

    // Try the itemSizeEstimator.
    if (itemSizeEstimator) return itemSizeEstimator(index, cache);
  }

  scrollTo(index) {
    if (index != null) this.setScroll(this.getSpaceBefore(index));