Method getOffset

src/react-list.js:169–176

(el)

  }

  getOffset(el) {
    const { axis } = this.props;
    let offset = el[CLIENT_START_KEYS[axis]] || 0;
    const offsetKey = OFFSET_START_KEYS[axis];
    do offset += el[offsetKey] || 0;
    while ((el = el.offsetParent));
    return offset;
  }

  getEl() {
    return this.el || this.items;