getChildContext() {
    return {
      getIsSlotAdReady: this.getIsSlotAdReady,
      setIsSlotAdReady: this.setIsSlotAdReady,
      getIsComponentMounted: this.getIsComponentMounted,
      setIsComponentMounted: this.setIsComponentMounted,
      refreshAds: this.refreshAds,
      clearAdSlots: this.clearAdSlots,
    };
  }

propTypes: {
  /**
   * Enables or disables collapsing of slot divs so that they don't
   * take up any space on the page when there is no ad content to display.
   */
  collapseEmptyDivs: ProTypes.bool,

  /**
   * Event handler for slotRenderEnded event.
   */
  onSlotRenderEnded: PropTypes.func,
},

// example
handleSlotRenderEnded = (provider, event) => {
    const adElement = document.getElementById(`${event.slot.getSlotElementId()}-container`);

    switch (event.slot.getAdUnitPath()) {
      case AdProfiles.idleBannerCenter.path: {
        provider.setIsSlotAdReady(AdProfiles.idleBannerCenter.name, !event.isEmpty);
        break;
      }
      default:
        break;
    }

    if (event.isEmpty && adElement) {
      adElement.style.display = 'block';
    }
};

  // [300, 250], [[300, 250], 'fluid'], ['fluid]
  const SIZE_TYPE = PropTypes.arrayOf(
    PropTypes.oneOfType([PropTypes.arrayOf(PropTypes.number), PropTypes.string, PropTypes.number]),
  );


  /* if responsive break point is [0, 0] and [1300, 0] ([width, height])
  [
    [
      [0,0],
      [[1, 1], [650, 60], 'fluid'],
    ],
    [
      [1300, 0],
      [[1, 1], [800, 60], 'fluid']
    ]
  ]
  */
  const MULTI_SIZE_TYPE = PropTypes.arrayOf(PropTypes.arrayOf(AD_SIZE_TYPE));


  const ProfilePropType = PropTypes.shape({
    path: PropTypes.string,           // DFP code
    name: PropTypes.string,           // slot name
    size: SIZE_TYPE,                  // slot size
    multiSize: MULTI_SIZE_TYPE,       // responsive size mapping
    multiSizeHandler: PropTypes.func, // responsive handler
    waitingFor: PropTypes.string,     // refresh ads after component didmount
    hideOnInitial: PropTypes.bool,    // set display: none; on initial
  });

  propTypes: {
    // Profile data for slot
    profile: ProfilePropType.isRequired,

    // class name
    className: PropTypes.string,

    // Init slot after specific millisecond
    asyncInit: PropTypes.number,

    // use lazyLoading mode
    lazyLoading: PropTypes.bool,

    /**
     * `topOffset` can either be a number, in which case its a distance from the
     * top of the container in pixels, or a string value. Valid string values are
     * of the form "20px", which is parsed as pixels, or "20%", which is parsed
     * as a percentage of the height of the containing element.
     * For instance, if you pass "-20%", and the containing element is 100px tall,
     * then the waypoint will be triggered when it has been scrolled 20px beyond
     * the top of the containing element.
     */
    lazyLoadingTopOffset: PropTypes.oneOfType([PropTypes.number, PropTypes.string]),

    /**
     * `bottomOffset` is like `topOffset`, but for the bottom of the container.
     */
    lazyLoadingBottomOffset: PropTypes.oneOfType([PropTypes.number, PropTypes.string]),

    // DFP setTargeting
    targetValue: PropTypes.arrayOf(PropTypes.string),

  },