Method load

src/core/a-node.js:114–153

* Wait for children to load, if any. * Then emit `loaded` event and set `hasLoaded`.

(cb, childFilter)

   * Then emit `loaded` event and set `hasLoaded`.
   */
  load (cb, childFilter) {
    var children;
    var childrenLoaded;
    var self = this;

    if (this.hasLoaded) { return; }

    // Default to waiting for all nodes.
    childFilter = childFilter || isANode;
    // Wait for children to load (if any), then load.
    children = this.getChildren();
    childrenLoaded = children.filter(childFilter).map(function (child) {
      return new Promise(function waitForLoaded (resolve, reject) {
        if (child.hasLoaded) { return resolve(); }
        child.addEventListener('loaded', resolve);
        child.addEventListener('error', reject);
      });
    });

    Promise.allSettled(childrenLoaded).then(function emitLoaded (results) {
      results.forEach(function checkResultForError (result) {
        if (result.status === 'rejected') {
          // An "error" event has already been fired by THREE.js loader,
          // so we don't need to fire another one.
          // A warning explaining the consequences of the error is sufficient.
          warn('Rendering scene with errors on node: ', result.reason.target);
        }
      });

      self.isLoading = true;
      self.setupMutationObserver();
      if (cb) { cb(); }
      self.isLoading = false;
      self.hasLoaded = true;
      // loaded-private is an event analog to loaded that gives A-Frame an opportunity to manage internal
      // affairs before the publicly loaded event fires and corresponding handlers executed.
      self.emit('loaded-private', undefined, false);
      self.emit('loaded', undefined, false);
    });
  }

  /**
   * With custom elements V1 attributeChangedCallback only fires