Method setupMutationObserver

src/core/a-node.js:163–178

* With custom elements V1 attributeChangedCallback only fires * for attributes defined statically via observedAttributes. * One can assign any arbitrary components to an A-Frame entity * hence we can't know the list of attributes beforehand. * This function setup a mutation observer to k

()

   * in the DOM and update components accordingly.
   */
  setupMutationObserver () {
    var self = this;
    var observerConfig = {attributes: true, attributeOldValue: true};
    var observer = new MutationObserver(function callAttributeChangedCallback (mutationList) {
      var i;
      for (i = 0; i < mutationList.length; i++) {
        if (mutationList[i].type === 'attributes') {
          var attributeName = mutationList[i].attributeName;
          var newValue = window.HTMLElement.prototype.getAttribute.call(self, attributeName);
          var oldValue = mutationList[i].oldValue;
          self.attributeChangedCallback(attributeName, oldValue, newValue);
        }
      }
    });
    observer.observe(this, observerConfig);
  }

  getChildren () {
    return Array.prototype.slice.call(this.children, 0);