Method rerender_

src/preact/base-element.js:611–769

@private

()

  /** @private */
  rerender_() {
    // If the component unmounted before the scheduled render runs, exit
    // early.
    if (!this.mounted_) {
      return;
    }

    const Ctor = /** @type {typeof PreactBaseElement} */ (
      /** @type {?} */ (this.constructor)
    );
    const {detached: isDetached, usesShadowDom: isShadow} = Ctor;
    const lightDomTag = isShadow ? null : Ctor.lightDomTag;

    if (!this.container_) {
      const doc = this.win.document;
      if (isShadow) {
        devAssert(
          !isDetached,
          'The AMP element cannot be rendered in detached mode ' +
            'when "props" are configured with "children" property.'
        );
        // Check if there's a pre-constructed shadow DOM.
        let {shadowRoot} = this.element;
        let container = shadowRoot && childElementByTag(shadowRoot, 'c');
        if (container) {
          this.hydrationPending_ = true;
        } else {
          // Create new shadow root.
          shadowRoot = this.element.attachShadow({
            mode: 'open',
            delegatesFocus: Ctor.delegatesFocus,
          });

          // The pre-constructed shadow root is required to have the stylesheet
          // inline. Thus, only the new shadow roots share the stylesheets.
          const {shadowCss} = Ctor;
          if (shadowCss) {
            installShadowStyle(shadowRoot, this.element.tagName, shadowCss);
          }

          // Create container.
          // The pre-constructed shadow root is required to have this container.
          container = createElementWithAttributes(
            doc,
            'c',
            SHADOW_CONTAINER_ATTRS
          );
          shadowRoot.appendChild(container);

          // Create a slot for internal service elements i.e. "i-amphtml-sizer".
          // The pre-constructed shadow root is required to have this slot.
          const serviceSlot = createElementWithAttributes(
            doc,
            'slot',
            SERVICE_SLOT_ATTRS
          );
          shadowRoot.appendChild(serviceSlot);
          this.getPlaceholder?.()?.setAttribute('slot', SERVICE_SLOT_NAME);