Method ensureLoaded

src/custom-element.js:790–825

* Ensure that the element is eagerly loaded. * * @param {number=} opt_parentPriority * @return {!Promise} * @final

(opt_parentPriority)

     * @final
     */
    ensureLoaded(opt_parentPriority) {
      return this.mount().then(() => {
        if (this.R1()) {
          if (this.implClass_.usesLoading(this)) {
            this.impl_.ensureLoaded();
          }
          return this.whenLoaded();
        }

        // Very ugly! The "built" signal must be resolved from the Resource
        // and not the element itself because the Resource has not correctly
        // set its state for the downstream to process it correctly.
        const resource = this.getResource_();
        return resource.whenBuilt().then(() => {
          if (resource.getState() == ResourceState_Enum.LAYOUT_COMPLETE) {
            return;
          }
          if (
            resource.getState() != ResourceState_Enum.LAYOUT_SCHEDULED ||
            resource.isMeasureRequested()
          ) {
            resource.measure();
          }
          if (!resource.isDisplayed()) {
            return;
          }
          this.getResources().scheduleLayoutOrPreload(
            resource,
            /* layout */ true,
            opt_parentPriority,
            /* forceOutsideViewport */ true
          );
          return this.whenLoaded();
        });
      });
    }

    /**
     * See `BaseElement.setAsContainer`.