Function onViewportWrapper

packages/core/src/defer/dom_triggers.ts:43–56

(
  trigger: Element,
  callback: VoidFunction,
  injector: Injector,
  wrapperOptions?: IntersectionObserverInit,
)

 * @param injector Injector that can be used by the trigger to resolve DI tokens.
 */
export function onViewportWrapper(
  trigger: Element,
  callback: VoidFunction,
  injector: Injector,
  wrapperOptions?: IntersectionObserverInit,
) {
  const ngZone = injector.get(NgZone);
  return onViewport(
    trigger,
    () => ngZone.run(callback),
    (options) => ngZone.runOutsideAngular(() => createIntersectionObserver(options)),
    wrapperOptions,
  );
}

/**
 * Helper function to get the LView in which a deferred block's trigger is rendered.