Function registerPostOrderHooks

packages/core/src/render3/hooks.ts:97–140

(tView: TView, tNode: TNode)

 * @param tNode The TNode whose directives are to be searched for hooks to queue
 */
export function registerPostOrderHooks(tView: TView, tNode: TNode): void {
  ngDevMode && assertFirstCreatePass(tView);
  // It's necessary to loop through the directives at elementEnd() (rather than processing in
  // directiveCreate) so we can preserve the current hook order. Content, view, and destroy
  // hooks for projected components and directives must be called *before* their hosts.
  for (let i = tNode.directiveStart, end = tNode.directiveEnd; i < end; i++) {
    const directiveDef = tView.data[i] as DirectiveDef<any>;
    ngDevMode && assertDefined(directiveDef, 'Expecting DirectiveDef');
    const lifecycleHooks: AfterContentInit &
      AfterContentChecked &
      AfterViewInit &
      AfterViewChecked &
      OnDestroy = directiveDef.type.prototype;
    const {
      ngAfterContentInit,
      ngAfterContentChecked,
      ngAfterViewInit,
      ngAfterViewChecked,
      ngOnDestroy,
    } = lifecycleHooks;

    if (ngAfterContentInit) {
      (tView.contentHooks ??= []).push(-i, ngAfterContentInit);
    }

    if (ngAfterContentChecked) {
      (tView.contentHooks ??= []).push(i, ngAfterContentChecked);
      (tView.contentCheckHooks ??= []).push(i, ngAfterContentChecked);
    }

    if (ngAfterViewInit) {
      (tView.viewHooks ??= []).push(-i, ngAfterViewInit);
    }

    if (ngAfterViewChecked) {
      (tView.viewHooks ??= []).push(i, ngAfterViewChecked);
      (tView.viewCheckHooks ??= []).push(i, ngAfterViewChecked);
    }

    if (ngOnDestroy != null) {
      (tView.destroyHooks ??= []).push(i, ngOnDestroy);
    }
  }
}

/**
 * Executing hooks requires complex logic as we need to deal with 2 constraints.