Angular 10 References/ Core
References
Oleksa Novyk | GitHub

@ContentChildren

You can use ContentChildren to get the QueryList of elements or directives from the content DOM. Any time a child element is added, removed, or moved, the query list will be updated, and the changes observable of the query list will emit a new value.

Content queries are set before the ngAfterContentInit callback is called.

Example

Here is a simple demonstration of how the ContentChildren decorator can be used.

import {AfterContentInit, ContentChildren, Directive, QueryList} from '@angular/core';

@Directive({selector: 'child-directive'})
class ChildDirective {
}

@Directive({selector: 'someDir'})
class SomeDir implements AfterContentInit {
  @ContentChildren(ChildDirective) contentChildren: QueryList<ChildDirective>;

  ngAfterContentInit() {
    // contentChildren is set
  }
}
Links & Tutorials

Options

@ContentChildren(
  selector: Type<any>|Function|string, 
  opts?: {descendants?: boolean, read?: any},
)

selector#

selector: Type<any>|Function|string
The directive type or the name used for querying.Supported selectors include: * any class with the `@Component` or `@Directive` decorator * a template reference variable as a string (e.g. query `` with `@ViewChild('cmp')`) * any provider defined in the child component tree of the current component (e.g. `@ViewChild(SomeService) someService: SomeService`) * any provider defined through a string token (e.g. `@ViewChild('someToken') someTokenVal: any`) * a `TemplateRef` (e.g. query `` with `@ViewChild(TemplateRef) template;`)

opts#

opts?: {descendants?: boolean, read?: any}
Additional options. * `descendants` - include only direct children or all descendants. * `read` - read a different token from the queried elements.