How to call router outlet child component method from parent comonent

Question

I am new to angular2

I have a button in parent component, if

Answer 1

After i searched a lot about this issue, i found a solution and wish it could help you. contentChild/ViewChild have no access to component(and it's data) that is loaded in router-outlet, and using sharedService needs an extra file and more code.

You just need to read component that is loaded in the router outlet:

1. Add template reference to your router outlet:

   <router-outlet #myRouterOutlet ></router-outlet>
   

2. Import the RouterOutlet from @angular/router :

   import {...
      RouterOutlet,
      ..} from "@angular/router";
   

3. And finally, use it:

   @ViewChild("myRouterOutlet", { static: true }) routerOutlet: RouterOutlet;
   buttonClicked(){
       const childComp = this.routerOutlet.component as childComponent;
       childComp.childFunction();
   }
   

Hope it could help you :)

Answer 2

There are basically two ways to display a component's template: As a nested component or as a routing target.

Nested Component

If you use a nested component, then the components are considered to have a "parent component/child component" relationship.

The Html for the parent component would then look like this:

<div>
   <child></child>
</div>

Where "child" is the selector of the child component. You can then communicate between the two using @Input and @Output properties.

For more information on this technique when you have nested components, check out the docs here: https://angular.io/guide/component-interaction

Routing Target

If you use a component as a routing target by displaying it in a <router-outlet>, then there is no "parent component" and "child component" relationship.

The best way to communicate between components in this case is to use a service.

I have a blog post about creating a service here: https://blogs.msmvps.com/deborahk/build-a-simple-angular-service-to-share-data/

Resources

If you are new to Angular, you may save your self a bunch of time and frustration by working through a tutorial or online course. That will introduce all of the basic concepts to get you on your way with Angular quickly.

You can work through the "Tour of Heroes" tutorial here: https://angular.io/tutorial

Or watch a course such as this one: https://app.pluralsight.com/library/courses/angular-2-getting-started-update

Or this one: https://app.pluralsight.com/library/courses/angular-2-first-look/table-of-contents

(You can sign up for a free week.)

Answer 3

Although it is an old questions, all the replies here are not perfect.

By using either service or child instance, you bind yourself to a specific function name that you need to call. service also forces you to use dependency injection.

There is a better way, by using a directive which makes each side completely independent from the other.

the directive is ng-router-outlet-comm.

Answer 4

None of the above solution worked for me in Angular 10. Let me share with you CustomEventHandler service I created to manage this problem:

@Injectable()
export class CustomEventHandler {

    private eventHandlersMap: Map<string, Function> = new Map();

    constructor() {
    }

    public callEvent(eventName: string, data?: any): void {
        this.eventHandlersMap.get(eventName)(data);
    }

    public addListener(eventName: string, callback: Function): void {
        this.eventHandlersMap.set(eventName, callback);
    }
}

You can addListener in child component constructor and call any method in component from parent.

// add listener in child component
this.customEventHandler.addListener("some-event", this.someMethodToCall.bind(this));
// call this in parent component
this.customEventHandler.callEvent("some-event");