Angular 2 output from router-outlet

Velidan picture Velidan · Jun 6, 2016 · Viewed 52.9k times · Source

I want to make navigation from child components that render inside router-outlet. My parent component have a router config and I want to navigate manually on some event. But I don't know how I can pass from child to parent some data (for navigation) without output. Because this construction is non working

 <router-outlet (navigateTo)="navigateToMessagePart($event)"></router-outlet>

How I can do it in right way? Maybe navigate it from child? But how I can get parent methods from child. Many thanks for any help!

Answer

Antara Datta picture Antara Datta · Feb 1, 2017

<router-outlet></router-outlet> can't be used to emit an event from the child component. One way to communicate between two components is to use a common service.

Create a service

shared-service.ts

import { Observable } from 'rxjs/Observable';
import { Injectable } from '@angular/core';
import { Subject } from 'rxjs/Subject';
@Injectable()
export class SharedService {
    // Observable string sources
    private emitChangeSource = new Subject<any>();
    // Observable string streams
    changeEmitted$ = this.emitChangeSource.asObservable();
    // Service message commands
    emitChange(change: any) {
        this.emitChangeSource.next(change);
    }
}

Now inject the instance of the above service in the constructor of both the parent and child component.

The child component will be emitting a change every time the onClick() method is called

child.component.ts

import { Component} from '@angular/core';
@Component({
    templateUrl: 'child.html',
    styleUrls: ['child.scss']
})
export class ChildComponent {
    constructor(
        private _sharedService: SharedService
    ) { }

onClick(){
  this._sharedService.emitChange('Data from child');

 }
}

The parent component shall receive that change. To do so,capture the subscription inside the parent's constructor.

parent.component.ts

import { Component} from '@angular/core';
@Component({
    templateUrl: 'parent.html',
    styleUrls: ['parent.scss']
})
export class ParentComponent {
    constructor(
        private _sharedService: SharedService
    ) {
          _sharedService.changeEmitted$.subscribe(
        text => {
            console.log(text);
        });
      }

}

Hope this helps :)