Closing Secondary Router-Outlet Views From Within The Named-Route View Components In Angular 4.4.4

// Import the core angular services.
import { BrowserModule } from "@angular/platform-browser";
import { NgModule } from "@angular/core";
import { RouterModule } from "@angular/router";
import { Routes } from "@angular/router";

// Import the application components and services.
import { AppComponent } from "./app.component";
import { ChatComponent } from "./chat.component";
import { LayoutAComponent } from "./layout-a.component";
import { LayoutBComponent } from "./layout-b.component";
import { LayoutWrapperComponent } from "./layout-wrapper.component";

// ----------------------------------------------------------------------------------- //
// ----------------------------------------------------------------------------------- //

var routes: Routes = [
	{
		// CAUTION: In order for the NAMED OUTLET child route to work (chat),
		// its parent segment must contain a non-empty path. As such, we're
		// using "main" for this wrapper component in order to ensure a non-
		// empty path segment.
		path: "main",
		component: LayoutWrapperComponent,
		children: [
			{
				path: "layout-a",
				component: LayoutAComponent
			},
			{
				path: "layout-b",
				component: LayoutBComponent
			},
			{
				outlet: "chat", // <--- Named outlet.
				path: "open",
				component: ChatComponent
			}
		]
	}

	// NOTE: We are OMITTING any not-found / catch-all REDIRECT as including it will
	// partially mask the fact that some of our code is broken. Essentially, the redirect
	// hides the broken URLs that get created.
	// {
	// path: "**",
	// redirectTo: "/main/layout-a"
	// }
];

// ----------------------------------------------------------------------------------- //
// ----------------------------------------------------------------------------------- //

@NgModule({
	bootstrap: [
		AppComponent
	],
	imports: [
		BrowserModule,
		RouterModule.forRoot(
			routes,
			{
				// Tell the router to use the HashLocationStrategy.
				useHash: true
			}
		)
	],
	declarations: [
		AppComponent,
		ChatComponent,
		LayoutAComponent,
		LayoutBComponent,
		LayoutWrapperComponent
	],
	providers: [
		// CAUTION: We don't need to specify the LocationStrategy because we are setting
		// the "useHash" property in the Router module above.
		// --
		// {
		// provide: LocationStrategy,
		// useClass: HashLocationStrategy
		// }
	]
})
export class AppModule {
	// ...
}

// Import the core angular services.
import { ActivatedRoute } from "@angular/router";
import { Component } from "@angular/core";
import { Router } from "@angular/router";

// ----------------------------------------------------------------------------------- //
// ----------------------------------------------------------------------------------- //

@Component({
	selector: "chat",
	styleUrls: [ "./chat.component.css" ],
	template:
	`
		<h3>
			Chat Widget
		</h3>

		<p>
			<em>How can I help you?</em>
		</p>

		<h4>
			Self-Closing Functionality
		</h4>

		<p>
			<a [routerLink]="[ '../', { outlets: { chat: null } } ]">Close (via RouterLink)</a>
			&mdash;
			<strong>Broken</strong>
			<em>(will appear to work, but will break on page-refresh)</em>.
		</p>

		<p>
			<a (click)="closeChatViaMe()">Close (via .navigate() using self)</a>
			&mdash;
			<strong>Broken</strong>
			<em>(will appear to work, but will break on page-refresh)</em>.
		</p>

		<p>
			<a (click)="closeChatViaParent()">Close (via .navigate() using parent)</a>
		</p>
	`
})
export class ChatComponent {

	private activatedRoute: ActivatedRoute;
	private router: Router;

	// I initialize the chat view component.
	constructor( activatedRoute: ActivatedRoute, router: Router ) {

		this.activatedRoute = activatedRoute;
		this.router = router;

	}

	// ---
	// PUBLIC METHODS.
	// ---

	// I attempt to close the chat by nullifying the secondary outlet using RELATIVE PATH
	// navigation commands.
	// --
	// CAUTION: This is BROKEN. This DOES NOT WORK.
	public closeChatViaMe() : void {

		this.router.navigate(
			[
				"../",
				{
					outlets: {
						chat: null
					}
				}
			],
			{
				relativeTo: this.activatedRoute
			}
		);

	}


	// I attempt to close the chat by nullifying the secondary outlet using the PARENT'S
	// ACTIVATED ROUTE.
	public closeChatViaParent() : void {

		this.router.navigate(
			[
				// NOTE: No relative-path navigation is required because we are accessing
				// the parent's "activatedRoute" instance. As such, this will be executed
				// as if we were doing this in the parent view component.
				{
					outlets: {
						chat: null
					}
				}
			],
			{
				relativeTo: this.activatedRoute.parent // <--- PARENT activated route.
			}
		);

	}

}

[routerLink]="[ '../', { outlets: { chat: null } } ]

this.router.navigate(
	[
		"../",
		{
			outlets: {
				chat: null
			}
		}
	],
	{
		relativeTo: this.activatedRoute
	}
);

this.router.navigate(
	[
		{
			outlets: {
				chat: null
			}
		}
	],
	{
		relativeTo: this.activatedRoute.parent // <--- PARENT activated route.
	}
);