angular - Open/Close sidenav from another component

Question

I use angular (latest version) and angular material.

There are 3 components:

• header.component, in which there is a control button for right-sidenav
• rigth-sidenav.component, in which is the right-sidenav
• sidenav.component (this is the left main menu), this component calls header.component, right-sidenav.component and content

How to open / close sidenav from another component ? (in my case, the button is in header.component).

Tried the following option (but got the error: TypeError: this.RightSidenavComponent.rightSidenav is undefined):

header.component.html

<button mat-button (click)="toggleRightSidenav()">Toggle side nav</button>

header.component.ts

import { Component } from '@angular/core';
import { RightSidenavComponent } from '../right-sidenav/right-sidenav.component';
@Component({
  selector: 'app-header',
  templateUrl: './header.component.html',
  styleUrls: ['./header.component.scss']
})
export class HeaderComponent {

    constructor(public RightSidenavComponent:RightSidenavComponent) {   }
    toggleRightSidenav() {
        this.RightSidenavComponent.rightSidenav.toggle();
    }

}

sidenav.component.html

<mat-sidenav-container class="sidenav-container">
    <mat-sidenav #sidenav mode="side" opened="true" class="sidenav"
                 [fixedInViewport]="true"> Sidenav  </mat-sidenav>
    <mat-sidenav-content>
        <app-header></app-header>
        <router-outlet></router-outlet>
        <app-right-sidenav #rSidenav></app-right-sidenav>
    </mat-sidenav-content>
</mat-sidenav-container>

sidenav.component.ts

import { Component, Directive, ViewChild } from '@angular/core';
import { RightSidenavComponent } from '../right-sidenav/right-sidenav.component';

@Component({
  selector: 'app-sidenav',
  templateUrl: './sidenav.component.html',
  styleUrls: ['./sidenav.component.scss']
})

export class SidenavComponent {

    @ViewChild('rSidenav') public rSidenav;
    constructor(public RightSidenavComponent: RightSidenavComponent) {
        this.RightSidenavComponent.rightSidenav = this.rSidenav;
    }

}

right-sidenav.component.html

<mat-sidenav #rightSidenav mode="side" opened="true" class="rightSidenav"
             [fixedInViewport]="true" [fixedTopGap]="250">
    Sidenav
</mat-sidenav>

right-sidenav.component.ts

import { Component, Injectable } from '@angular/core';

@Component({
  selector: 'app-right-sidenav',
  templateUrl: './right-sidenav.component.html',
  styleUrls: ['./right-sidenav.component.scss']
})

@Injectable()
export class RightSidenavComponent {

    public rightSidenav: any;

    constructor() { }

}

Non-working sample with code stackblitz

Answer 1

I had the same problem using. I resolved it like this.

SidenavService

import { Injectable } from '@angular/core';
import { MatSidenav } from '@angular/material';

@Injectable()
export class SidenavService {
    private sidenav: MatSidenav;


    public setSidenav(sidenav: MatSidenav) {
        this.sidenav = sidenav;
    }

    public open() {
        return this.sidenav.open();
    }


    public close() {
        return this.sidenav.close();
    }

    public toggle(): void {
    this.sidenav.toggle();
   }

Your Component

constructor(
private sidenav: SidenavService) { }

toggleRightSidenav() {
   this.sidenav.toggle();
}

Bind your html toggle() based on your requirement.

App component.

@ViewChild('sidenav') public sidenav: MatSidenav;

constructor(private sidenavService: SidenavService) {
}

ngAfterViewInit(): void {
  this.sidenavService.setSidenav(this.sidenav);
}

App Module

providers: [YourServices , SidenavService],

Working sample with code stackblitz

Angular 9+ Update

Per this answer on SO, "Components can no longer be imported through @angular/material. Use the individual secondary entry-points, such as @angular/material/button." As such, make sure to import MatSidenav like so:

import { MatSidenav } from '@angular/material/sidenav';