Angular Material 2. Switch theme from light to dark on click

Question

So I have an Angular 2 Material application. And all I wanna do is just switch/toggle theme from dark to light by clicking simple button.

How can I do it ?

Answer 1

You can conditionally apply a CSS class to the document using the class binding syntax. This CSS class can then hold styling information for the application's dark theme.

In your menu:

app.component.html:

<div [class.dark-theme]="isDarkTheme">
    <!--Your application content here-->
    <mat-menu #more="mdMenu">
        <!--Your content here-->
        <button mat-menu-item (click)="changeTheme()">
            Change Theme
        </button>
    </mat-menu>
</div>

app.component.ts:

// import statements here
import {Component} from '@angular/core';

export class AppComponent {
    // Initialize isDarkTheme to false
    isDarkTheme: boolean = false;
    // Your code here
    
    changeTheme(): void {
        if (this.isDarkTheme) {
           this.isDarkTheme = false;
        } else {
           this.isDarkTheme = true;
        }
     }
}

You can then have the class specify the dark theme variant in your SCSS configuration:

theme.scss:

@import '~@angular/material/core/theming/_all-theme';

@include mat-core();
.dark-theme {
    // Dark theme
    $app-dark-primary: mat-palette($mat-pink, 700);
    $app-dark-accent: mat-palette($mat-blue-grey);
    $app-dark-theme: mat-dark-theme($app-dark-primary, $app-dark-accent);

    @include angular-material-theme($app-dark-theme);
}