12
votes

I've created a "custom" theme, (using the theming documentation at https://material.angular.io/guide/theming, which is pretty bad) like this:

@import '~@angular/material/theming';
@include mat-core();

$ip-primary: mat-palette($mat-indigo);
$ip-accent: mat-palette($mat-pink, A200, A100, A400);
$ip-theme: mat-light-theme($ip-primary, $ip-accent);
$ip-theme-dark: mat-dark-theme($ip-primary, $ip-accent);

.indigo-pink {
  @include angular-material-theme($ip-theme);
}

.indigo-pink-dark {
  @include angular-material-theme($ip-theme-dark);
}

My index.html contains this:

<body class="mat-app-background mat-typography">
  <app-root></app-root>
</body>

In the container for the app-root component, I switch between my custom class names (indigo-pink and indigo-pink-dark) using this:

<div [ngClass]="appTheme">

I am also setting the CDK overlay container class to my custom class name using this:

setContainerClass(className: string): void {
  const containerClassToKeep = 'cdk-overlay-container';
  const overlayClassList = this.overlayContainer.getContainerElement().classList;
  const existingClasses = Array.from(overlayClassList);

  existingClasses.forEach(classToken => {
    if (classToken !== containerClassToKeep) {
      overlayClassList.remove(classToken);
    }
  });

  overlayClassList.add(className);
}

The main problem is that when I switch into the dark theme, I do see the indigo-pink-dark class name get added to my app component container correctly, but only some styles change (e.g. the toolbar at the top goes dark, and Material components) - the body of the page stays white. The theming guide (and other blog posts) say that using the mat-app-background should fix this exact problem.

Additionally though, if I try manually update the background-color of the body, using e.g.

.indigo-pink-dark {
  @include angular-material-theme($ip-theme-dark);

  body & {
    background-color: #000;
  }
}

Then this "background-color" just overlays the entire page and you cannot see any elements on the page. This is something to do with the CDK overlay, because if I remove the part that adds the class name to the overlay, it kind of works - the background of the page does get set correctly, but then overlays do not get correct styling.

5
From what I have faced until now (that is similar to your issue), the best solution I've found is to use a sidenav : the mat-sidenav-content gets its background color from the drak theme. If you don't want to use it, you can also use a material card to apply the color. Simply make a card that is all over the body, and remove the border-radius (and padding if you must). - user4676340
Thanks, yes, I have seen this recommended also, but I want to avoid making the whole site a component if possible :) - danwellman

5 Answers

17
votes

I had the same issue and found this solution on the Angular Material GitHub issue#3298 (post by JamieStill).

I wrapped all of my app.component.html content in a div

<div class="mat-typography app-frame mat-app-background">
    <app-header></app-header>
    <main>
        <app-post-create></app-post-create>
        <app-post-list></app-post-list>
    </main>
</div>

And in app.component.css

html, body, app-root, .app-frame {
    overflow: hidden;
    margin: 0;
    height: 100%;
    box-sizing: border-box;
    color: #e0e0e0;
}

I've only tested this in a practice app in Angular 6, but I suspect it will work in Angular 5 as well.

Before:

Before

After:

After

5
votes

if you add angular material after your project has started, you simply have to manually add mat-app-background class to your body element in your index.html as below:

<body class="mat-typography mat-app-background">
...
</body>
4
votes

Only vh-100 mat-app-background in app.component.html

<div class="vh-100 mat-app-background">
  <router-outlet></router-outlet>
</div>
3
votes

Late in the game, but try to set height to 100%. This is what fixed it for me. Here dark-theme is a global class that has my Angular Material dark theme in it. I put this HTML in app.component.html.

<div class="mat-app-background dark-theme" style="height: 100%;">
  <app-root></app-root>
</div>

This was using Angular 9.

3
votes

I'm not sure why you are you manipulating the CDK overlay container. That seems unnecessary. Just bind your theme classes to the document body. See https://stackblitz.com/edit/angular-ndmju6.

Snippet:

theme: string = 'Light';

constructor(private renderer: Renderer2) {
  this.renderer.addClass(document.body, 'indigo-pink');
}

toggleTheme(): void {

  if (this.theme === 'Light') {
    this.theme = 'Dark';
    this.renderer.addClass(document.body, 'indigo-pink-dark');
    this.renderer.removeClass(document.body, 'indigo-pink');
  } else {
    this.theme = 'Light';
    this.renderer.addClass(document.body, 'indigo-pink');
    this.renderer.removeClass(document.body, 'indigo-pink-dark');
  }
  
}