forgot to add setttings service

src/app/settings.service.spec.ts

+import { TestBed } from '@angular/core/testing';
+
+import { SettingsService } from './settings.service';
+
+describe('SettingsService', () => {
+  beforeEach(() => TestBed.configureTestingModule({}));
+
+  it('should be created', () => {
+    const service: SettingsService = TestBed.get(SettingsService);
+    expect(service).toBeTruthy();
+  });
+});

src/app/settings.service.ts

+import { Injectable } from '@angular/core';
+import { BehaviorSubject } from 'rxjs';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class SettingsService {
+  public theme$: BehaviorSubject<string>;
+  public menuToggle$: BehaviorSubject<boolean>;
+  public useMenu$: BehaviorSubject<boolean>;
+
+  constructor() { 
+    this.menuToggle$ = new BehaviorSubject<boolean>(true);
+    this.theme$ = new BehaviorSubject<string>('strudel-theme-light');
+    this.useMenu$ = new BehaviorSubject<boolean>(true);
+    this.getTheme();
+  }
+
+  getTheme() {
+    var theme: string;
+    theme = localStorage.getItem('strudel-theme');
+    if (theme == null) {
+      this.theme$.next('strudel-theme-light');
+      return
+    } else {
+      this.theme$.next(theme);
+    }
+  }
+
+  setTheme(v: string) {
+    this.theme$.next(v);
+    localStorage.setItem('strudel-theme',v);
+  }
+}