show full screen loader when switching themes

src/app/app.component.html

@@ -1 +1,3 @@
-<ds-themed-root [isNotAuthBlocking]="isNotAuthBlocking$ | async" [isLoading]="isLoading$ | async"></ds-themed-root>
+<ds-themed-root
+  [shouldShowFullscreenLoader]="(isAuthBlocking$ | async) || (isThemeLoading$ | async)"
+  [shouldShowRouteLoader]="isRouteLoading$ | async"></ds-themed-root>

src/app/app.component.ts

@@ -1,4 +1,4 @@
-import { delay, map, distinctUntilChanged, filter, take } from 'rxjs/operators';
+import { delay, distinctUntilChanged, filter, take } from 'rxjs/operators';
 import {
   AfterViewInit,
   ChangeDetectionStrategy,
@@ -7,6 +7,7 @@ import {
   Inject,
   OnInit,
   Optional,
+  PLATFORM_ID,
 } from '@angular/core';
 import { NavigationCancel, NavigationEnd, NavigationStart, Router } from '@angular/router';
 
@@ -32,7 +33,7 @@ import { LocaleService } from './core/locale/locale.service';
 import { hasValue, isNotEmpty } from './shared/empty.util';
 import { KlaroService } from './shared/cookies/klaro.service';
 import { GoogleAnalyticsService } from './statistics/google-analytics.service';
-import { DOCUMENT } from '@angular/common';
+import { DOCUMENT, isPlatformBrowser } from '@angular/common';
 import { ThemeService } from './shared/theme-support/theme.service';
 import { BASE_THEME_NAME } from './shared/theme-support/theme.constants';
 import { DEFAULT_THEME_CONFIG } from './shared/theme-support/theme.effects';
@@ -45,7 +46,6 @@ import { BreadcrumbsService } from './breadcrumbs/breadcrumbs.service';
   changeDetection: ChangeDetectionStrategy.OnPush,
 })
 export class AppComponent implements OnInit, AfterViewInit {
-  isLoading$: BehaviorSubject<boolean> = new BehaviorSubject(true);
   sidebarVisible: Observable<boolean>;
   slideSidebarOver: Observable<boolean>;
   collapsedSidebarWidth: Observable<string>;
@@ -57,11 +57,23 @@ export class AppComponent implements OnInit, AfterViewInit {
   /**
    * Whether or not the authentication is currently blocking the UI
    */
-  isNotAuthBlocking$: Observable<boolean>;
+  isAuthBlocking$: Observable<boolean>;
+
+  /**
+   * Whether or not the app is in the process of rerouting
+   */
+  isRouteLoading$: BehaviorSubject<boolean> = new BehaviorSubject(true);
+
+  /**
+   * Whether or not the theme is in the process of being swapped
+   */
+  isThemeLoading$: BehaviorSubject<boolean> = new BehaviorSubject(false);
+
 
   constructor(
     @Inject(NativeWindowService) private _window: NativeWindowRef,
     @Inject(DOCUMENT) private document: any,
+    @Inject(PLATFORM_ID) private platformId: any,
     private themeService: ThemeService,
     private translate: TranslateService,
     private store: Store<HostWindowState>,
@@ -83,6 +95,10 @@ export class AppComponent implements OnInit, AfterViewInit {
     this.models = models;
 
     this.themeService.getThemeName$().subscribe((themeName: string) => {
+      if (isPlatformBrowser(this.platformId)) {
+        // the theme css will never download server side, so this should only happen on the browser
+        this.isThemeLoading$.next(true);
+      }
       if (hasValue(themeName)) {
         this.setThemeCss(themeName);
       } else if (hasValue(DEFAULT_THEME_CONFIG)) {
@@ -118,13 +134,12 @@ export class AppComponent implements OnInit, AfterViewInit {
   }
 
   ngOnInit() {
-    this.isNotAuthBlocking$ = this.store.pipe(select(isAuthenticationBlocking)).pipe(
+    this.isAuthBlocking$ = this.store.pipe(select(isAuthenticationBlocking)).pipe(
-      map((isBlocking: boolean) => isBlocking === false),
       distinctUntilChanged()
     );
-    this.isNotAuthBlocking$
+    this.isAuthBlocking$
       .pipe(
-        filter((notBlocking: boolean) => notBlocking),
+        filter((isBlocking: boolean) => isBlocking === false),
         take(1)
       ).subscribe(() => this.initializeKlaro());
 
@@ -156,12 +171,12 @@ export class AppComponent implements OnInit, AfterViewInit {
       delay(0)
     ).subscribe((event) => {
       if (event instanceof NavigationStart) {
-        this.isLoading$.next(true);
+        this.isRouteLoading$.next(true);
       } else if (
         event instanceof NavigationEnd ||
         event instanceof NavigationCancel
       ) {
-        this.isLoading$.next(false);
+        this.isRouteLoading$.next(false);
       }
     });
   }
@@ -209,6 +224,8 @@ export class AppComponent implements OnInit, AfterViewInit {
           }
         });
       }
+      // the fact that this callback is used, proves we're on the browser.
+      this.isThemeLoading$.next(false);
     };
     head.appendChild(link);
   }

src/app/root/root.component.html

@@ -1,4 +1,4 @@
-<div class="outer-wrapper" *ngIf="isNotAuthBlocking; else authLoader">
+<div class="outer-wrapper" *ngIf="!shouldShowFullscreenLoader; else fullScreenLoader">
   <ds-admin-sidebar></ds-admin-sidebar>
   <div class="inner-wrapper"  [@slideSidebarPadding]="{
      value: (!(sidebarVisible | async) ? 'hidden' : (slideSidebarOver | async) ? 'shown' : 'expanded'),
@@ -12,10 +12,10 @@
     <main class="main-content">
       <ds-themed-breadcrumbs></ds-themed-breadcrumbs>
 
-      <div class="container d-flex justify-content-center align-items-center h-100" *ngIf="isLoading">
+      <div class="container d-flex justify-content-center align-items-center h-100" *ngIf="shouldShowRouteLoader">
         <ds-loading [showMessage]="false"></ds-loading>
       </div>
-      <div [class.d-none]="isLoading">
+      <div [class.d-none]="shouldShowRouteLoader">
         <router-outlet></router-outlet>
       </div>
     </main>
@@ -23,7 +23,7 @@
     <ds-themed-footer></ds-themed-footer>
   </div>
 </div>
-<ng-template #authLoader>
+<ng-template #fullScreenLoader>
   <div class="ds-full-screen-loader">
     <ds-loading [showMessage]="false"></ds-loading>
   </div>

src/app/root/root.component.spec.ts

@@ -27,6 +27,7 @@ import { provideMockStore } from '@ngrx/store/testing';
 import { RouteService } from '../core/services/route.service';
 import { CUSTOM_ELEMENTS_SCHEMA } from '@angular/core';
 import { MenuServiceStub } from '../shared/testing/menu-service.stub';
+import { NoopAnimationsModule } from '@angular/platform-browser/animations';
 
 describe('RootComponent', () => {
   let component: RootComponent;
@@ -36,6 +37,7 @@ describe('RootComponent', () => {
     await TestBed.configureTestingModule({
       imports: [
         CommonModule,
+        NoopAnimationsModule,
         StoreModule.forRoot(authReducer, storeModuleConfig),
         TranslateModule.forRoot({
           loader: {

src/app/root/root.component.ts

@@ -38,14 +38,14 @@ export class RootComponent implements OnInit {
   models;
 
   /**
-   * Whether or not the authentication is currently blocking the UI
+   * Whether or not to show a full screen loader
    */
-  @Input() isNotAuthBlocking: boolean;
+  @Input() shouldShowFullscreenLoader: boolean;
 
   /**
-   * Whether or not the the application is loading;
+   * Whether or not to show a loader across the router outlet
    */
-  @Input() isLoading: boolean;
+  @Input() shouldShowRouteLoader: boolean;
 
   constructor(
     @Inject(NativeWindowService) private _window: NativeWindowRef,

src/app/root/themed-root.component.ts

@@ -11,14 +11,14 @@ export class ThemedRootComponent extends ThemedComponent<RootComponent> {
   /**
    * Whether or not the authentication is currently blocking the UI
    */
-  @Input() isNotAuthBlocking: boolean;
+  @Input() shouldShowFullscreenLoader: boolean;
 
   /**
    * Whether or not the the application is loading;
    */
-  @Input() isLoading: boolean;
+  @Input() shouldShowRouteLoader: boolean;
 
-  protected inAndOutputNames: (keyof RootComponent & keyof this)[] = ['isLoading', 'isNotAuthBlocking'];
+  protected inAndOutputNames: (keyof RootComponent & keyof this)[] = ['shouldShowRouteLoader', 'shouldShowFullscreenLoader'];
 
   protected getComponentName(): string {
     return 'RootComponent';