Skeleton loader WIP

src/assets/styles/common-utilities.scss

@@ -42,3 +42,23 @@ $sides: (top, bottom, left, right);
         flex: #{$n};
     }
 }
+
+/* SKELETON LINES */
+
+/* sk-w-${n} (in pixels) */
+
+$skeleton-widths: (120, 200, 250, 340);
+@each $w in $skeleton-widths {
+    .sk-w-#{$w} {
+        max-width: #{$w}px;
+    }
+}
+
+/* sk-h-${n} */
+
+$skeleton-heights: (12, 20, 24);
+@each $h in $skeleton-heights {
+    .sk-h-#{$h} {
+        height: #{$h}px;
+    }
+}

src/lib/common-ui.module.ts

@@ -5,7 +5,7 @@ import { TranslateModule } from '@ngx-translate/core';
 import { MatLegacyProgressSpinnerModule as MatProgressSpinnerModule } from '@angular/material/legacy-progress-spinner';
 import { SortByPipe } from './sorting';
 import { CommonUiOptions, IqserAppConfig, ModuleWithOptions } from './utils';
-import { HiddenActionComponent, LogoComponent, ToastComponent } from './shared';
+import { HiddenActionComponent, ToastComponent } from './shared';
 import { ConnectionStatusComponent, FullPageErrorComponent } from './error';
 import { IqserListingModule } from './listing';
 import { IqserFiltersModule } from './filtering';
@@ -24,6 +24,7 @@ import { MatLegacyTooltipModule as MatTooltipModule } from '@angular/material/le
 import { ApiPathInterceptor, IqserConfigService, IqserUserPreferenceService } from './services';
 import { DefaultUserPreferenceService } from './services/default-user-preference.service';
 import { HTTP_INTERCEPTORS, HttpClientModule } from '@angular/common/http';
+import { IqserSkeletonModule } from './skeleton/skeleton.module';
 
 const matModules = [
     MatIconModule,
@@ -42,16 +43,10 @@ const modules = [
     IqserInputsModule,
     IqserScrollbarModule,
     IqserEmptyStatesModule,
+    IqserSkeletonModule,
     HttpClientModule,
 ];
-const components = [
-    ConnectionStatusComponent,
-    FullPageErrorComponent,
-    LogoComponent,
-    HiddenActionComponent,
-    ConfirmationDialogComponent,
-    ToastComponent,
-];
+const components = [ConnectionStatusComponent, FullPageErrorComponent, HiddenActionComponent, ConfirmationDialogComponent, ToastComponent];
 
 const pipes = [SortByPipe];
 

src/lib/services/composite-route.guard.ts

@@ -2,15 +2,20 @@ import { ActivatedRouteSnapshot, CanActivate, RouterStateSnapshot, UrlTree } fro
 import { Injectable, InjectionToken, Injector } from '@angular/core';
 import { firstValueFrom, from, of } from 'rxjs';
 import { LoadingService } from '../loading';
+import { SkeletonService } from './skeleton.service';
 
 @Injectable({
     providedIn: 'root',
 })
 export class CompositeRouteGuard implements CanActivate {
-    constructor(protected readonly _injector: Injector, private readonly _loadingService: LoadingService) {}
+    constructor(
+        protected readonly _injector: Injector,
+        private readonly _loadingService: LoadingService,
+        private readonly _skeletonService: SkeletonService,
+    ) {}
 
     async canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Promise<boolean> {
-        this._loadingService.start();
+        this.#preChecks(route);
 
         const routeGuards = <InjectionToken<CanActivate>[]>route.data['routeGuards'];
 
@@ -27,14 +32,30 @@ export class CompositeRouteGuard implements CanActivate {
 
                 const result = await firstValueFrom(canActivateResult);
                 if (!result) {
-                    this._loadingService.stop();
+                    this.#postChecks(route);
                     return false;
                 }
             }
         }
 
-        this._loadingService.stop();
-
+        this.#postChecks(route);
         return true;
     }
+
+    #preChecks(route: ActivatedRouteSnapshot): void {
+        const skeleton = route.data['skeleton'];
+        if (skeleton) {
+            this._skeletonService.setType(skeleton);
+        } else {
+            this._loadingService.start();
+        }
+    }
+
+    #postChecks(route: ActivatedRouteSnapshot): void {
+        if (route.data['skeleton']) {
+            this._skeletonService.clear();
+        } else {
+            this._loadingService.stop();
+        }
+    }
 }

src/lib/services/index.ts

@@ -9,3 +9,4 @@ export * from './iqser-user-preference.service';
 export * from './language.service';
 export * from './iqser-config.service';
 export * from './api-path.interceptor';
+export * from './skeleton.service';

src/lib/services/skeleton.service.ts

@@ -0,0 +1,17 @@
+import { Injectable } from '@angular/core';
+import { BehaviorSubject } from 'rxjs';
+
+@Injectable({
+    providedIn: 'root',
+})
+export class SkeletonService {
+    type$ = new BehaviorSubject<string | null>(null);
+
+    clear() {
+        this.type$.next(null);
+    }
+
+    setType(type: string) {
+        this.type$.next(type);
+    }
+}

src/lib/shared/shared.module.ts

@@ -1,13 +1,14 @@
 import { NgModule } from '@angular/core';
-import { SideNavComponent, SmallChipComponent, StatusBarComponent } from './index';
+import { LogoComponent, SideNavComponent, SmallChipComponent, StatusBarComponent } from './index';
 import { CommonModule } from '@angular/common';
 import { MatLegacyTooltipModule as MatTooltipModule } from '@angular/material/legacy-tooltip';
+import { IqserIconsModule } from '../icons';
 
-const components = [SmallChipComponent, StatusBarComponent, SideNavComponent];
+const components = [SmallChipComponent, StatusBarComponent, SideNavComponent, LogoComponent];
 
 @NgModule({
     declarations: [...components],
     exports: [...components],
-    imports: [CommonModule, MatTooltipModule],
+    imports: [CommonModule, MatTooltipModule, IqserIconsModule],
 })
 export class IqserSharedModule {}

src/lib/skeleton/skeleton.module.ts

@@ -0,0 +1,12 @@
+import { NgModule } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { SkeletonComponent } from './skeleton/skeleton.component';
+import { IqserSharedModule } from '../shared';
+import { IqserUsersModule } from '../users';
+
+@NgModule({
+    declarations: [SkeletonComponent],
+    exports: [SkeletonComponent],
+    imports: [CommonModule, IqserSharedModule, IqserUsersModule],
+})
+export class IqserSkeletonModule {}

src/lib/skeleton/skeleton/skeleton.component.html

@@ -0,0 +1,3 @@
+<ng-container *ngIf="type$ | async as type">
+    <ng-container *ngTemplateOutlet="templates[type]"></ng-container>
+</ng-container>

src/lib/skeleton/skeleton/skeleton.component.scss

@@ -0,0 +1,5 @@
+:host {
+    position: absolute;
+    width: 100vw;
+    z-index: 2;
+}

src/lib/skeleton/skeleton/skeleton.component.ts

@@ -0,0 +1,29 @@
+import { ChangeDetectionStrategy, Component, HostBinding, Input, TemplateRef } from '@angular/core';
+import { BehaviorSubject } from 'rxjs';
+import { SkeletonService } from '../../services';
+
+@Component({
+    selector: 'iqser-skeleton [templates]',
+    templateUrl: './skeleton.component.html',
+    styleUrls: ['./skeleton.component.scss'],
+    changeDetection: ChangeDetectionStrategy.OnPush,
+})
+export class SkeletonComponent {
+    x$ = new BehaviorSubject<string | null>('Dashboard');
+    @HostBinding('style.display') display = 'block';
+
+    @Input() templates: Record<string, TemplateRef<unknown>> = {};
+
+    // @HostBinding('style.display') display = 'none';
+
+    constructor(private readonly _skeletonService: SkeletonService) {
+        // this._skeletonService.type$.subscribe(type => {
+        //     this.display = type ? 'block' : 'none';
+        // });
+    }
+
+    get type$(): BehaviorSubject<string | null> {
+        return this.x$;
+        // return this._skeletonService.type$;
+    }
+}