feat(docs-infra): change navigation in resources page (#34756)

https://angular.io/resources needs to be sturctured to be able to navigate to all resources with improved user experience. A lone scroll bar in this page will not help the reader a great deal in exploring the resources

Fixes #33526

PR Close #34756

aio/src/app/custom-elements/resource/resource-list.component.html

@@ -1,13 +1,14 @@
 <div class="resources-container">
-    <div class="l-flex--column">
-      <div class="showcase" *ngFor="let category of categories">
-        <header class="c-resource-header">
-          <a class="h-anchor-offset" id="{{category.id}}"></a>
-          <h2>{{category.title}}</h2>
-        </header>
-
-        <div class="shadow-1">
-          <div *ngFor="let subCategory of category.subCategories">
+  <div class="flex-center group-buttons">
+    <a *ngFor="let category of categories"
+      [class.selected]="category.id == selectedCategory.id"
+      class="button mat-button filter-button"
+      (click)="selectCategory(category.id)"
+      (keyup.enter)="selectCategory(category.id)">{{category.title}}</a>
+  </div>
+  <div class="l-flex--column align-items-center">
+    <div class="shadow-1 showcase">
+      <div *ngFor="let subCategory of selectedCategory?.subCategories">
         <a class="h-anchor-offset" id="{{subCategory.id}}"></a>
         <h3 class="subcategory-title">{{subCategory.title}}</h3>
 
@@ -25,4 +26,3 @@
     </div>
   </div>
 </div>
-</div>

aio/src/app/custom-elements/resource/resource-list.component.spec.ts

@@ -1,78 +1,115 @@
 import { ReflectiveInjector } from '@angular/core';
-import { PlatformLocation } from '@angular/common';
 
 import { of } from 'rxjs';
 
 import { ResourceListComponent } from './resource-list.component';
 import { ResourceService } from './resource.service';
-
+import { LocationService } from 'app/shared/location.service';
 import { Category } from './resource.model';
 
 // Testing the component class behaviors, independent of its template
 // Let e2e tests verify how it displays.
 describe('ResourceListComponent', () => {
 
+  let component: ResourceListComponent;
   let injector: ReflectiveInjector;
-  let location: TestPlatformLocation;
+  let resourceService: TestResourceService;
+  let locationService: TestLocationService;
+  let categories: Category[];
 
   beforeEach(() => {
     injector = ReflectiveInjector.resolveAndCreate([
       ResourceListComponent,
-      {provide: PlatformLocation, useClass: TestPlatformLocation },
-      {provide: ResourceService, useClass: TestResourceService }
+      {provide: ResourceService, useClass: TestResourceService },
+      {provide: LocationService, useClass: TestLocationService }
     ]);
 
-    location = injector.get(PlatformLocation);
+    locationService = injector.get(LocationService);
+    resourceService = injector.get(ResourceService);
+    categories = resourceService.testCategories;
   });
 
-  it('should set the location w/o leading slashes', () => {
-    location.pathname = '////resources';
-    const component = getComponent();
-    expect(component.location).toBe('resources');
+  it('should select the first category when no query string', () => {
+    component = getComponent();
+    expect(component.selectedCategory).toBe(categories[0]);
   });
 
-  it('href(id) should return the expected href', () => {
-    location.pathname = '////resources';
-    const component = getComponent();
-    expect(component.href({id: 'foo'})).toBe('resources#foo');
+  it('should select the first category when query string w/o "category" property', () => {
+    locationService.searchResult = { foo: 'development' };
+    component = getComponent();
+    expect(component.selectedCategory).toBe(categories[0]);
   });
 
-  it('should set scroll position to zero when no target element', () => {
-    const component = getComponent();
-    component.onScroll(undefined);
-    expect(component.scrollPos).toBe(0);
+  it('should select the first category when query category not found', () => {
+    locationService.searchResult = { category: 'foo' };
+    component = getComponent();
+    expect(component.selectedCategory).toBe(categories[0]);
   });
 
-  it('should set scroll position to element.scrollTop when that is defined', () => {
-    const component = getComponent();
-    component.onScroll({scrollTop: 42});
-    expect(component.scrollPos).toBe(42);
+  it('should select the education category when query category is "education"', () => {
+    locationService.searchResult = { category: 'education' };
+    component = getComponent();
+    expect(component.selectedCategory).toBe(categories[1]);
   });
 
-  it('should set scroll position to element.body.scrollTop when that is defined', () => {
-    const component = getComponent();
-    component.onScroll({body: {scrollTop: 42}});
-    expect(component.scrollPos).toBe(42);
+  it('should select the education category when query category is "EDUCATION" (case insensitive)', () => {
+    locationService.searchResult = { category: 'EDUCATION' };
+    component = getComponent();
+    expect(component.selectedCategory).toBe(categories[1]);
   });
 
-  it('should set scroll position to 0 when no target.body.scrollTop defined', () => {
-    const component = getComponent();
-    component.onScroll({body: {}});
-    expect(component.scrollPos).toBe(0);
+  it('should set the query to the "education" category when user selects "education"', () => {
+    component = getComponent();
+    component.selectCategory('education');
+    expect(locationService.searchResult['category']).toBe('education');
+  });
+
+  it('should set the query to the first category when user selects unknown name', () => {
+    component = getComponent();
+    component.selectCategory('education'); // a legit group that isn't the first
+
+    component.selectCategory('foo'); // not a legit group name
+    expect(locationService.searchResult['category']).toBe('development');
   });
 
   //// Test Helpers ////
-  function  getComponent(): ResourceListComponent { return injector.get(ResourceListComponent); }
-
-  class TestPlatformLocation {
-    pathname = 'resources';
+  function  getComponent(): ResourceListComponent {
+    const comp = injector.get(ResourceListComponent);
+    comp.ngOnInit();
+    return comp;
   }
 
   class TestResourceService {
-    categories = of(getTestData);
+    testCategories = getTestData();
+    categories = of(this.testCategories);
+  }
+
+  interface SearchResult { [index: string]: string; }
+
+  class TestLocationService {
+    searchResult: SearchResult = {};
+    search = jasmine.createSpy('search').and.callFake(() => this.searchResult);
+    setSearch = jasmine.createSpy('setSearch')
+      .and.callFake((_label: string, result: SearchResult) => {
+        this.searchResult = result;
+      });
   }
 
   function getTestData(): Category[] {
-    return []; // Not interested in the data in these tests
+    return [
+      // Not interested in the sub-categories data in these tests
+      {
+        id: 'development',
+        title: 'Development',
+        order: 0,
+        subCategories: []
+      },
+      {
+        id: 'education',
+        title: 'Education',
+        order: 1,
+        subCategories: []
+      },
+    ];
   }
 });

aio/src/app/custom-elements/resource/resource-list.component.ts

@@ -2,6 +2,7 @@ import { Component, OnInit } from '@angular/core';
 
 import { Category } from './resource.model';
 import { ResourceService } from './resource.service';
+import { LocationService } from 'app/shared/location.service';
 
 /* tslint:disable:template-accessibility-elements-content */
 @Component({
@@ -11,16 +12,27 @@ import { ResourceService } from './resource.service';
 export class ResourceListComponent implements OnInit {
 
   categories: Category[];
-  location: string;
+  selectedCategory: Category;
 
   constructor(
-    private resourceService: ResourceService) {
-    this.location = location.pathname.replace(/^\/+/, '');
+    private resourceService: ResourceService,
+    private locationService: LocationService) {
   }
 
   ngOnInit() {
+    const category =  this.locationService.search()['category'] || '';
     // Not using async pipe because cats appear twice in template
     // No need to unsubscribe because categories observable completes.
-    this.resourceService.categories.subscribe(cats => this.categories = cats);
+    this.resourceService.categories.subscribe(cats => {
+      this.categories = cats;
+      this.selectCategory(category);
+    });
+  }
+
+  selectCategory(id: string) {
+    id = id.toLowerCase();
+    this.selectedCategory =
+      this.categories.find(category => category.id.toLowerCase() === id) || this.categories[0];
+    this.locationService.setSearch('', {category: this.selectedCategory.id});
   }
 }

aio/src/styles/2-modules/_resources.scss

@@ -169,6 +169,10 @@ aio-resource-list {
     flex-direction: column;
   }
 
+  .align-items-center{
+    align-items: center;
+  }
+
   .c-resource-header {
     margin-bottom: 16px;
   }