My Biggest Angular Mistakes and How To Avoid Them

Every developer makes mistakes, even with years of experience. But these mistakes are a great opportunity to learn something new and gain valuable lessons. In this talk, Fabian Gosebrink shares the mistakes he has made while developing with Angular and how to avoid them. Using real-world projects as examples, he highlights common pitfalls that can affect both beginners and experienced developers alike. These include architectural challenges, inefficient state management strategies, and unexpected performance issues. By the end of this talk, participants will gain insights on how to make their projects more future-proof and stable.

1. My biggest Angular mistakes And how to Avoid Them
2. I was a Dumb Developer
3. I Still am a Dumb Developer
4. I know a little bit more now
5. My biggest Angular mistakes
6. My biggest Angular mistakes And how to Avoid Them
7. fabiangosebrink.bsky.social Fabian Gosebrink
8. Lessons from a developer’s journey
9. Opinionated
10. Components
11. Components Relationship of
12. Components Container
13. Components Presentational
14. <section class="vh-100"> <div class="container py-5 h-100"> <div class="row d-flex justify-content-center align-items-center h-100"> <div class="col col-xl-10"> <div class="card" style="border-radius: 15px"> <div class="card-body p-5"> <h6 class="mb-3"> Awesome Todo List ({{ store.doneCount() }}/{{ store.undoneCount() }} {{ store.percentageDone() | number : "1.0-0" }}% done) </h6> <form (ngSubmit)="addTodo()" class="d-flex justify-content-center align-items-center mb-4" [formGroup]="form" > <div class="form-outline flex-fill"> <input formControlName="todoValue" type="text" id="form1" class="form-control form-control-lg" /> </div> <button type="submit" [disabled]="form.invalid" class="btn btn-primary btn-lg ms-2" > Add </button> </form> <ul class="list-group mb-0"> @for (item of store.items(); track item.id) { <li class="list-group-item d-flex" > <div class="d-flex align-items-center"> <input class="form-check-input me-2" type="checkbox" [checked]="item.done" value="" aria-label="..." (click)="store.toggleDone(item)" /> {{ item.value }} </div> <button type="button" class="btn btn-danger btn-sm" (click)="store.deleteItem(item)" > Delete </button> </li> } </ul> </div> </div> </div> </div> </div> </section> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
15. <section class="vh-100"> <div class="container py-5 h-100"> <div class="row d-flex justify-content-center align-items-center h-100"> <div class="col col-xl-10"> <div class="card" style="border-radius: 15px"> <div class="card-body p-5"> <h6 class="mb-3"> Awesome Todo List ({{ store.doneCount() }}/{{ store.undoneCount() }} {{ store.percentageDone() | number : "1.0-0" }}% done) </h6> <form (ngSubmit)="addTodo()" class="d-flex justify-content-center align-items-center mb-4" [formGroup]="form" > <div class="form-outline flex-fill"> <input formControlName="todoValue" type="text" id="form1" class="form-control form-control-lg" /> </div> <button type="submit" [disabled]="form.invalid" class="btn btn-primary btn-lg ms-2" > Add </button> </form> <ul class="list-group mb-0"> @for (item of store.items(); track item.id) { <li class="list-group-item d-flex" > <div class="d-flex align-items-center"> <input class="form-check-input me-2" type="checkbox" [checked]="item.done" value="" aria-label="..." (click)="store.toggleDone(item)" /> {{ item.value }} </div> <button type="button" class="btn btn-danger btn-sm" (click)="store.deleteItem(item)" > Delete </button> </li> } </ul> </div> </div> </div> </div> </div> </section> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 That's a lot! Doing multiple Things
16. <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Separation Container Presentational
17. <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <div class="..."> 1 2 3 4 5 6 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 Separation Container Presentational
18. <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <div class="..."> 1 2 3 4 5 6 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 <app-todo-form (todoAdded)="addTodo($event)" /> <div class="..."> 1 2 <app-todo-header 3 [count]="count()" 4 [doneItems]="doneItems()" 5 [openItems]="openItems()" 6 /> 7 8 9 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 Separation Container Presentational
19. <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <div class="..."> 1 2 3 4 5 6 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 <app-todo-form (todoAdded)="addTodo($event)" /> <div class="..."> 1 2 <app-todo-header 3 [count]="count()" 4 [doneItems]="doneItems()" 5 [openItems]="openItems()" 6 /> 7 8 9 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> <div class="..."> 1 2 <app-todo-header 3 [count]="count()" 4 [doneItems]="doneItems()" 5 [openItems]="openItems()" 6 /> 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 12 13 14 15 16 17 </div> 18 Separation Container Presentational
20. <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <div class="..."> 1 2 3 4 5 6 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 <app-todo-form (todoAdded)="addTodo($event)" /> <div class="..."> 1 2 <app-todo-header 3 [count]="count()" 4 [doneItems]="doneItems()" 5 [openItems]="openItems()" 6 /> 7 8 9 10 11 <app-todo-list 12 [items]="sortedTodos()" 13 (delete)="deleteTodo($event)" 14 (markAsDone)="markAsDone($event)" 15 /> 16 17 </div> 18 <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> <div class="..."> 1 2 <app-todo-header 3 [count]="count()" 4 [doneItems]="doneItems()" 5 [openItems]="openItems()" 6 /> 7 8 <app-todo-form 9 (todoAdded)="addTodo($event)" /> 10 11 12 13 14 15 16 17 </div> 18 <div class="..."> <app-todo-header [count]="count()" [doneItems]="doneItems()" [openItems]="openItems()" /> <app-todo-form (todoAdded)="addTodo($event)" /> <app-todo-list [items]="sortedTodos()" (delete)="deleteTodo($event)" (markAsDone)="markAsDone($event)" /> </div> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Separation Container Presentational
21. Container Presentational Presentational
22. Main Form List
23. Where HOw HOw
24. state "no" state "No" state
26. Easier to test
27. Easier to test @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
28. Easier to test @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) 1 2 3 4 5 6 export class DoggoListComponent { 7 doggos = input([]); 8 9 doggoSelected = output<string>(); 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15
29. Easier to test @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) 1 2 3 4 5 6 export class DoggoListComponent { 7 doggos = input([]); 8 9 doggoSelected = output<string>(); 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15 export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 7 8 9 10 11 12 13 14 15
30. Easier to test @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) 1 2 3 4 5 6 export class DoggoListComponent { 7 doggos = input([]); 8 9 doggoSelected = output<string>(); 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15 export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 7 8 9 10 11 12 13 14 15 doggos = input([]); doggoSelected = output<string>(); @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 export class DoggoListComponent { 7 8 9 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15
31. Easier to test @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 @Component({ selector: 'app-doggo-list', templateUrl: './doggo-list.component.html', styleUrls: ['./doggo-list.component.scss'], changeDetection: ChangeDetectionStrategy.OnPush, }) 1 2 3 4 5 6 export class DoggoListComponent { 7 doggos = input([]); 8 9 doggoSelected = output<string>(); 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15 export class DoggoListComponent { doggos = input([]); doggoSelected = output<string>(); selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } } @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 7 8 9 10 11 12 13 14 15 doggos = input([]); doggoSelected = output<string>(); @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 export class DoggoListComponent { 7 8 9 10 11 selectDoggo(doggo: Doggo): void { 12 this.doggoSelected.emit(doggo.id); 13 } 14 } 15 selectDoggo(doggo: Doggo): void { this.doggoSelected.emit(doggo.id); } @Component({ 1 selector: 'app-doggo-list', 2 templateUrl: './doggo-list.component.html', 3 styleUrls: ['./doggo-list.component.scss'], 4 changeDetection: ChangeDetectionStrategy.OnPush, 5 }) 6 export class DoggoListComponent { 7 doggos = input([]); 8 9 doggoSelected = output<string>(); 10 11 12 13 14 } 15
32. Easier to test describe('DoggoListComponent', () => { let component: DoggoListComponent; let fixture: ComponentFixture<DoggoListComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); fixture = TestBed.createComponent(DoggoListComponent); component = fixture.componentInstance; fixture.detectChanges(); }); it('should create', () => { expect(component).toBeTruthy(); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
33. Easier to test describe('DoggoListComponent', () => { let component: DoggoListComponent; let fixture: ComponentFixture<DoggoListComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); fixture = TestBed.createComponent(DoggoListComponent); component = fixture.componentInstance; fixture.detectChanges(); }); it('should create', () => { expect(component).toBeTruthy(); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); describe('DoggoListComponent', () => { 1 let component: DoggoListComponent; 2 let fixture: ComponentFixture<DoggoListComponent>; 3 4 5 6 7 8 9 fixture = TestBed.createComponent(DoggoListComponent); 10 component = fixture.componentInstance; 11 fixture.detectChanges(); 12 }); 13 14 it('should create', () => { 15 expect(component).toBeTruthy(); 16 }); 17 18
34. Easier to test describe('DoggoListComponent', () => { let component: DoggoListComponent; let fixture: ComponentFixture<DoggoListComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); fixture = TestBed.createComponent(DoggoListComponent); component = fixture.componentInstance; fixture.detectChanges(); }); it('should create', () => { expect(component).toBeTruthy(); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); describe('DoggoListComponent', () => { 1 let component: DoggoListComponent; 2 let fixture: ComponentFixture<DoggoListComponent>; 3 4 5 6 7 8 9 fixture = TestBed.createComponent(DoggoListComponent); 10 component = fixture.componentInstance; 11 fixture.detectChanges(); 12 }); 13 14 it('should create', () => { 15 expect(component).toBeTruthy(); 16 }); 17 18 it('should emit event when method is called', () => { // arrange const spy = jest.spyOn(component.doggoSelected, 'emit'); // act component.selectDoggo({ id: 'my-id' } as Doggo); // assert expect(spy).toHaveBeenCalled(); }); fixture.detectChanges(); 12 }); 13 14 it('should create', () => { 15 expect(component).toBeTruthy(); 16 }); 17 18 19 20 21 22 23 24 25 26 27 28 }) 29
35. Easier to test describe('DoggoListComponent', () => { let component: DoggoListComponent; let fixture: ComponentFixture<DoggoListComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); fixture = TestBed.createComponent(DoggoListComponent); component = fixture.componentInstance; fixture.detectChanges(); }); it('should create', () => { expect(component).toBeTruthy(); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); describe('DoggoListComponent', () => { 1 let component: DoggoListComponent; 2 let fixture: ComponentFixture<DoggoListComponent>; 3 4 5 6 7 8 9 fixture = TestBed.createComponent(DoggoListComponent); 10 component = fixture.componentInstance; 11 fixture.detectChanges(); 12 }); 13 14 it('should create', () => { 15 expect(component).toBeTruthy(); 16 }); 17 18 describe('DoggoListComponent', () => { 1 let component: DoggoListComponent; 2 let fixture: ComponentFixture<DoggoListComponent>; 3 4 beforeEach(async () => { 5 await TestBed.configureTestingModule({ 6 imports: [DoggoListComponent], 7 }).compileComponents(); 8 9 fixture = TestBed.createComponent(DoggoListComponent); 10 component = fixture.componentInstance; 11 fixture.detectChanges(); 12 }); 13 14 it('should create', () => { 15 expect(component).toBeTruthy(); 16 }); 17 18 describe('DoggoListComponent', () => { let component: DoggoListComponent; let fixture: ComponentFixture<DoggoListComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [DoggoListComponent], }).compileComponents(); fixture = TestBed.createComponent(DoggoListComponent); component = fixture.componentInstance; fixture.detectChanges(); }); it('should create', () => { expect(component).toBeTruthy(); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
36. Easier to test @Component({ selector: 'app-main-doggo', templateUrl: './main-doggo.component.html', styleUrls: ['./main-doggo.component.scss'], imports: [DoggoListComponent, DoggoRateComponent], }) export class MainDoggoComponent implements OnInit { doggoId = input(''); service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); private readonly destroyRef = inject(DestroyRef); ngOnInit(): void { 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
37. Easier to test @Component({ selector: 'app-main-doggo', templateUrl: './main-doggo.component.html', styleUrls: ['./main-doggo.component.scss'], imports: [DoggoListComponent, DoggoRateComponent], }) export class MainDoggoComponent implements OnInit { doggoId = input(''); service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); private readonly destroyRef = inject(DestroyRef); ngOnInit(): void { 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); templateUrl: ./main-doggo.component.html , 3 styleUrls: ['./main-doggo.component.scss'], 4 imports: [DoggoListComponent, DoggoRateComponent], 5 }) 6 export class MainDoggoComponent implements OnInit { 7 doggoId = input(''); 8 9 10 11 12 13 14 15 private readonly destroyRef = inject(DestroyRef); 16 17 ngOnInit(): void { 18 this.service1.myMethod().subscribe(()=> ...); 19 this.service2.myMethod().subscribe(()=> ...); 20 // 21
38. Easier to test @Component({ selector: 'app-main-doggo', templateUrl: './main-doggo.component.html', styleUrls: ['./main-doggo.component.scss'], imports: [DoggoListComponent, DoggoRateComponent], }) export class MainDoggoComponent implements OnInit { doggoId = input(''); service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); private readonly destroyRef = inject(DestroyRef); ngOnInit(): void { 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); @Component({ 1 selector: 'app-main-doggo', 2 templateUrl: './main-doggo.component.html', 3 styleUrls: ['./main-doggo.component.scss'], 4 imports: [DoggoListComponent, DoggoRateComponent], 5 }) 6 export class MainDoggoComponent implements OnInit { 7 doggoId = input(''); 8 9 10 11 12 13 14 15 private readonly destroyRef = inject(DestroyRef); 16 17 ngOnInit(): void { 18 ngOnInit(): void { this.service1.myMethod().subscribe(()=> ...); this.service2.myMethod().subscribe(()=> ...); // ... this.destroyRef.onDestroy(() => { this.store.stopListeningToRealtimeDoggoEvents(); }); } service4 = inject(Service4); 13 service5 = inject(Service5); 14 15 private readonly destroyRef = inject(DestroyRef); 16 17 18 19 20 21 22 23 24 25 26 27 rateDoggo(rating: number): void { 28 this.service3.myMethod().subscribe(()=> ...); 29 } 30
39. Easier to test @Component({ selector: 'app-main-doggo', templateUrl: './main-doggo.component.html', styleUrls: ['./main-doggo.component.scss'], imports: [DoggoListComponent, DoggoRateComponent], }) export class MainDoggoComponent implements OnInit { doggoId = input(''); service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); private readonly destroyRef = inject(DestroyRef); ngOnInit(): void { 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 service1 = inject(Service1); service2 = inject(Service2); service3 = inject(Service3); service4 = inject(Service4); service5 = inject(Service5); @Component({ 1 selector: 'app-main-doggo', 2 templateUrl: './main-doggo.component.html', 3 styleUrls: ['./main-doggo.component.scss'], 4 imports: [DoggoListComponent, DoggoRateComponent], 5 }) 6 export class MainDoggoComponent implements OnInit { 7 doggoId = input(''); 8 9 10 11 12 13 14 15 private readonly destroyRef = inject(DestroyRef); 16 17 ngOnInit(): void { 18 ngOnInit(): void { @Component({ 1 selector: 'app-main-doggo', 2 templateUrl: './main-doggo.component.html', 3 styleUrls: ['./main-doggo.component.scss'], 4 imports: [DoggoListComponent, DoggoRateComponent], 5 }) 6 export class MainDoggoComponent implements OnInit { 7 doggoId = input(''); 8 9 service1 = inject(Service1); 10 service2 = inject(Service2); 11 service3 = inject(Service3); 12 service4 = inject(Service4); 13 service5 = inject(Service5); 14 15 private readonly destroyRef = inject(DestroyRef); 16 17 18 rateDoggo(rating: number): void { this.service3.myMethod().subscribe(()=> ...); } skipDoggo(): void { this.service4.myMethod().subscribe(()=> ...); } selectDoggo(id: string): void { this.service5.myMethod().subscribe(()=> ...); } 22 this.destroyRef.onDestroy(() => { 23 this.store.stopListeningToRealtimeDoggoEvents(); 24 }); 25 } 26 27 28 29 30 31 32 33 34 35 36 37 38 } 39
40. Easier to test describe('MainDoggoComponent', () => { let component: MainDoggoComponent; let fixture: ComponentFixture<MainDoggoComponent>; let service1: Service1; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), ], providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
41. Easier to test describe('MainDoggoComponent', () => { let component: MainDoggoComponent; let fixture: ComponentFixture<MainDoggoComponent>; let service1: Service1; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), ], providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 let service1: Service1; describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18
42. Easier to test describe('MainDoggoComponent', () => { let component: MainDoggoComponent; let fixture: ComponentFixture<MainDoggoComponent>; let service1: Service1; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), ], providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 let service1: Service1; describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 let service1: Service1; 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 10 11 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 MockProvider(Service5), 19 provideRouter([]) 20
43. Easier to test describe('MainDoggoComponent', () => { let component: MainDoggoComponent; let fixture: ComponentFixture<MainDoggoComponent>; let service1: Service1; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), ], providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 let service1: Service1; describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 let service1: Service1; 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 10 11 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), MockProvider(Service5), provideRouter([]), ], imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 14 15 16 17 18 19 20 21 }).compileComponents(); 22 23 fixture = TestBed.createComponent(MainDoggoComponent); 24 component = fixture.componentInstance; 25
44. Easier to test describe('MainDoggoComponent', () => { let component: MainDoggoComponent; let fixture: ComponentFixture<MainDoggoComponent>; let service1: Service1; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), ], providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 let service1: Service1; describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 MainDoggoComponent, MockComponent(DoggoListComponent), MockComponent(DoggoRateComponent), describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 let service1: Service1; 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 10 11 12 ], 13 providers: [ 14 MockProvider(Service1), 15 MockProvider(Service2), 16 MockProvider(Service3), 17 MockProvider(Service4), 18 providers: [ MockProvider(Service1), MockProvider(Service2), MockProvider(Service3), MockProvider(Service4), describe('MainDoggoComponent', () => { 1 let component: MainDoggoComponent; 2 let fixture: ComponentFixture<MainDoggoComponent>; 3 4 let service1: Service1; 5 6 beforeEach(async () => { 7 await TestBed.configureTestingModule({ 8 imports: [ 9 MainDoggoComponent, 10 MockComponent(DoggoListComponent), 11 MockComponent(DoggoRateComponent), 12 ], 13 14 15 16 17 18 fixture = TestBed.createComponent(MainDoggoComponent); component = fixture.componentInstance; service1 = TestBed.inject(Service1); jest.spyOn(service1, "myMethod").mockReturnValue(of(...)) // Make everything ready fixture.detectChanges(); MockProvider(Service5), 19 provideRouter([]), 20 ], 21 }).compileComponents(); 22 23 24 25 26 27 28 29 30 31 32 }); 33 34 it('should create ', () => { 35 expect(component).toBeTruthy(); 36
45. Easier to test provides Overview
46. Easier to test provides Overview Exceptions
47. Exceptions
48. Exceptions Too much Bubbling
49. Exceptions Too much Bubbling Shell Component
50. Components
51. Components Inheritance of
52. @Component({ /* ... */ }) export class UserBaseComponent { // Shared Logic // Shared Inputs // ... } @Component({ /* ... */ }) export class AddUserComponent extends UserBaseComponent { // ... } @Component({ /* ... */ }) export class EditUserComponent extends UserBaseComponent { // ... } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
53. No Single Responsibility Hard to Test Complexity
54. @Injectable({ providedIn: "root" }) export class UserService { // Shared Logic // ... } @Component({ /* ... */ }) export class AddUserComponent { private userService = inject(UserService); // ... } @Component({ /* ... */ }) export class EditUserComponent { private userService = inject(UserService); // ... } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
55. Composition over inheritance
56. Composition over inheritance USe dependency INjection
57. Composition over inheritance USe dependency INjection Easier to Read, understand & Test
58. Code Organization
59. Code Organization Beauty of
60. project-root/ ├── app/ │ ├── header.component.ts │ ├── footer.component.ts │ ├── data.service.ts │ ├── utils.ts │ ├── old/ │ │ ├── old-helper.js │ │ └── unused-file.md │ ├── temp.component.ts │ ├── feature/ │ │ ├── feature.component.ts │ │ ├── styles.css │ │ └── random-script.js │ ├── helper.ts │ └── app.module.ts └── main.ts 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
61. project-root/ └── src/ ├── app/ │ ├── features/ │ │ ├── user/ │ │ │ ├── container │ │ │ ├── ui │ │ │ └── ... │ │ ├── dashboard/ │ │ │ ├── container │ │ │ ├── ui │ │ │ └── ... │ │ └── shopping-cart/ │ │ ├── container │ │ ├── ui │ │ └── ... │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
62. Easy to follow
63. Easy to follow Folders & Levels provide information!
64. Easy to follow Folders & Levels provide information! Lightweight and scalable
65. Architecture Route based
66. export const APP_ROUTES = [ ]; 1 2 3 project-root/ └── src/ ├── app/ │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8
67. export const APP_ROUTES = [ { path: 'users', // ... }, ]; 1 2 3 4 5 6 project-root/ └── src/ ├── app/ │ ├── features/ │ │ ├── users/ │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8 9 10
68. export const APP_ROUTES = [ { path: 'users', // ... }, { path: 'dashboard', // ... }, ]; 1 2 3 4 5 6 7 8 9 10 project-root/ └── src/ ├── app/ │ ├── features/ │ │ ├── users/ │ │ ├── dashboard/ │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8 9 10 11
69. export const APP_ROUTES = [ { path: 'users', // ... }, { path: 'dashboard', // ... }, { path: 'shopping-cart', // ... }, ]; 1 2 3 4 5 6 7 8 9 10 11 12 13 14 project-root/ └── src/ ├── app/ │ ├── features/ │ │ ├── users/ │ │ ├── dashboard/ │ │ └── shopping-cart/ │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8 9 10 11 12
70. export const APP_ROUTES = [ { path: 'users', // ... }, { path: 'dashboard', // ... }, { path: 'shopping-cart', // ... }, ]; 1 2 3 4 5 6 7 8 9 10 11 12 13 14 project-root/ └── src/ ├── app/ │ ├── features/ │ │ ├── users/ │ │ │ ├── container │ │ │ ├── ui │ │ │ └── ... │ │ ├── dashboard/ │ │ │ ├── container │ │ │ ├── ui │ │ │ └── ... │ │ └── shopping-cart/ │ │ ├── container │ │ ├── ui │ │ └── ... │ └── shared/ │ ├── util-auth │ ├── util-logging │ └── ... └── main.ts 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
71. Forms
72. "right" Form Type Template Reactive
73. "right" Form Type Signal based
74. Typed Forms @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(0), }); onSubmit() { // both values of the form are typed here console.log(this.myForm.getRawValue()); console.log(this.myForm.value); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
75. Typed Forms @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(0), }); onSubmit() { // both values of the form are typed here console.log(this.myForm.getRawValue()); console.log(this.myForm.value); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(0), }); @Component({ 1 /* ... */ 2 }) 3 export class FormGroupComponent { 4 private readonly formBuilder = inject(FormBuilder); 5 6 7 8 9 10 11 onSubmit() { 12 // both values of the form are typed here 13 console.log(this.myForm.getRawValue()); 14 console.log(this.myForm.value); 15 } 16 } 17
76. Typed Forms @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(0), }); onSubmit() { // both values of the form are typed here console.log(this.myForm.getRawValue()); console.log(this.myForm.value); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(0), }); @Component({ 1 /* ... */ 2 }) 3 export class FormGroupComponent { 4 private readonly formBuilder = inject(FormBuilder); 5 6 7 8 9 10 11 onSubmit() { 12 // both values of the form are typed here 13 console.log(this.myForm.getRawValue()); 14 console.log(this.myForm.value); 15 } 16 } 17 onSubmit() { // both values of the form are typed here console.log(this.myForm.getRawValue()); console.log(this.myForm.value); } @Component({ 1 /* ... */ 2 }) 3 export class FormGroupComponent { 4 private readonly formBuilder = inject(FormBuilder); 5 6 myForm = this.formBuilder.group({ 7 // ... 8 age: this.formBuilder.control(0), 9 }); 10 11 12 13 14 15 16 } 17
77. Abstract Control API
78. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
79. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
80. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valid: boolean invalid: boolean pending: boolean value: any | T 1 status: FormControlStatus 2 3 4 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
81. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valid: boolean invalid: boolean pending: boolean value: any | T 1 status: FormControlStatus 2 3 4 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 disabled: boolean enabled: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 6 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
82. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valid: boolean invalid: boolean pending: boolean value: any | T 1 status: FormControlStatus 2 3 4 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 disabled: boolean enabled: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 6 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 errors: ValidationErrors | null value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
83. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valid: boolean invalid: boolean pending: boolean value: any | T 1 status: FormControlStatus 2 3 4 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 disabled: boolean enabled: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 6 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 errors: ValidationErrors | null value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 pristine: boolean dirty: boolean touched: boolean untouched: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 9 10 11 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14
84. value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 status: FormControlStatus value: any | T 1 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valid: boolean invalid: boolean pending: boolean value: any | T 1 status: FormControlStatus 2 3 4 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 disabled: boolean enabled: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 6 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 errors: ValidationErrors | null value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 pristine: boolean dirty: boolean touched: boolean untouched: boolean value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 9 10 11 12 valueChanges: Observable<...> 13 statusChanges: Observable<...> 14 valueChanges: Observable<...> statusChanges: Observable<...> value: any | T 1 status: FormControlStatus 2 valid: boolean 3 invalid: boolean 4 pending: boolean 5 disabled: boolean 6 enabled: boolean 7 errors: ValidationErrors | null 8 pristine: boolean 9 dirty: boolean 10 touched: boolean 11 untouched: boolean 12 13 14
85. Validation
86. Validation .State .Errors
87. Validation Errors { required: true; } 1 2 3
88. Validation Errors export class AgeValidator { static ageValidator(control: AbstractControl<number>) { if (control.value < 0) { return { ageNotValid: true }; } if (control.value > 100) { return { ageNotValid: true }; } return null; } } 1 2 3 4 5 6 7 8 9 10 11 12 13
89. Validation Errors export class AgeValidator { static ageValidator(control: AbstractControl<number>) { if (control.value < 0) { return { ageNotValid: true }; } if (control.value > 100) { return { ageNotValid: true }; } return null; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 return { ageNotValid: true }; return { ageNotValid: true }; export class AgeValidator { 1 static ageValidator(control: AbstractControl<number>) { 2 if (control.value < 0) { 3 4 } 5 6 if (control.value > 100) { 7 8 } 9 10 return null; 11 } 12 } 13
90. Validation Errors { required: true, ageNotValid: true } 1 2 3 4
91. Validation @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(-10, [AgeValidator.ageValidator]), }); } 1 2 3 4 5 6 7 8 9 10 11
92. Validation @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group({ // ... age: this.formBuilder.control(-10, [AgeValidator.ageValidator]), }); } 1 2 3 4 5 6 7 8 9 10 11 `myForm` is `INVALID` `myForm.errors` is `null` `myForm.get('age').errors` would be `{ ageNotValid: true }` `myForm.get('age').errors` is `INVALID` 1 2 3 4
93. Cross Control Validation @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group( { // ... age: this.formBuilder.control(-10, [AgeValidator.ageValidator]), }, { validators: [RestrictAgeRoomValidator.ageRoomValidator], } ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
94. Cross Control Validation @Component({ /* ... */ }) export class FormGroupComponent { private readonly formBuilder = inject(FormBuilder); myForm = this.formBuilder.group( { // ... age: this.formBuilder.control(-10, [AgeValidator.ageValidator]), }, { validators: [RestrictAgeRoomValidator.ageRoomValidator], } ); } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 myForm = this.formBuilder.group( { validators: [RestrictAgeRoomValidator.ageRoomValidator], } ); @Component({ 1 /* ... */ 2 }) 3 export class FormGroupComponent { 4 private readonly formBuilder = inject(FormBuilder); 5 6 7 { 8 // ... 9 age: this.formBuilder.control(-10, [AgeValidator.ageValidator]), 10 }, 11 12 13 14 15 } 16
95. Cross Control Validation export class RestrictAgeRoomValidator { static ageRoomValidator(formGroup: AbstractControl) { const ageControl = formGroup.get("age"); const roomControl = formGroup.get("room"); if (!ageControl || !roomControl) { return null; } // return error or null } } 1 2 3 4 5 6 7 8 9 10 11 12 `myForm` is `INVALID` `myForm.errors` is `{ ... }` `myForm.get('age').errors` would be `...` `myForm.get('age').errors` is `...` 1 2 3 4
96. State
97. State IMpact of
98. You have to deal with State
99. @Component({ selector: 'app-root', template: ` <button (click)="increaseCounter()"> Increase counter </button> {{ counter }} `, }) export class App { counter = 0; increaseCounter(){ this.counter++; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
100. @Component({ selector: 'app-root', template: ` <button (click)="increaseCounter()"> Increase counter </button> {{ counter }} `, }) export class App { counter = 0; increaseCounter(){ this.counter++; } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 {{ counter }} counter = 0; @Component({ 1 selector: 'app-root', 2 template: ` 3 <button (click)="increaseCounter()"> 4 Increase counter 5 </button> 6 7 `, 8 }) 9 export class App { 10 11 12 increaseCounter(){ 13 this.counter++; 14 } 15 } 16
101. DOM IS State
102. @Component({ selector: 'app-root', template: ` <button (click)="increaseCounter()"> Increase counter </button> {{ counter() }} `, }) export class App { counter = signal(0); increaseCounter(){ this.counter.update((counter) => counter+1) } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
103. @Component({ selector: 'app-root', template: ` <button (click)="increaseCounter()"> Increase counter </button> {{ counter() }} `, }) export class App { counter = signal(0); increaseCounter(){ this.counter.update((counter) => counter+1) } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 {{ counter() }} counter = signal(0); @Component({ 1 selector: 'app-root', 2 template: ` 3 <button (click)="increaseCounter()"> 4 Increase counter 5 </button> 6 7 `, 8 }) 9 export class App { 10 11 12 increaseCounter(){ 13 this.counter.update((counter) => counter+1) 14 } 15 } 16
104. Component has State
105. export class SimpleFormControlComponent { valueAdded = output<string>(); myControl = new FormControl("my value"); submitted() { console.log(this.myControl.value); this.valueAdded.emit(this.myControl.value); } } 1 2 3 4 5 6 7 8 9 10 11 Closed Component State
106. export class TodoMainComponent { todos: Todo[] = []; addTodo(todo: Todo) { this.todos.push(todo); } deleteTodo(todoId: number) { this.todos = this.todos.filter(...); } } 1 2 3 4 5 6 7 8 9 10 11 container Component State
107. @Injectable({ providedIn: 'root' }) export class DashboardService { private dashboard: Dashboard = ...; getDashboard(): Observable<Dashboard> { return this.http.get<Dashboard>('api/dashboard').pipe( tap(dashboard => this.dashboard = dashboard) ); } updateDashboard(...): void { this.dashboard = ...; // or return this.http.put<Dashboard>('api/dashboard').pipe( tap(newDashboard => this.dashboard = newDashboard) ); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Feature State
108. @Injectable({ providedIn: 'root' }) export class DashboardService { private dashboard: Dashboard = ...; getDashboard(): Observable<Dashboard> { return this.http.get<Dashboard>('api/dashboard').pipe( tap(dashboard => this.dashboard = dashboard) ); } updateDashboard(...): void { this.dashboard = ...; // or return this.http.put<Dashboard>('api/dashboard').pipe( tap(newDashboard => this.dashboard = newDashboard) ); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 private dashboard: Dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 Feature State
109. @Injectable({ providedIn: 'root' }) export class DashboardService { private dashboard: Dashboard = ...; getDashboard(): Observable<Dashboard> { return this.http.get<Dashboard>('api/dashboard').pipe( tap(dashboard => this.dashboard = dashboard) ); } updateDashboard(...): void { this.dashboard = ...; // or return this.http.put<Dashboard>('api/dashboard').pipe( tap(newDashboard => this.dashboard = newDashboard) ); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 private dashboard: Dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 tap(dashboard => this.dashboard = dashboard) @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 Feature State
110. @Injectable({ providedIn: 'root' }) export class DashboardService { private dashboard: Dashboard = ...; getDashboard(): Observable<Dashboard> { return this.http.get<Dashboard>('api/dashboard').pipe( tap(dashboard => this.dashboard = dashboard) ); } updateDashboard(...): void { this.dashboard = ...; // or return this.http.put<Dashboard>('api/dashboard').pipe( tap(newDashboard => this.dashboard = newDashboard) ); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 private dashboard: Dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 tap(dashboard => this.dashboard = dashboard) @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 this.dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 Feature State
111. @Injectable({ providedIn: 'root' }) export class DashboardService { private dashboard: Dashboard = ...; getDashboard(): Observable<Dashboard> { return this.http.get<Dashboard>('api/dashboard').pipe( tap(dashboard => this.dashboard = dashboard) ); } updateDashboard(...): void { this.dashboard = ...; // or return this.http.put<Dashboard>('api/dashboard').pipe( tap(newDashboard => this.dashboard = newDashboard) ); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 private dashboard: Dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 tap(dashboard => this.dashboard = dashboard) @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 this.dashboard = ...; @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 tap(newDashboard => this.dashboard = newDashboard) 17 ); 18 } 19 } 20 tap(newDashboard => this.dashboard = newDashboard) @Injectable({ providedIn: 'root' }) 1 export class DashboardService { 2 private dashboard: Dashboard = ...; 3 4 getDashboard(): Observable<Dashboard> { 5 return this.http.get<Dashboard>('api/dashboard').pipe( 6 tap(dashboard => this.dashboard = dashboard) 7 ); 8 } 9 10 updateDashboard(...): void { 11 this.dashboard = ...; 12 13 // or 14 15 return this.http.put<Dashboard>('api/dashboard').pipe( 16 17 ); 18 } 19 } 20 Feature State
112. @Injectable({ providedIn: "root" }) export class AuthService { private isAuthenticated = signal<boolean>(false); isAuthenticated = this.isAuthenticated.asReadOnly(); login() { // ... this.isAuthenticated.set(true); } logout() { // ... this.isAuthenticated.set(false); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Application State
113. Route has State
114. http://localhost:4200/users?page=1&count=30&sort=asc
115. State impacts Architecture
116. src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10
117. src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10 │ ├── dashboard/ src/ 1 └── app/ 2 ├── features/ 3 4 │ │ └── ... 5 │ └── profile/ 6 │ └── ... 7 └── shared/ 8 ├── util-auth 9 └── ... 10
118. src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10 │ ├── dashboard/ src/ 1 └── app/ 2 ├── features/ 3 4 │ │ └── ... 5 │ └── profile/ 6 │ └── ... 7 └── shared/ 8 ├── util-auth 9 └── ... 10 │ └── profile/ src/ 1 └── app/ 2 ├── features/ 3 │ ├── dashboard/ 4 │ │ └── ... 5 6 │ └── ... 7 └── shared/ 8 ├── util-auth 9 └── ... 10
119. src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10 │ ├── dashboard/ src/ 1 └── app/ 2 ├── features/ 3 4 │ │ └── ... 5 │ └── profile/ 6 │ └── ... 7 └── shared/ 8 ├── util-auth 9 └── ... 10 │ └── profile/ src/ 1 └── app/ 2 ├── features/ 3 │ ├── dashboard/ 4 │ │ └── ... 5 6 │ └── ... 7 └── shared/ 8 ├── util-auth 9 └── ... 10 └── shared/ ├── util-auth src/ 1 └── app/ 2 ├── features/ 3 │ ├── dashboard/ 4 │ │ └── ... 5 │ └── profile/ 6 │ └── ... 7 8 9 └── ... 10
120. "dashboard": { { 1 2 // ... 3 }, 4 "profile": { 5 // ... 6 }, 7 "shared": { 8 "auth": { ... } 9 }, 10 } 11 src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10
121. "dashboard": { { 1 2 // ... 3 }, 4 "profile": { 5 // ... 6 }, 7 "shared": { 8 "auth": { ... } 9 }, 10 } 11 "profile": { { 1 "dashboard": { 2 // ... 3 }, 4 5 // ... 6 }, 7 "shared": { 8 "auth": { ... } 9 }, 10 } 11 src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10
122. "dashboard": { { 1 2 // ... 3 }, 4 "profile": { 5 // ... 6 }, 7 "shared": { 8 "auth": { ... } 9 }, 10 } 11 "profile": { { 1 "dashboard": { 2 // ... 3 }, 4 5 // ... 6 }, 7 "shared": { 8 "auth": { ... } 9 }, 10 } 11 "shared": { "auth": { ... } { 1 "dashboard": { 2 // ... 3 }, 4 "profile": { 5 // ... 6 }, 7 8 9 }, 10 } 11 src/ └── app/ ├── features/ │ ├── dashboard/ │ │ └── ... │ └── profile/ │ └── ... └── shared/ ├── util-auth └── ... 1 2 3 4 5 6 7 8 9 10
123. State impacts components
124. Container & Presentational
125. Container & Presentational Makes container "Listening" to State Changes
126. Container & Presentational Makes container "Listening" to State Changes Less Logic in COmponents
127. Less Logic in COmponents
128. GET THE LOGIC Out of Components
129. export class ProductsComponent implements OnInit { private readonly store = inject(Store); readonly productsByCategories = this.store.selectSignal( selectProductsByCategories, ); ngOnInit(): void { this.store.dispatch(ProductsActions.loadProducts()); } onProductClicked(id: string): void { this.store.dispatch(ProductsActions.navigateToDetail({ id })); } onCartClicked(product: Product): void { this.store.dispatch(CheckoutActions.addProduct({ product })); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
130. export class ProductsComponent implements OnInit { private readonly store = inject(Store); readonly productsByCategories = this.store.selectSignal( selectProductsByCategories, ); ngOnInit(): void { this.store.dispatch(ProductsActions.loadProducts()); } onProductClicked(id: string): void { this.store.dispatch(ProductsActions.navigateToDetail({ id })); } onCartClicked(product: Product): void { this.store.dispatch(CheckoutActions.addProduct({ product })); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 readonly productsByCategories = this.store.selectSignal( selectProductsByCategories, ); this.store.dispatch(ProductsActions.loadProducts()); this.store.dispatch(ProductsActions.navigateToDetail({ id })); this.store.dispatch(CheckoutActions.addProduct({ product })); export class ProductsComponent implements OnInit { 1 private readonly store = inject(Store); 2 3 4 5 6 7 ngOnInit(): void { 8 9 } 10 11 onProductClicked(id: string): void { 12 13 } 14 15 onCartClicked(product: Product): void { 16 17 } 18 } 19
131. export class ProductsComponent implements OnInit { private readonly store = inject(Store); readonly productsByCategories = this.store.productsByCategories(); ngOnInit(): void { this.store.loadProducts(); } onProductClicked(id: string): void { this.store.navigateToDetail({ id }); } onCartClicked(product: Product): void { this.store.addProduct({ product }); } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
132. describe('ProductsComponent', () => { let component: ProductsComponent; let fixture: ComponentFixture<ProductsComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); fixture = TestBed.createComponent(ProductsComponent); component = fixture.componentInstance; fixture.detectChanges(); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
133. describe('ProductsComponent', () => { let component: ProductsComponent; let fixture: ComponentFixture<ProductsComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); fixture = TestBed.createComponent(ProductsComponent); component = fixture.componentInstance; fixture.detectChanges(); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); describe('ProductsComponent', () => { 1 let component: ProductsComponent; 2 let fixture: ComponentFixture<ProductsComponent>; 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 fixture = TestBed.createComponent(ProductsComponent); 18 component = fixture.componentInstance; 19 fixture.detectChanges(); 20 }); 21 }); 22
134. describe('ProductsComponent', () => { let component: ProductsComponent; let fixture: ComponentFixture<ProductsComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); fixture = TestBed.createComponent(ProductsComponent); component = fixture.componentInstance; fixture.detectChanges(); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); describe('ProductsComponent', () => { 1 let component: ProductsComponent; 2 let fixture: ComponentFixture<ProductsComponent>; 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 fixture = TestBed.createComponent(ProductsComponent); 18 component = fixture.componentInstance; 19 fixture.detectChanges(); 20 }); 21 }); 22 describe('ProductsComponent', () => { let component: ProductsComponent; let fixture: ComponentFixture<ProductsComponent>; beforeEach(async () => { await TestBed.configureTestingModule({ imports: [ProductsComponent], providers: [ MockProvider(Store, { productsByCategories: signal(...), loadProducts: jest.fn(), navigateToDetail: jest.fn(), addProduct: jest.fn(), }), ], }).compileComponents(); fixture = TestBed.createComponent(ProductsComponent); component = fixture.componentInstance; fixture.detectChanges(); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
135. Impacts State Routing
136. { "dashboard": { // ... }, "profile": { // ... }, "shared": { "auth": { ... } }, } 1 2 3 4 5 6 7 8 9 10 11 export const APP_ROUTES: Routes = [ { path: 'dashboard', loadChildren: () => // ... }, { path: 'profile', loadChildren: () => // ... }, ]; 1 2 3 4 5 6 7 8 9 10
137. State provides Guidance
138. "Why are you the most expensive yet the cheapest?"
139. I wish I knew
140. I wish I knew Container Presentational
141. I wish I knew Code Organization
142. I wish I knew Forms & Validation
143. I wish I knew State Management
145. Team Work
147. Learning
148. Learning Together
149. Thank You