feat(challenge 39): implement injection token for timer configuration

Author: truonghungit

apps/angular/39-injection-token/src/app/phone.component.ts

@@ -1,9 +1,11 @@
 import { Component } from '@angular/core';
 import { TimerContainerComponent } from './timer-container.component';
+import { TIMER } from './timer-provider';
 
 @Component({
   selector: 'app-phone',
   imports: [TimerContainerComponent],
+  providers: [{ provide: TIMER, useValue: 2000 }],
   template: `
     <div class="flex gap-2">
       Phone Call Timer:

apps/angular/39-injection-token/src/app/timer-container.component.ts

@@ -1,5 +1,5 @@
-import { Component } from '@angular/core';
-import { DEFAULT_TIMER } from './data';
+import { Component, inject } from '@angular/core';
+import { TIMER } from './timer-provider';
 import { TimerComponent } from './timer.component';
 @Component({
   selector: 'timer-container',
@@ -16,5 +16,5 @@ import { TimerComponent } from './timer.component';
   },
 })
 export class TimerContainerComponent {
-  timer = DEFAULT_TIMER;
+  timer = inject(TIMER);
 }

apps/angular/39-injection-token/src/app/timer-provider.ts

@@ -0,0 +1,7 @@
+import { InjectionToken } from '@angular/core';
+import { DEFAULT_TIMER } from './data';
+
+export const TIMER = new InjectionToken<number>('timer', {
+  providedIn: 'root',
+  factory: () => DEFAULT_TIMER,
+});

apps/angular/39-injection-token/src/app/timer.component.ts

@@ -1,7 +1,7 @@
-import { Component } from '@angular/core';
+import { Component, inject } from '@angular/core';
 import { toSignal } from '@angular/core/rxjs-interop';
 import { interval } from 'rxjs';
-import { DEFAULT_TIMER } from './data';
+import { TIMER } from './timer-provider';
 
 @Component({
   selector: 'timer',
@@ -10,5 +10,5 @@ import { DEFAULT_TIMER } from './data';
   `,
 })
 export class TimerComponent {
-  timer = toSignal(interval(DEFAULT_TIMER));
+  timer = toSignal(interval(inject(TIMER)));
 }