* implementing turning off camera (setting deviceId to null; showWebc…

…am to false; and most importantly releasing resources by calling nextWebcam.complete() on a subject)

* adding unit test

src/app/app.component.spec.ts

@@ -15,15 +15,32 @@ describe('AppComponent', () => {
       ]
     }).compileComponents();
   }));
+
   it('should create the app', waitForAsync(() => {
     const fixture = TestBed.createComponent(AppComponent);
     const app = fixture.debugElement.componentInstance;
     expect(app).toBeTruthy();
   }));
+
   it('should render title in a h1 tag', waitForAsync(() => {
     const fixture = TestBed.createComponent(AppComponent);
     fixture.detectChanges();
     const compiled = fixture.debugElement.nativeElement;
     expect(compiled.querySelector('h1').textContent).toContain('ngx-webcam Demo');
   }));
+
+  it('closing camera connection when turning off camera', waitForAsync(() => {
+    const fixture = TestBed.createComponent(AppComponent);
+    const app = fixture.debugElement.componentInstance;
+    app.deviceId = '111';
+    app.showWebcam = true;
+    const compiled = fixture.debugElement.nativeElement;
+
+    app.turnOffCamera();
+
+    expect(app.deviceId).toBeNull();
+    expect(app.showWebcam).toBeFalse();
+    expect(compiled.querySelector('webcam')).toBeNull();
+  }));
+
 });

src/app/app.component.ts

@@ -36,6 +36,15 @@ export class AppComponent implements OnInit {
 
   public toggleWebcam(): void {
     this.showWebcam = !this.showWebcam;
+    if (!this.showWebcam) {
+      this.turnOffCamera();
+    }
+  }
+
+  public turnOffCamera(): void {
+    this.deviceId = null;
+    this.showWebcam = false;
+    this.nextWebcam.complete();
   }
 
   public handleInitError(error: WebcamInitError): void {