Dynamic update [checked] in Angular2

Question

componentA.ts

@Input() array;

<input type="checkbox" [checked]="array | contains: value"/>
<label>{{array.length}}</label>

componentB.ts

@Component({
  selector: 'app-component-b',
  templateUrl: './app.component-b.html'
})
export class AppComponentB {
  array = [1, 2, 3];
}

I am updating arrayin some other components. While labelupdating the length of the array correctly, the checkbox does not seem to be updating. contains- this is just a simple channel that checks if it is a valuepart array. I put a console.login the tube containsand got the result only on the first page, not when changing array. Why is this?

Thank..

Answer 1

, push , , , (array value )

:

1)

this.array = this.array.concat(4)

this.array = [...this.array, 4];

Plunker

2)

@Pipe({name: 'contains', pure: false})
export class ContainsPipe implements PipeTransform {

Plunker

.

• NgFor Pipe Angular2
• Angular 2 , 1, 5
• https://angular.io/docs/ts/latest/guide/pipes.html