Callback function by directive

Asked Aug 06 '18 at 15:33

Active Aug 06 '18 at 15:33

Viewed 203 times

I need to call the function after *ngFor is finished. For it i make like this:

@Directive({
  selector:'[method]'
})
export class CallbackDirective implements OnDestroy{
  private called:boolean = false;
  @Input('method') method: Function;
  @Input('clause')
  set condition(value:any){
    if(!value || value == false) return;

    if(!this.called && this.method){
      this.method();
      this.called = true;
    }
  }

  constructor(){}
}

html

<div class="media" *ngFor="let item of items; let i = index; let last = last" [method]="navigate" [clause]="last">

code in componet

id:number;
constructor(){
  this.id = 0; //some value
}

navigate(){
  if(this.id)
    //do something
}

I have a problem - when call "navigate"'s function param "id" is undefined. How I get value "id" in navigate method?

asked Aug 06 '18 at 15:33

Dmitrii Vashchenko

Possible duplicate of [How to access the correct \`this\` inside a callback?](https://stackoverflow.com/questions/20279484/how-to-access-the-correct-this-inside-a-callback) – ConnorsFan Aug 06 '18 at 16:03
Define `navigate` as an arrow function: `navigate = (): void => { ... }`. – ConnorsFan Aug 06 '18 at 16:03
That;s solved for me! Thanks! – Dmitrii Vashchenko Aug 07 '18 at 06:15

Callback function by directive

0 Answers0