Separate Directive Scope Angular2

Question

I've tried looking at some similar questions here at SO but couldn't find a way to solve my problem.

There's a countdown @Directive() that takes in a couple inputs and counts down. The counting down part works, except I'm running into a problem where all the selectors are running / emitting the same numbers before going onto the next countdown. How would I get them to separately countdown using their own parameters and running concurrently?

Plunkr

run() code in app.component.ts

run() {
    var _this = this;
    clearInterval(_this._timer);
    var counting = 0;
    var incrementFactor = 0;
    var increment = 1;

    if (!isNaN(_this._duration) && !isNaN(_this._step) && !isNaN(_this._countFrom) && !isNaN(_this._countTo)) {
        counting    = Math.round(_this._countFrom);
        incrementFactor = Math.round(Math.abs(_this._countTo - _this._countFrom) / ((_this._duration * 1000) / _this._step));
        increment       = (incrementFactor < 1) ? 1 : incrementFactor

        _this.countToChange.emit(counting);

        _this._timer = setInterval(function() {
            if (_this._countTo < _this._countFrom) {
                if (counting <= _this._countTo) {
                    clearInterval(_this._timer);
                    _this.countToChange.emit(_this._countTo);
                } else {
                    _this.countToChange.emit(counting);
                    counting -= increment;
                }
            }
        }, _this._step);
    }
}

Answer 1

The problem is with your component. You used the same variable 'counting' for all 3 directives.

It works if you use 3 different component level variables as follows:

Here is an updated version of your plunk https://plnkr.co/edit/PrwF8gYrl5AYCB0XcUsg?p=preview

@Component({
    selector: 'my-app',
    template: `
    <countDown [step]="100" [countFrom]="100" [countTo]=0 [duration]="2" (countToChange)="count1 = $event">{{ count1 }}</countDown>
    <countDown [step]="100" [countFrom]="1000" [countTo]=0 [duration]="4" (countToChange)="count2 = $event">{{ count2 }}</countDown>
    <countDown [step]="100" [countFrom]="10000" [countTo]=0 [duration]="20" (countToChange)="count3 = $event">{{ count3 }}</countDown>
    `,
    directives: [countDown]
})
export class AppComponent {
  public count1:number;
  public count2:number;
  public count3:number;
}