Bryan - 11 months ago 60

Javascript 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 seperately 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 Source

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;
}
```