Impossible to use ion-slides methods (No provider for ChangeDetectorRef)

Question

I want to use ion-slides method getActiveIndex() but when I import ion-slides as a provider, I have this error :

NullInjectorError: No provider for ChangeDetectorRef!

I don't know why I have to add this to providers. Even if I add this, I have the other provider: ElementRef...

If you have a look at my code, could you tell me if I'm doing something wrong?

thanks!

liste.page.ts :

import {IonSlides} from '@ionic/angular';

@Component({
  selector: 'app-liste',
  templateUrl: './liste.page.html',
  styleUrls: ['./liste.page.scss'],
})

export class ListePage {

  constructor(private ionSlides: IonSlides) { }

  slideChanged() {
     console.log(this.ionSlides.getActiveIndex());
    }

}

liste.page.html:

<ion-slides [options]="sliderConfig" (ionSlideTransitionEnd)="slideChanged()">
  <ion-slide *ngFor="let item of items; let i = index">
   {{item.name}}
  </ion-slide>
</ion-slides

Ionic Info:

ionic (Ionic CLI)             : 4.9.0 
Ionic Framework               : @ionic/angular 4.1.2
@angular-devkit/build-angular : 0.13.6
@angular-devkit/schematics    : 7.2.4
@angular/cli                  : 7.3.6
@ionic/angular-toolkit        : 1.4.1

Answer 1

In your liste.page.html use:

<ion-slides pager="true" #slides>

Then you can reference it in your liste.page.ts file with:

import {IonSlides} from '@ionic/angular';
import {ViewChild} from '@angular/core';  // <----

[...] 

export class ListePage {
@ViewChild('slides', { read: IonSlides }) slides: IonSlides; // <----

Then you have access to slides and can call getActiveIndex();

slideChanged() {
  console.log(this.slides.getActiveIndex());
}