下一个和上一个不使用angular2物化旋转木马

我想使用next和prev功能从一张幻灯片切换到另一张幻灯片。我不能使用JQuery，所以“$”不是一个选项。我向旋转木马添加了一个[materializeActions]属性，并在组件中设置了事件发射器。我知道有些东西在工作，因为当我调用“actions.emit（'next'）时，我没有收到错误；但是，当我调用“actions.emit（'badFunc'）时，我确实收到错误

此代码来自angular2 materialize提供的示例。我只添加了一个按钮来下一步移动

<div #carousel class="carousel" [ngClass]="{ 'initialized': showInitialized }"  materialize="carousel" [materializeActions]="actions">
<a *ngFor="let url of imageURLs" class="carousel-item"><img [src]="url"></a>
</div> 

<button (click)="next()">Next</button>

下一个

来自组件的代码：

import { Component, OnInit, ViewChild, EventEmitter } from '@angular/core';

@Component({
  selector: 'app-dashboard',
  templateUrl: './dashboard.component.html',
  styleUrls: ['./dashboard.component.css']
})
export class DashboardComponent implements OnInit {

  public modules: IModule[];

  @ViewChild('carousel') carouselElement;
  actions = new EventEmitter<string>();

  constructor() {

  }

 imageURLs = [
    'https://image.shutterstock.com/display_pic_with_logo/1264645/364153082/stock-photo-asian-girl-in-sunflower-field-364153082.jpg',
    'https://image.shutterstock.com/display_pic_with_logo/1264645/298927574/stock-photo-a-young-traveler-girl-sit-on-the-wooden-bridge-in-halong-bay-and-enjoy-the-beauty-of-seascape-298927574.jpg',
    'https://image.shutterstock.com/display_pic_with_logo/1264645/298757792/stock-photo-a-young-traveler-girl-sit-on-the-top-of-mountain-in-halong-bay-and-enjoy-the-beauty-of-seascape-298757792.jpg',
    'https://image.shutterstock.com/display_pic_with_logo/2565601/411902890/stock-photo-ha-long-bay-scenic-view-hanoi-vietnam-411902890.jpg',
    'https://image.shutterstock.com/display_pic_with_logo/2565601/413207668/stock-photo-the-temple-of-literature-in-hanoi-vietnam-the-chinese-words-is-poem-of-thie-temple-and-templs-s-413207668.jpg'
  ];

  ngOnInit() {

     // example of a hacky way to add an image to the carousel dynamically
    window.setTimeout(() => {
      this.imageURLs = [this.imageURLs[0], ...this.imageURLs]; // duplicate the first iamge
      this.carouselElement.nativeElement.classList.toggle('initialized');
      this.actions.emit('carousel');
    }, 1000);
  }

  next() {

    // Move to next slide. This is not working
    this.actions.emit('next');
  }

}

从'@angular/core'导入{Component，OnInit，ViewChild，EventEmitter}；
@组成部分({
选择器：“应用程序仪表板”，
templateUrl:“./dashboard.component.html”，
样式URL:['./dashboard.component.css']
})
导出类DashboardComponent实现OnInit{
公共模块：IModule[]；
@ViewChild（“旋转木马”）旋转木马元素；
actions=neweventemitter（）；
构造函数（）{
}
ImageURL=[
'https://image.shutterstock.com/display_pic_with_logo/1264645/364153082/stock-photo-asian-girl-in-sunflower-field-364153082.jpg',
'https://image.shutterstock.com/display_pic_with_logo/1264645/298927574/stock-photo-a-young-traveler-girl-sit-on-the-wooden-bridge-in-halong-bay-and-enjoy-the-beauty-of-seascape-298927574.jpg',
'https://image.shutterstock.com/display_pic_with_logo/1264645/298757792/stock-photo-a-young-traveler-girl-sit-on-the-top-of-mountain-in-halong-bay-and-enjoy-the-beauty-of-seascape-298757792.jpg',
'https://image.shutterstock.com/display_pic_with_logo/2565601/411902890/stock-photo-ha-long-bay-scenic-view-hanoi-vietnam-411902890.jpg',
'https://image.shutterstock.com/display_pic_with_logo/2565601/413207668/stock-photo-the-temple-of-literature-in-hanoi-vietnam-the-chinese-words-is-poem-of-thie-temple-and-templs-s-413207668.jpg'
];
恩戈尼尼特（）{
//将图像动态添加到旋转木马的黑客方法示例
window.setTimeout（（）=>{
this.imageURLs=[this.imageURLs[0]，…this.imageURLs]；//复制第一个iamge
this.carouselement.nativeElement.classList.toggle（'initialized'）；
this.actions.emit（'carousel'）；
}, 1000);
}
下一个（）{
//移动到下一张幻灯片。这不起作用
this.actions.emit（'next'）；
}
}

我找到了答案。它需要如下所示：

this.actions.emit({ action: 'carousel', params: ['next'] });
this.actions.emit({ action: 'carousel', params: ['prev'] });