在沒有jQuery的Angular 5上滾動觸發活動類

Question

我需要有關在滾動應用程序時如何觸發添加類而不使用jQuery的說明。

我有這種結構的側面菜單

<div class="menu">
  <div class="menu-item">
    <div class="line"></div>
    <span class="home">Home</span>
  </div>
  <div class="menu-item">
    <div class="line"></div>
    <span class="other">Venture Creation</span>
  </div>
  <div class="menu-item">
    <div class="line"></div>
    <span class="other">Product Studio</span>
  </div>
  <div class="menu-item">
    <div class="line"></div>
    <span class="other">Portfolio</span>
  </div>
  <div class="menu-item">
    <div class="line"></div>
    <span class="other">what i do</span>
  </div>
  <div class="menu-item">
    <div class="line"></div>
    <span class="other">Stay in Touch</span>
  </div>
</div>

我有六個部分，高度為100vh，當我在特定部分上滾動時，我需要觸發活動類，因此，當我在部分上（例如）時，我的活動類在以下位置：

 <div class="menu-item">
    <div class="line"></div>
    <span class="other">Portfolio</span>
  </div>

我的問題與另一個問題有關，當我在特定部分中時，我還需要觸發一些其他事件。 想法是我在背景上觸發動畫，以便獲得如下網頁所示的效果： https : //sonikpass.com/

我有這樣的結構：

<div class="global-background">
 <div class="top-part">
  <img class="img-one-top" src="../assets/images/brain1-01.svg" alt="" />
  <img class="img-two-top" src="../assets/images/whoiam1-01.svg" alt="" />
  <img class="img-three-top" src="../assets/images/whatidid1-01.svg" alt="" />
  <img class="img-four-top" src="../assets/images/whatido1-01.svg" alt="" />
  <img class="img-five-top" src="../assets/images/connect1-01.svg" alt="" />
 </div>
 <div class="bottom-part">
  <img class="img-one-bottom" src="../assets/images/brain2-02.svg" alt="" />
  <img class="img-two-bottom" src="../assets/images/whoiam2-02.svg" alt="" />
  <img class="img-three-bottom" src="../assets/images/whatidid2-02.svg" alt="" />
  <img class="img-four-bottom" src="../assets/images/whatido2-02.svg" alt="" />
  <img class="img-five-bottom" src="../assets/images/connect2-02.svg" alt="" />
 </div>
</div>

我已經在CSS中為SlidingInLeft和SlidingInRight做過動畫，所以我只需要包裝這些東西並實現它們。

最好的解決方案是什么？

Answer 1

可以使用directive通過以下方式監聽mousewheel事件來實現此目的，

指令代碼

@Directive({
    selector: '[wheel]'
})
export class WheelDirective implements OnInit{
    constructor(
        private renderer: Renderer2,
        private el: ElementRef
    ){}
    ngOnInit(){
      Array.from(this.el.nativeElement.children).forEach((item,index)=>{
        if(index!==0){
          item.classList.add('hidden');
        }
      })
    }

    @HostListener('mousewheel', ['$event']) onMousewheel(event) {
      let parentDiv = event.srcElement.parentElement;
      console.log(parentDiv);
      let childNodes = Array.from(parentDiv.children);
      let currentIndex=-1;
      if(parentDiv && parentDiv.children){
      childNodes.forEach((item,index)=>{
        if(item!==event.srcElement){
          item.classList.add('hidden');  
        }else{
          item.classList.add('hidden');  
          currentIndex = index
        }

      });
      if(currentIndex===(childNodes.length -1)){
        currentIndex=0;
      }
      childNodes[currentIndex+1].classList.remove('hidden');
      }
}

的HTML

<div class="top-part" wheel>
  <img class="img-one-top" src="https://lorempixel.com/400/200" alt="" />
  <img class="img-two-top" src="https://lorempixel.com/400/201" alt="" />
  <img class="img-three-top" src="https://lorempixel.com/400/202" alt="" />
  <img class="img-four-top" src="https://lorempixel.com/400/300" alt="" />
  <img class="img-five-top" src="https://lorempixel.com/400/600" alt="" />
</div>

現場演示