Angular 2使用RC 5中新的动画支持，一个接一个地动画*ngFor列表项

Question

我有一个组件，它从服务器获取项目列表，然后在模板中使用*ngFor显示该列表。

我希望列表显示一些动画，但一个接一个。我的意思是，每个列表项都应该一个接一个地动画化。

我正在尝试这样做:

import { Component, Input, trigger, state, animate, transition, style } from '@angular/core';
@Component({
    selector: 'list-item',
    template: ` <li  @flyInOut="'in'">{{item}}</li>`,
    animations: [
        trigger('flyInOut', [
            state('in', style({ transform: 'translateX(0)' })),
            transition('void => *', [
                style({ transform: 'translateX(-100%)' }),
                animate(100)
            ]),
            transition('* => void', [
                animate(100, style({ transform: 'translateX(100%)' }))
            ])
        ])
    ]
})
export class ListItemComponent {
    @Input() item: any;
}

和在我的列表组件模板我使用它像:

<ul>
    <li *ngFor="let item of list;">
     <list-item [item]="item"></list-item>
    </li>
</ul>

它的作用是一次显示整个列表。

Answer 1

我在文档中找不到stagger对ngFor的支持，但是现在有了animation.done events ，可以用来生成 staggering ngFor

StackBlitz

@Component({
  selector: 'my-app',
  template: `
    <ul>
    <li *ngFor="let hero of staggeringHeroes; let i = index"
        (@flyInOut.done)="doNext()"
        [@flyInOut]="'in'" (click)="removeMe(i)">
      {{hero}}
    </li>
  </ul>
  `,
  animations: [
  trigger('flyInOut', [
    state('in', style({transform: 'translateX(0)'})),
    transition('void => *', [
      animate(300, keyframes([
        style({opacity: 0, transform: 'translateX(-100%)', offset: 0}),
        style({opacity: 1, transform: 'translateX(15px)',  offset: 0.3}),
        style({opacity: 1, transform: 'translateX(0)',     offset: 1.0})
      ]))
    ]),
    transition('* => void', [
      animate(300, keyframes([
        style({opacity: 1, transform: 'translateX(0)',     offset: 0}),
        style({opacity: 1, transform: 'translateX(-15px)', offset: 0.7}),
        style({opacity: 0, transform: 'translateX(100%)',  offset: 1.0})
      ]))
    ])
  ])
]
})
export class App {
  heroes: any[] = ['Alpha', 'Bravo', 'Charlie', 'Delta', 'Echo', 'Foxtrot', 'Golf', 'Hotel', 'India'];
  next: number = 0;
  staggeringHeroes: any[] = [];
  constructor(){
    this.doNext();
  }
  doNext() {
    if(this.next < this.heroes.length) {
      this.staggeringHeroes.push(this.heroes[this.next++]);
    }
  }
  removeMe(i) {
    this.staggeringHeroes.splice(i, 1);
  }
}

Answer 2

为了使用angular2动画，我为迭代项设置了一个state属性，然后为mouseover和mouseout函数设置了一个切换函数。这样，每个项目都封装了它的动画状态，然后我可以根据需要更改它

<li
   *ngFor="let item of itemsList"
   (mouseover)="toogleAnimation(item)"
   (mouseout)="toogleAnimation(item)"
>{{ item.name }}
  <div class="animation_wrapper" [@slideInOut]="item.state">
    <span class="glyphicon glyphicon-refresh"></span>
    <span class="glyphicon glyphicon-trash"></span>
  </div>
</li>

Answer 3

您想要的列表中每个项目之间的时间，请参阅此代码。将。css文件更改为。scss

像这样https://codepen.io/jhenriquez856/pen/baPagq

$total-items: 5;
body {
  font-family: sans-serif;
  background: #111;
  color: #fff;
}
ul {
  width: 300px;
  left: 50%;
  margin-top: 25px;
  margin-left: -150px;
  
  position: absolute;
}
li {
  position: relative;
  display: block;
  border: 1px solid hotpink;
  margin-bottom: 5px;
  padding: 10px;
  text-align: center;
  text-transform: uppercase;
  animation: fadeIn 0.5s linear;
  animation-fill-mode: both;
}
// Set delay per List Item
@for $i from 1 through $total-items {
  li:nth-child(#{$i}) {
    animation-delay: .25s * $i;
  }
}
// Keyframe animation
@-webkit-keyframes fadeIn {
  0% {
    opacity: 0;
  }
  75% {
    opacity: 0.5;
  }
  100% {
    opacity: 1;
  }
}

<ul>
  <li>item 1</li>
  <li>item 2</li>
  <li>item 3</li>
  <li>item 4</li>
  <li>item 5</li>
</ul>