无法处理动画 - 返回零元素

时间:2017-09-21 20:16:52

标签: angular typescript angular-animations

我为数据创建服务后,动画停止了工作。看起来像是因为当页面最初加载时,ng-repeat中没有元素(因为它正在获取数据)。似乎是THISTHIS的类似案例:

错误:

ERROR Error: Unable to process animations due to the following failed trigger transitions @listAnimation has failed due to:

- `query(":enter")` returned zero elements. (Use `query(":enter", { optional: true })` if you wish to allow this.)

动画:

trigger('listAnimation', [
      transition('* => *', [
        query(':enter', style({ opacity: 0}), { optional: true }),
        query(':enter', stagger('150ms', [
          animate('.5s ease-in', keyframes([
            style({ opacity: 0, /*transform: 'translateY(-75px)',*/ offest: 0}),
            style({ opacity: .5, /*transform: 'translateY(35px)',*/ offest: .3}),
            style({ opacity: 1, /*transform: 'translateY(0px)',*/ offest: 1})
          ]))
        ]))
      ])
    ])

HTML:

<div [@listAnimation]>
    <div *ngFor="let member of members" class="member-card">
      member info goes here...
    </div>
</div>

现在在你说"put in { optional: true } like the error message says"之前......我做到了 - 它摆脱了错误信息,但实际上并没有让动画发挥作用

trigger('listAnimation', [
      transition('* => *', [
        query(':enter', style({ opacity: 0}), { optional: true }),
        query(':enter', stagger('150ms', [
          animate('.5s ease-in', keyframes([
            style({ opacity: 0, /*transform: 'translateY(-75px)',*/ offest: 0}),
            style({ opacity: .5, /*transform: 'translateY(35px)',*/ offest: .3}),
            style({ opacity: 1, /*transform: 'translateY(0px)',*/ offest: 1})
          ]))
        ]), {optional: true})
      ])
    ])

请记住,在从app组件中取出数据之前,这一切都有效。数据就在那里,应用程序正常运行,只是这个动画不再起作用了。

1 个答案:

答案 0 :(得分:0)

您必须确保仅在members数组不为空时才显示列表容器。这样,只有当列表中有内容时,动画才会触发。

ApplicationName