ngFor中的angular2切换图标

Question

有人可以让我知道如何在做ngFor时切换图标吗？

问题陈述:我正在使用*ngFor循环遍历数组并显示类别名称.点击一天,我需要打开一个手风琴并显示类别详细信息(我可以这样做).一旦手风琴打开,我需要用fa-minus替换fa-plus图标,反之亦然,我只需要点击一天即可.

我怎样才能有效实现这一目标？

this.categoryList = [
{type: 'space', name: 'Space'},
{type: 'energy', name: 'Energy'},
{type: 'comfort', name: 'Comfort'},
{type: 'maintenance', name: 'Maintenance'},
{type: 'reporting', name: 'Reporting'}
];

HTML

<div class="{{category.type}}" *ngFor="let category of categoryList">
    <div data-toggle="collapse" [attr.href]="'#'+'category-'+category.type">
    <div class="title {{category.name}}">{{category.name}}</div>
    <div>
        <i class="fa fa-plus"></i> //needs to toggle between plus and minus
                <i class="fa fa-minus"></i> //needs to toggle between plus and minus
    </div>
    </div>

    <div class="collapse" id="category-{{category.type}}">
        //details
    </div>
</div>

Answer 1

如果我理解你,你可以<i>在页面上只有一个而不是两个:

模板:

<div *ngFor="let day of daysInAWeek; let i = index">
    <div>{{day}}</div>
    <div>
        <i class="fa" [ngClass]="toggle[i] ? 'fa-plus': 'fa-minus'" aria-hidden="true"></i>
    </div>
    <div class="details">Today is {{day}}</div>
    <button (click)="toggle[i] = !toggle[i]">Toggle</button>
</div>

TS:

daysInAWeek: string[] = ['Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa', 'Su']; 
toggle = {};

因此,您只需将该元素上的切换类切换为fa-plus或fa-minus

您可以(click)="toggle[i] = !toggle[i]在*ngFortemlpate中放置任何html元素, 以便触发相关<i>元素点击时的切换.