Angular 6:在ng-container标签内获取使用* ngFor创建的组件的引用 [英] Angular 6: get reference to Components created with *ngFor inside ng-container tag

问题描述

我正在使用ng-container遍历列表并创建组件

I'using ng-container to iterate on a list and create components

    <ng-container *ngFor="let f of optionsList; let i = index;">

                <!-- component-->
                <app-component  #fieldcmp  *ngIf="isAppComponent(f)" ></app-field>


                <!--another components-->
                <app-anoter-component1 *ngIf="isAnotherComponent1(f)"> </app-anoter-component1>
...
                <app-anoter-componentn *ngIf="isAnotherComponentn(f)"> </app-anoter-componentn>

            </ng-container>

我要列出ng-container中的References组件.

I would to list of References components inside ng-container.

我尝试使用@ViewChildren('#fieldcmp')fieldsList:QueryList;和@ContentChildren('#fieldcmp')fieldsList:QueryList;在父组件内部，但是如果尝试在ngafterViewInit中访问，我什么也没得到

I tried to use @ViewChildren('#fieldcmp') fieldsList: QueryList; and @ContentChildren('#fieldcmp') fieldsList: QueryList; inside father component but i get no elements if I try to acces in ngafterViewInit

ngAfterViewInit() {
        this.fieldsList.forEach((child) => {  /* some logic....*/});
    }

有人可以帮助我吗?谢谢

Can someone can help me? Thanks

----------- 更新 -----------------------

-----------Update -----------------------

使用@ViewChildren('fieldcmp')修复后，我有一个 ElementRef 列表，而不是我的AppComponent.我将其全部投放

after fix with @ViewChildren('fieldcmp') I have a list of ElementRef instead of my AppComponent. I cast it with and all work

this.filedsList 
            .forEach((child) => { atLeastOneRequired = atLeastOneRequired || (<ReusableFieldComponent> child).isRequired();
    });

谢谢您的帮助

推荐答案

只需从 ViewChildren 选择器中删除#符号-仅在模板中使用:

Just remove the # sign from your ViewChildren selector - that is used only in templates:

@ViewChildren('fieldcmp') fieldsList: QueryList;

或者您可以使用组件类作为选择器:

Or you could use component class as a selector:

@ViewChildren(HelloComponent) fieldsList: QueryList<HelloComponent>;

在此处工作stackblitz: https://stackblitz.com/edit/angular-xeudlp

Working stackblitz here: https://stackblitz.com/edit/angular-xeudlp

这篇关于Angular 6:在ng-container标签内获取使用* ngFor创建的组件的引用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！