Angular 2+ Content Projection and Component property binding

Question

I'm stuck on a hard stuff about Angular Content Projection. I would like to project a component A into another one B and bind some properties on the component A.

For example, I have a SwitchButton component (with several choices). I want this component to display either texts or images.

To do so, here is my SwitchButtonComponent (HTML):

<div class="container border rounded bg-white">
   <div class="row text-center">
      <div *ngFor="let it of items" class="col" style="cursor:pointer;">
         {{it}}
      </div>
   </div>
</div>

I omitted the ts class, no need here, but of course it has an items property. I use this component in another one like so:

<div>
   <switch-button [items]="['A','B','C']"></switch-button>
</div>

Well, this is the easy case. It works fine.

Now, I have a more complex object in items and I want to display an image. It will give:

<div>
   <switch-button [items]="[{path:'./img1.png'},{path:'./img2.png'}]">
       <img-component></img-component>
   </switch-button>
</div>

The img-component is just a simple component rendering an image and having one property: the imgPath.

And in the SwitchButtonComponent:

<div class="container border rounded bg-white">
   <div class="row text-center">
      <div *ngFor="let it of items" class="col" style="cursor:pointer;">
         <ng-content></ng-content>
      </div>
   </div>
</div>

Here you can see I can't bind the imgPath property of the projected component (img-component).

Do you have some ideas guys ?

Ah! Not at all, it's just a mistake of mine! I correct it right now. Thanks :) — Canopy, Oct 18 '18 at 15:14

score -1 · Accepted Answer · answered Oct 18 '18 at 15:50

I don't know if this is possible using ng-content. I solved it using <ng-container> (if that is ok with your requirements):

SwitchButtonComponent:

<div class="container border rounded bg-white">
  <div class="row text-center">
    <div *ngFor="let it of items" class="col" style="cursor:pointer;">
     <ng-container [ngTemplateOutlet]="template" [ngTemplateOutletContext]="{ $implicit: it }"></ng-container>
    </div>
  </div>
</div>

AppComponent:

<div>
  <switch-button [items]="[{path:'./img1.png'},{path:'./img2.png'}]">
    <ng-template let-item>
      <img-component [item]="item"></img-component>
    </ng-template>
  </switch-button>
</div>

ImageComponent:

<div>{{ item.path }}</div>

...

@Input()
item: any;

Here is Stackblitz example demonstrating this.

Hope this helps.

Angular 2+ Content Projection and Component property binding

1 Answers1