Display clickable list items based on condition in Angular

Question

Let's say I have this list of people I want to display. Below you'll see the HTML for this iteration in a *ngFor loop. You can view this StackBlitz to check out the full example.

<mat-list role="list">
  <mat-list-item *ngFor="let name of names" role="listitem">
    <mat-icon mat-list-icon>person</mat-icon>
    <h4 mat-line>{{name.firstName}}</h4>
  </mat-list-item>
</mat-list>

In some cases the list should be displayed as a linked list, since the list of people then link to other webpages. What I could do to achieve this is to write an *ngIf that checks if it should be a linked list or a normal list, as written below.

<div *ngIf="isNormalList; else isLinkedList">
  <h3>Normal list with items</h3>
  <mat-list role="list">
    <mat-list-item *ngFor="let name of names" role="listitem">
      <mat-icon mat-list-icon>person</mat-icon>
      <h4 mat-line>{{name.firstName}}</h4>
    </mat-list-item>
  </mat-list>
</div>

<ng-template #isLinkedList>
  <h3>List with clickable items</h3>
  <mat-list role="list">
    <a mat-list-item href="#" *ngFor="let name of names" role="listitem">
      <mat-icon mat-list-icon>person</mat-icon>
      <h4 mat-line>{{name.firstName}}</h4>
    </a>
  </mat-list>
</ng-template>

However, solving it this way seems like a lot of duplicate code. I could also write an *ngIf for the inner part of the list item, but that is more or less the same and ends up in duplicate code as well.

Is there a way to only add the a element conditionally within this setup?

Answer 1

Something like this should work. I think you can ease the context bit when using $implicit to make it shorter, but not sure how exactly, you can check the Angular docs.

On a side note, I don't think you need to specify the role attributes, Material should provide these for you.

<div>
  <mat-list role="list">
    <ng-container *ngIf="isNormalList; else isLinkedList">
      <mat-list-item *ngFor="let name of names" role="listitem">
        <ng-container *ngTemplateOutlet="listItem; context: { $implicit: name }"></ng-container>
      </mat-list-item>
    </ng-container>

    <ng-template #isLinkedList>
      <a mat-list-item href="#" *ngFor="let name of names" role="listitem">
        <ng-container *ngTemplateOutlet="listItem; context: { $implicit: name }"></ng-container>
      </a>
    </ng-template>

  </mat-list>
</div>

<ng-template #listItem let-name>
  <mat-icon mat-list-icon>person</mat-icon>
  <h4 mat-line>{{name.firstName}}</h4>
</ng-template>