NG-bootstrap : open multiple modals in separate components from one click handler

Question

I originally had an ng-bootstrap (5.1.4) modal and the button that opens it inline in my page template, like this:

    <ng-template #basicMessage
                 let-modal>
      <div class="modal-header">
        <h2 id="modal-basic-title"
            class="modal-title">Modal headline</h2>
        <button type="button"
                class="close"
                aria-label="Close"
                (click)="modal.dismiss('Close icon clicked')">
          <span aria-hidden="true"></span>
        </button>
      </div>
      <div class="modal-body">
        <p>Lorem ipsum dolor sit amet, duo ei volumus perfecto ocurreret, nam et volutpat explicari hendrerit.</p>
      </div>
    </ng-template>

    <button class="btn btn-primary mb-3"
            (click)="open(basicMessage, { ariaLabelledBy: 'modal-basic-title' })"
            matRipple>
      View Demo
    </button>

This page has several of these modal demos, each with a different template tag, such as #singleChoiceActionModal and #basicMessage .

Now I would like to move each modal into its own component, and call the modal from the viewdemo button, passing the name of which demo to open. Problem is, once I move the above modal ng-template into its own component:

import { Component } from '@angular/core';

@Component({
  selector: 'app-ngmodal-basic',
  template: `
    <ng-template #basicMessage let-modal>
      <div class="modal-header">
        <h2 id="modal-basic-title" class="modal-title">Modal headline</h2>
        <button type="button" class="close" aria-label="Close" (click)="modal.dismiss('Close icon clicked')">
          <span aria-hidden="true"></span>
        </button>
      </div>
      <div class="modal-body">
        <p>
          Lorem ipsum dolor sit amet, duo ei volumus perfecto ocurreret, nam et volutpat explicari hendrerit.
        </p>
      </div>
    </ng-template>
  `,
  styles: []
})
export class NgmodalBasicComponent {}

and then add this component to my demo page as in

    <app-ngmodal-basic></app-ngmodal-basic>

    <button class="btn btn-primary mb-3"
            (click)="open(basicMessage, { ariaLabelledBy: 'modal-basic-title' })"
            matRipple>
      View Demo
    </button>

the backdrop pops up but no modal.

Since this is a bit confusing, I made a Stackblitz: https://stackblitz.com/edit/angular-rvsxpz

Answer 1

You have to pass Template reference to a first argument of open method. But in your example your are passing undefined that's why It's not working. You have to get app-ngmodal-basic template reference first then pass that ref to open method. To get app-ngmodal-basic template reference use ViewChild, Then add template variable on app-ngmodal-basic to get access

Try this

ng-model-basic.component.ts

export class NgmodalBasicComponent {
  @ViewChild("basicMessage", { static: false })
  public basicMessage: TemplateRef<any>;
  constructor() {}
}

hello.component.html

<app-ngmodal-basic #modal></app-ngmodal-basic>

   <button class="btn btn-primary my-5 d-block"
                (click)="open(modal.basicMessage, { ariaLabelledBy: 'modal-basic-title' })"
                matRipple>
         Open Basic Message Modal
    </button>

Forked Example