Angular 2.0 and Modal Dialog

Question

• Angular 2 and up
• Bootstrap css (animation is preserved)
• NO JQuery
• NO bootstrap.js
• Supports custom modal content (just like accepted answer)
• Recently added support for multiple modals on top of each other.

`

@Component({
  selector: 'app-component',
  template: `
  <button type="button" (click)="modal.show()">test</button>
  <app-modal #modal>
    <div class="app-modal-header">
      header
    </div>
    <div class="app-modal-body">
      Whatever content you like, form fields, anything
    </div>
    <div class="app-modal-footer">
      <button type="button" class="btn btn-default" (click)="modal.hide()">Close</button>
      <button type="button" class="btn btn-primary">Save changes</button>
    </div>
  </app-modal>
  `
})
export class AppComponent {
}

@Component({
  selector: 'app-modal',
  template: `
  <div (click)="onContainerClicked($event)" class="modal fade" tabindex="-1" [ngClass]="{'in': visibleAnimate}"
       [ngStyle]="{'display': visible ? 'block' : 'none', 'opacity': visibleAnimate ? 1 : 0}">
    <div class="modal-dialog">
      <div class="modal-content">
        <div class="modal-header">
          <ng-content select=".app-modal-header"></ng-content>
        </div>
        <div class="modal-body">
          <ng-content select=".app-modal-body"></ng-content>
        </div>
        <div class="modal-footer">
          <ng-content select=".app-modal-footer"></ng-content>
        </div>
      </div>
    </div>
  </div>
  `
})
export class ModalComponent {

  public visible = false;
  public visibleAnimate = false;

  public show(): void {
    this.visible = true;
    setTimeout(() => this.visibleAnimate = true, 100);
  }

  public hide(): void {
    this.visibleAnimate = false;
    setTimeout(() => this.visible = false, 300);
  }

  public onContainerClicked(event: MouseEvent): void {
    if ((<HTMLElement>event.target).classList.contains('modal')) {
      this.hide();
    }
  }
}

To show the backdrop, you'll need something like this CSS:

.modal {
  background: rgba(0,0,0,0.6);
}

The example now allows for multiple modals at the same time. (see the onContainerClicked() method).

For Bootstrap 4 css users, you need to make 1 minor change (because a css class name was updated from Bootstrap 3). This line: [ngClass]="{'in': visibleAnimate}" should be changed to: [ngClass]="{'show': visibleAnimate}"

To demonstrate, here is a plunkr

Here's a pretty decent example of how you can use the Bootstrap modal within an Angular2 app on GitHub.

The gist of it is that you can wrap the bootstrap html and jquery initialization in a component. I've created a reusable modal component that allows you to trigger an open using a template variable.

<button type="button" class="btn btn-default" (click)="modal.open()">Open me!</button>

<modal #modal>
    <modal-header [show-close]="true">
        <h4 class="modal-title">I'm a modal!</h4>
    </modal-header>
    <modal-body>
        Hello World!
    </modal-body>
    <modal-footer [show-default-buttons]="true"></modal-footer>
</modal>

You just need to install the npm package and register the modal module in your app module:

import { Ng2Bs3ModalModule } from 'ng2-bs3-modal/ng2-bs3-modal';

@NgModule({
    imports: [Ng2Bs3ModalModule]
})
export class MyAppModule {}

This is a simple approach that does not depend on jquery or any other library except Angular 2. The component below (errorMessage.ts) can be used as a child view of any other component. It is simply a bootstrap modal that is always open or shown. It's visibility is governed by the ngIf statement.

errorMessage.ts

import { Component } from '@angular/core';
@Component({
    selector: 'app-error-message',
    templateUrl: './app/common/errorMessage.html',
})
export class ErrorMessage
{
    private ErrorMsg: string;
    public ErrorMessageIsVisible: boolean;

    showErrorMessage(msg: string)
    {
        this.ErrorMsg = msg;
        this.ErrorMessageIsVisible = true;
    }

    hideErrorMsg()
    {
        this.ErrorMessageIsVisible = false;
    }
}

errorMessage.html

<div *ngIf="ErrorMessageIsVisible" class="modal fade show in danger" id="myModal" role="dialog">
    <div class="modal-dialog">

        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal">&times;</button>
                <h4 class="modal-title">Error</h4>
            </div>
            <div class="modal-body">
                <p>{{ErrorMsg}}</p>
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-default" (click)="hideErrorMsg()">Close</button>
            </div>
        </div>
    </div>
</div>

This is an example parent control (some non-relevant code has been omitted for brevity):

parent.ts

import { Component, ViewChild } from '@angular/core';
import { NgForm } from '@angular/common';
import {Router, RouteSegment, OnActivate, ROUTER_DIRECTIVES } from '@angular/router';
import { OnInit } from '@angular/core';
import { Observable } from 'rxjs/Observable';


@Component({
    selector: 'app-application-detail',
    templateUrl: './app/permissions/applicationDetail.html',
    directives: [ROUTER_DIRECTIVES, ErrorMessage]  // Note ErrorMessage is a directive
})
export class ApplicationDetail implements OnActivate
{
    @ViewChild(ErrorMessage) errorMsg: ErrorMessage;  // ErrorMessage is a ViewChild



    // yada yada


    onSubmit()
    {
        let result = this.permissionsService.SaveApplication(this.Application).subscribe(x =>
        {
            x.Error = true;
            x.Message = "This is a dummy error message";

            if (x.Error) {
                this.errorMsg.showErrorMessage(x.Message);
            }
            else {
                this.router.navigate(['/applicationsIndex']);
            }
        });
    }

}

parent.html

<app-error-message></app-error-message>
// your html...

Now available as a NPM package

angular-custom-modal

---

@Stephen Paul continuation...

• Angular 2 and up Bootstrap css (animation is preserved)
• NO JQuery
• NO bootstrap.js
• Supports custom modal content
• Support for multiple modals on top of each other.
• Moduralized
• Disable scroll when modal is open
• Modal gets destroyed when navigating away.
• Lazy content initialization, which gets ngOnDestroy(ed) when the modal is exited.
• Parent scrolling disabled when modal is visible

Lazy content initialization

Why?

In some cases you might not want to modal to retain its status after having been closed, but rather restored to the initial state.

Original modal issue

Passing the content straightforward into the view actually generates initializes it even before the modal gets it. The modal doesn't have a way to kill such content even if using a *ngIf wrapper.

Solution

ng-template. ng-template doesn't render until ordered to do so.

my-component.module.ts

...
imports: [
  ...
  ModalModule
]

my-component.ts

<button (click)="reuseModal.open()">Open</button>
<app-modal #reuseModal>
  <ng-template #header></ng-template>
  <ng-template #body>
    <app-my-body-component>
      <!-- This component will be created only when modal is visible and will be destroyed when it's not. -->
    </app-my-body-content>
    <ng-template #footer></ng-template>
</app-modal>

modal.component.ts

export class ModalComponent ... {
  @ContentChild('header') header: TemplateRef<any>;
  @ContentChild('body') body: TemplateRef<any>;
  @ContentChild('footer') footer: TemplateRef<any>;
 ...
}

modal.component.html

<div ... *ngIf="visible">
  ...
  <div class="modal-body">
    ng-container *ngTemplateOutlet="body"></ng-container>
  </div>

References

I have to say that it wouldn't have been possible without the excellent official and community documentation around the net. It might help some of you too to understand better how ng-template, *ngTemplateOutlet and @ContentChild work.

https://angular.io/api/common/NgTemplateOutlet
https://blog.angular-university.io/angular-ng-template-ng-container-ngtemplateoutlet/
https://medium.com/claritydesignsystem/ng-content-the-hidden-docs-96a29d70d11b
https://netbasal.com/understanding-viewchildren-contentchildren-and-querylist-in-angular-896b0c689f6e
https://netbasal.com/understanding-viewchildren-contentchildren-and-querylist-in-angular-896b0c689f6e

Full copy-paste solution

modal.component.html

<div
  (click)="onContainerClicked($event)"
  class="modal fade"
  tabindex="-1"
  [ngClass]="{'in': visibleAnimate}"
  [ngStyle]="{'display': visible ? 'block' : 'none', 'opacity': visibleAnimate ? 1 : 0}"
  *ngIf="visible">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <ng-container *ngTemplateOutlet="header"></ng-container>
        <button class="close" data-dismiss="modal" type="button" aria-label="Close" (click)="close()">×</button>
      </div>
      <div class="modal-body">
        <ng-container *ngTemplateOutlet="body"></ng-container>
      </div>
      <div class="modal-footer">
        <ng-container *ngTemplateOutlet="footer"></ng-container>
      </div>
    </div>
  </div>
</div>

modal.component.ts

/**
 * @Stephen Paul https://stackoverflow.com/a/40144809/2013580
 * @zurfyx https://stackoverflow.com/a/46949848/2013580
 */
import { Component, OnDestroy, ContentChild, TemplateRef } from '@angular/core';

@Component({
  selector: 'app-modal',
  templateUrl: 'modal.component.html',
  styleUrls: ['modal.component.scss'],
})
export class ModalComponent implements OnDestroy {
  @ContentChild('header') header: TemplateRef<any>;
  @ContentChild('body') body: TemplateRef<any>;
  @ContentChild('footer') footer: TemplateRef<any>;

  public visible = false;
  public visibleAnimate = false;

  ngOnDestroy() {
    // Prevent modal from not executing its closing actions if the user navigated away (for example,
    // through a link).
    this.close();
  }

  open(): void {
    document.body.style.overflow = 'hidden';

    this.visible = true;
    setTimeout(() => this.visibleAnimate = true, 200);
  }

  close(): void {
    document.body.style.overflow = 'auto';

    this.visibleAnimate = false;
    setTimeout(() => this.visible = false, 100);
  }

  onContainerClicked(event: MouseEvent): void {
    if ((<HTMLElement>event.target).classList.contains('modal')) {
      this.close();
    }
  }
}

modal.module.ts

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';

import { ModalComponent } from './modal.component';

@NgModule({
  imports: [
    CommonModule,
  ],
  exports: [ModalComponent],
  declarations: [ModalComponent],
  providers: [],
})
export class ModalModule { }

I use ngx-bootstrap for my project.

You can find the demo here

The github is here

How to use:

1. Install ngx-bootstrap

2. Import to your module

// RECOMMENDED (doesn't work with system.js)
import { ModalModule } from 'ngx-bootstrap/modal';
// or
import { ModalModule } from 'ngx-bootstrap';

@NgModule({
  imports: [ModalModule.forRoot(),...]
})
export class AppModule(){}

3. Simple static modal

<button type="button" class="btn btn-primary" (click)="staticModal.show()">Static modal</button>
<div class="modal fade" bsModal #staticModal="bs-modal" [config]="{backdrop: 'static'}"
tabindex="-1" role="dialog" aria-labelledby="mySmallModalLabel" aria-hidden="true">
<div class="modal-dialog modal-sm">
   <div class="modal-content">
      <div class="modal-header">
         <h4 class="modal-title pull-left">Static modal</h4>
         <button type="button" class="close pull-right" aria-label="Close" (click)="staticModal.hide()">
         <span aria-hidden="true">&times;</span>
         </button>
      </div>
      <div class="modal-body">
         This is static modal, backdrop click will not close it.
         Click <b>&times;</b> to close modal.
      </div>
   </div>
</div>
</div>