Lazy Loader for Dialogs

@wizdm/lazy-dialog implements lazy loading for Angular Material Dialogs in the same way the Router does for feature modules.

Installation

Use npm to install the @wizdm/lazy-dialog module:

npm install @wizdm/lazy-dialog

Usage

Import the LazyDialogLoader service and use it as a (CanActivate guard)[https://angular.io/api/router/CanActivate] within the routes you want to associate with your dialogs:

import { LazyDialogLoader } from '@wizdm/lazy-dialog';
...
const routes: Routes = [

  { 
    path: 'home', component: HomeComponent, children: [
      ...
      
      { 
        path: 'login', 
        canActivate: [ LazyDialogLoader ],
        loadChildren: () => import('./login/login.module').then(m => m.LoginModule)
      },

  ]}
...
];

Use login as a regular link in your template:

...
  <a routerLink="login">Login</a>
...

Dialog Module

For the lazily loading to occur, the dialog must be wrapped in a module following the very same pattern of a regular lazily loaded feature module:

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { RouterModule, Routes } from '@angular/router';
import { MatDialogModule } from '@angular/material/dialog';
...
import { LoginComponent } from './login.component';

/** Dialog route. This route will be used by the LazyDialogLoader, emulating the router, to lazily load the dialog */
const routes: Routes = [{
  path: '',
  component: LoginComponent,
  data: { dialogConfig: { width: 350, maxWidth: '100%' }}
}];

@NgModule({

  declarations: [ LoginComponent ],  

  imports: [
    CommonModule,
    MatDialogModule,
    ...,
    RouterModule.forChild(routes)
  ]
})
export class LoginModule { }

Be sure to always include the MatDialogModule within your dialog module since it is crucial for the loader to work properly.

By including a dialogConfig object within the route data, the dialog can be fully configured.

In this example, the LoginComponent implements the dialog following the very same Material Dialog conventions:

import { MAT_DIALOG_DATA, MatDialogRef } from '@angular/material/dialog';
...
@Component({
  selector : 'wm-login-dlg',
  templateUrl : './login.component.html',
  styleUrls : ['./login.component.scss']
})
export class LoginComponent {
  
  constructor(@Inject(MAT_DIALOG_DATA) private data: LoginData, private ref: MatDialogRef<LoginData, User>) {
    ... 
  }

  /** Closes the dialog returning the logged-in user, if any */
  public close(user: User) {
    this.ref.close(user);
  }

Open a dialog programmatically

In the event you need to get access to the returned value from the dialog, you can open the dialog programmatically:

import { LazyDialogLoader } from '@wizdm/lazy-dialog';
...
export class HomeComponent implements OnDestroy {

  constructor(private loader: LazyDialogLoader) { }
  ...
  public login() {

    this.loader.open('login').then( user => {

      console.log('Logged-in', user);

    });
  }
}

Alternatively, you can achieve the same result by using the LazyDialogDirective instead:

  <a openDialog="login" (dialogClosed)="doSomething($event)">Login</a>

How It Works

The LazyDialogLoader works as a CanActivate routing guard preventing the navigation and displaying the dialog instead. The loader seeks for the dialog module within the routes, loads the module, seeks for the dialog component, executes the resolvers, if any, and opens the dialog.