halvorsen
halvorsen

Reputation: 431

How to share HTML between components?

I want to share some HTML (layout) between some of my components but not all.

app.compomonent.html:

<div class="classA">
  <router-outlet></router-outlet>
</div>

Some of my components, but not all, share some HTML:

Component X

<div class="classB">
  <h2>{{Subtitle}}</h2>
</div>
<div class="classC">
  X_SPECIFIC_HTML
</div>

Component Y

<div class="classB">
  <h2>{{Subtitle}}</h2>
</div>
<div class="classC">
  Y_SPECIFIC_HTML
</div>

I want to define the shared HTML (note the data binding) with a placeholder for the actual component HTML:

<div class="classB">
  <h2>{{Subtitle}}</h2>
</div>
<div class="classC">
  INSERT_COMPONENT_HTML_HERE
</div>

So my components can be defined like this:

Component X

X_SPECIFIC_HTML

Component Y

Y_SPECIFIC_HTML

Current routes:

const appRoutes: Routes = [
  { path: 'x', component: XComponent },
  { path: 'y', component: YComponent }
];

Is this possible?

Upvotes: 3

Views: 10621

Answers (1)

halvorsen
halvorsen

Reputation: 431

Got help else where...

Sharing HTML is quite easy using "content projection".

The data binding is a bit more tricky and I managed to do so using a BehaviorSubject.

page-layout.component (the shared HTML)

<div style="background-color: red;">
  <h2>subtitle: {{subtitle}}</h2>
  <ng-content></ng-content>
</div>
import { Component, OnInit } from '@angular/core';
import { LayoutService } from '../../services/layout.service';

@Component({
  selector: 'page-layout',
  templateUrl: './page-layout.component.html',
  styleUrls: ['./page-layout.component.css']
})
export class PageLayoutComponent implements OnInit {

  subtitle = '';

  constructor(private LayoutService: LayoutService) {
  }

  ngOnInit() {
    this.LayoutService.observable.subscribe(x => {
      if (console) {
        console.log('PageLayoutComponent, subscribe: ' + JSON.stringify(x));
      }
      this.subtitle = x.subtitle;
    });
  }
}

assembly-list.component (a component using the shared HTML)

<page-layout>
  <p>ToDo</p>
</page-layout>
import { Component, OnInit } from '@angular/core';
import { LayoutService } from '../../services/layout.service';

@Component({
  selector: 'assembly-list',
  templateUrl: './assembly-list.component.html',
  styleUrls: ['./assembly-list.component.css']
})
export class AssemblyListComponent implements OnInit {

  constructor(private LayoutService: LayoutService) {
  }

  ngOnInit() {
    this.LayoutService.emitTitle(
      'AssemblyListComponent1', 'AssemblyListComponent2'
    );
  }
}

layout-service (the data binding for the shared HTML)

import { Component, Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';

export interface ILayoutServiceData {
  title: string;
  subtitle: string;
}

@Injectable()
export class LayoutService {

  private behaviorSubject: BehaviorSubject<ILayoutServiceData> = 
    new BehaviorSubject({title: null, subtitle: null});

  observable = this.behaviorSubject.asObservable();

  emitTitle(title: string, subtitle: string) {
    if (console) {
      console.log(`LayoutService.emitTitle(\'${title}\', \'${subtitle}\'`);
    }
    const data: ILayoutServiceData = {
      title: title,
      subtitle: subtitle
    };
    this.behaviorSubject.next(data);
  }
}

Upvotes: 5

Related Questions