Angular: How to pass data in ngComponentOutlet through Injector

Question

I\'m trying to dynamically create and show component and i need to pass some data into it, so that it knows what to show.

Here is my code:

html part:

Answer 1

Hey there change widgets to widgets = [], otherwise angular will keep calling the method in the ngFor loop. If you console log in the constructor for the component you find this is happening.

Answer 2

If you open code of NgComponentOutlet directive:

@Directive({selector: '[ngComponentOutlet]'})
export class NgComponentOutlet implements OnChanges, OnDestroy {
  @Input() ngComponentOutlet: Type<any>;
  @Input() ngComponentOutletInjector: Injector;

you can notice that it takes ngComponentOutlet input that should have type Type<any> but you're passing object to it.

Also we can see that this directive can take Injector as @Input. So lets leverage this knowledge to do your task.

For example we wrote template like:

<ng-container *ngComponentOutlet="component; injector: injector"></ng-container>

Now lets declare component and injector properties in component class:

@Component({...})
export class AppComponent  {

  component: Type<any>;
  injector: Injector;

  constructor(private inj: Injector) {}

  ngOnInit() {
    this.component = ProjectComponent; // note: we're passing type here
    this.injector = Injector.create([
      { provide: BasicProject, useValue: new Project('test name') }
    ], this.inj);
  }
}

and your ProjectComponent now uses angular DI mechanism to get data we passed to injector:

export class ProjectComponent {
  name: string;

  constructor(project: BasicProject) {
    this.name = project.name;
  }
}

Stackblitz Example

Answer 3

Thanks to yuzui's comment I managed to get something working

The full runnable code can be found on Stackblitz

export class AppComponent  {
  name = 'Dynamic components in Angular 5';
  private injectors = {};

  constructor(private inj: Injector) {
  }

  get widgets() {
    return [
      {id: 1, widgetType:'child-component', settings: { showSecondLine: false} },
      {id: 2, widgetType:'child2-component', settings: { text: 'helloooooooooo'} },
      ];
  }
  
  getComponent(config: WidgetConfiguration) {
    switch (config.widgetType) {
      case 'child-component':
        return ChildComponent;
      case 'child2-component':
        return Child2Component;
    }
  }

   getInjector(config: WidgetConfiguration) {
    let inject = this.injectors[config.id];
    if (!inject) {
      inject = Injector.create([
        { provide: GeneralSettings, useValue: config.settings }
      ], this.inj);
      this.injectors[config.id] = inject;
    }

    return inject;
  }
}