I'd like to attach a component to a route asynchronously, given a condition.
The following example, which works (but is asynchronous), loads one component or another depending on the user role:
import { UserDashboardComponent } from './user-dashboard.component'
import { AdminDashboardComponent } from './admin-dashboard.component'
const role = 'admin' // Just for the example
const comp = role === 'admin' ? AdminDashboardComponent : UserDashboardComponent
const routes: Routes = [
{ path: '', component: comp },
]
But, let's say we want to retrieve the role from an API, thus asynchronous. What's the way to accomplish that?
You could create a generic.module.ts which will have both components in declarations array:
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { UserDashboardComponent } from './user-dashboard.component'
import { AdminDashboardComponent } from './admin-dashboard.component
@NgModule({
imports: [ BrowserModule ],
declarations: [ UserDashboardComponent,AdminDashboardComponent ]
})
export class GenericModule { }
this way you will have a module that contains the modules which you want to load.
Now next step will be to load them asynchronously using compiler: inside your component do following:
import {GenericModule} from './generic.module';
import { Component, Input,ViewContainerRef, Compiler, NgModule,ModuleWithComponentFactories,OnInit,ViewChild} from '@angular/core';
@Component({
selector: 'generic',
template: '<div #target></div>'
})
export class App implements AfterViewInit {
@ViewChild('target', {read: ViewContainerRef}) target: ViewContainerRef;
constructor(private compiler: Compiler) {}
ngAfterViewInit() {
this.createComponent('<u>Example template...</u>');
}
private createComponent(template: string,role:string) {
@Component({template: template});
const mod = this.compiler.compileModuleAndAllComponentsSync(GenericModule);
const factory = mod.componentFactories.find((comp) =>
//you can add your comparison condition here to load the component
//for eg. comp.selector===role where role='admin'
);
const component = this.target.createComponent(factory);
}
}
Hope this helps.