I want to create a service which detects all keyboard input, translates the key strokes into actions based on a configurable mapping, and exposes observables which various elements can bind to to react to specific key presses.
The following is a simplification of my code so far, it worked when HostListener was in a component, but now I've moved it into a service it never fires even though it is definitely initialised. Is it not possible to detect input like this in a service?
import { Injectable, HostListener } from '@angular/core';
import { Subject } from 'rxjs/Subject';
@Injectable()
export class InputService {
@HostListener('window:keydown', ['$event'])
keyboardInput(event: any) {
console.log(event);
}
}
Seems like its not possible to use HostListener
in a service.
UPDATE
like Stanislasdrg Reinstate Monica
wrote, there's a more elegant and more angular way using the renderer..
@Injectable()
export class MyMouseService implements OnDestroy {
private _destroy$ = new Subject();
public onClick$: Observable<Event>;
constructor(private rendererFactory2: RendererFactory2) {
const renderer = this.rendererFactory2.createRenderer(null, null);
this.createOnClickObservable(renderer);
}
ngOnDestroy() {
this._destroy$.next();
this._destroy$.complete();
}
private createOnClickObservable(renderer: Renderer2) {
let removeClickEventListener: () => void;
const createClickEventListener = (
handler: (e: Event) => boolean | void
) => {
removeClickEventListener = renderer.listen("document", "click", handler);
};
this.onClick$ = fromEventPattern<Event>(createClickEventListener, () =>
removeClickEventListener()
).pipe(takeUntil(this._destroy$));
}
}
live-demo: https://stackblitz.com/edit/angular-so4?file=src%2Fapp%2Fmy-mouse.service.ts
OLD
You could use the old way window.addEventListener
like @yurzui pointed out already.
https://plnkr.co/edit/tc53cvQDfLHhaR68ilKr?p=preview
import {Component, NgModule, HostListener, Injectable} from '@angular/core'
import {BrowserModule} from '@angular/platform-browser'
@Injectable()
export class MyService {
constructor() {
window.addEventListener('keydown', (event) => {
console.dir(event);
});
}
}
@Component({
selector: 'my-app',
template: `
<div>
<h2>Hello {{name}}</h2>
</div>
`,
})
export class App {
constructor(private _srvc: MyService) {
this.name = 'Angular2'
}
}
@NgModule({
imports: [ BrowserModule ],
declarations: [ App ],
providers: [MyService],
bootstrap: [ App ]
})
export class AppModule {}