How to stop renderer keydown event to pass to other components in Angular?

angular hostlistener events
angular hostlistener('keydown)
angular keyboard events
angular 4 keypress event
angular events
hostlistener('focus)
hostlistener input change
hostlistener keyup

I am trying to listen for keydown for particular key in Angular 6. I am able to get the keydown event but it also passes to other services/componenets in my code which are listening for keydown.

I read that this concept is called bubbling and I already tried stopping it but it didn't work.

Below is my implementation:

this.renderer.listen(document, 'keydown', event => { 
      if (event.altkey) { 
            console.log('Alt key pressed');
            event.stopPropagation();
            event.preventDefault();
      } }

I am able to capture 'Alt' key via this code but it is sent to other listeners too.

A listener in the component's decorator is restricted to that component. You might want to replace the listeners in your other components with this.

@Component({
    selector: 'component-selector',
    templateUrl: './component.html',
    styleUrls: ['./component.css'],
    host: {
        "(document:keydown)": "eventHandlingFunction($event)"
    }
})
export class SampleComponent{
    eventHandlingFunction(event:KeyboardEvent){
        //listen and prevent default
    }
}

Listening to Angular Key Events with Host Listeners, I am trying to listen for keydown for particular key in Angular 6. I am able to get the keydown event but it also passes to other services/componenets in my code  When binding to either the keyup or keydown events in your Angular 2+ templates, you can specify key names. This makes it very easy to trigger the event only when specific keys are pressed. This makes it very easy to trigger the event only when specific keys are pressed.

use a HostListener to listen

    @HostListener('keydown', ['$event'])
    open(event: KeyboardEvent) {
         if (event.altkey) { 
            console.log('Alt key pressed');
            event.stopPropagation();
            event.preventDefault();
        }
    }

Optimizing Events handling in Angular, Learn how to listen to keyboard events with Angular and the Host Listener API. With Angular, we try to avoid touching the DOM directly for certain rendering and window and document events like the keyup and keydown events. that we commonly use in our templates to pass back other local events. This works fine but here is a better way in Angular to do the job. Here is how you bind keyup or keydown event to some specific key in Angular.

stopPropagation

will prevent any parent handlers from being executed.

stopImmediatePropagation

will prevent any parent handlers and also any other handlers from executing.

@HostListener('keydown', ['$event'])
open(event: KeyboardEvent) {
     if (event.altkey) { 
        console.log('Alt key pressed');
        // Changed below line of code.
        event.stopImmediatePropagation ();
        event.preventDefault();
      }
}

HostListener, In other words, if we listen to (input) event on an <input> element — we Inside directives and components we can also listen to events on To do so we will wrap handler into an arrow function and pass event with This case could be handled by using @HostListener('keydown.esc.filtered.stop') with a  +1 This would be really great. :) Just enabling\disabling host listeners would already be a great help. There are many cases where I am using the Renderer interface to handle\unhandle DOM events (or acessing the Component events directly) as a work-around, since I can't do this using only the host listeners.

Four ways of listening to DOM events in Angular (Part 1: Event , Decorator that declares a DOM event to listen for, and provides a handler A set of arguments to pass to the handler method when the event occurs. numberOfClicks++); } } @Component({ selector: 'app', template: '<button The following example registers another DOM event handler that listens for key-press events. Using Renderer2 in Angular The Renderer2 class is an abstraction provided by Angular in the form of a service that allows to manipulate elements of your app without having to touch the DOM directly. This is the recommended approach because it then makes it easier to develop apps that can be rendered in environments that don’t have DOM access

Implementing Event Modifiers in Angular, Listening to DOM events and keeping Angular application performant can be challenging. In event binding, information flows from elements in a component If you need access to the event payload object, you can pass $event as a property of keyup or keydown events: keyup.enter or keydown.enter . Binding to user input eventslink. You can use Angular event bindings to respond to any DOM event. Many DOM events are triggered by user input. Binding to these events provides a way to get input from the user. To bind to a DOM event, surround the DOM event name in parentheses and assign a quoted template statement to it.

Event Bubbling and Angular 2, @Output("click.stop") stopPropEvent = new EventEmitter(); We can register a new click event with the help of the Renderer service passing the native element, the event name and Note: You can still pass the $event and any other data to your Different Ways to Pass Inputs to a Component in Angular. In Angular 2 there was a very simple approach using the ComponentResolver but the class is deprecated and will be removed from Angular 2. This blog post will guide you how to use the ComponentFactoryResolver together with NgModule in order to render Angular 2 components dynamically.

Comments
  • you should use the host property in the @Component({..}) for this
  • How is this different that defining the listener inside the componenet directly? Using host will also restrict it to that particular componenet only, isn't it?