How to use the Angular @HostListener onLoad to get the current width of the viewport?

I’m currently using the Angular @HostListener to get the current width of the viewport onResize() like this:

  @HostListener('window:resize', ['$event'])
  onResize(event?) {
    window.innerWidth <= 400 ? this.width = 200 : this.width = 400;
  }

But I also need a way to set this.width onLoad() of the component (in the constructor or at least in the ngOnInit() lifecycle).

I didn’t found a way to do this with the HostListener. Is there a good alternative to get the current width of the viewport (on resize and on load) and react to it?

My goal is the set the maxWidth of a Leaflet-PopUp on mobile viewport sizes.

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Source Url How to use the Angular @HostListener onLoad to get the current width of the viewport?