Problem adding eventListener to Google Maps V2 Beta markers

Ionic Framework ionic-v3
1

Here is my code:

for(var i = 0; i < this.events.length; i++)
{
  this.markers.push((this.map.addMarker(
  {
    position: new GoogleMapsLatLng(this.data[i].lat, this.data[i].lng)
  }).then( () => {
    this.markers[i].addEventListener(GoogleMapsEvent.MARKER_CLICK, () => {alert("ok");});
  })));
}

However, nothing happens upon the click. Any idea why?