Question

I want to alert the user about new position on map when he/she dragged the marker. Apparently when I drag my marker, the listener even will not trigger. I want my user be able to choose to put marker on map and also be able to drag it. clicking and dragging other side of the map can change the marker position, but when I try to add the listener for dragging the map, to pop up a menu alert, it doesn’t work. Thanks

var LatLng = new google.maps.LatLng(lat,lng);
        var marker;
        var mapOptions = {
          center: LatLng,
          zoom: 16,
          minZoom:12,
          maxZoom:18,
          panControl:false,
          scrollwheel: false,
          rotateControl:false,
          streetViewControl:false,
          keyboardShortcuts:false,
          mapTypeControl: false,
          scaleControl: false,
          mapTypeId: google.maps.MapTypeId.ROADMAP
        };


        var Gmap = new google.maps.Map($('#map_canvas').get(0),mapOptions);


        // adding pointer by clicking on mac
        google.maps.event.addListener(Gmap, 'click', function(e) {
            if (marker) {
                marker.setPosition(e.latLng);
            }else{
                marker = new google.maps.Marker({
                    position: e.latLng,
                    map: Gmap,
                    draggable:true
                });
            }

              Gmap.panTo(marker.getPosition());


        });

         google.maps.event.addListener(marker, 'dragend', function() {
             alert('Show something here');
        });

Answer 1

The listener isn’t working because when you define your listener, the marker is undefined. You need to place it in the function block that defines your marker:

google.maps.event.addListener(Gmap, 'click', function(e) {
    if (marker) {
        marker.setPosition(e.latLng);
    } else {
        marker = new google.maps.Marker({
            position: e.latLng,
            map: Gmap,
            draggable:true
        });

        google.maps.event.addListener(marker, 'dragend', function() {
             alert('Show something here');
        });
    }

    Gmap.panTo(marker.getPosition());
});

See that in action right here.