MarkerClusterer is marker in cluster?

Question

I put markers into clusters:

var markerClusterer = new MarkerClusterer(map, markers, {
    zoomOnClick : false,
    maxZoom : 13,
    gridSize : 100
});

And i have 15 markers. 10 of these are in clusters in the map. How to determine if the marker is in a clusters.

var clusteredMarkers = markerClusterer.getTotalMarkers();
for(i = 0; i < clusteredMarkers.length; i++) {
    if(isInCluster((clusteredMarkers[i])) {
        clusteredMarkers[i].infobox.close();        
    }
}

How to define a function like isInCluster(marker) that infobox is open in only markers, that are not in any cluster (i.e. 5 infoboxes have to be visible)?

Answer 1

The MarkerClusterer will set a marker's map to null if it is in a cluster, so that it is no longer displayed on the map. The MarkerClusterer will then set the marker's map back to map anytime it is no longer in a cluster. You could try checking each of your markers:

var mapOptions = {            // Notice that mapZoom is not set
    center: new google.maps.LatLng( 19, 19 ),
    mapTypeId: google.maps.MapTypeId.ROADMAP };

map = new google.maps.Map( document.getElementById( "map_canvas" ), mapOptions );
var markerClusterer = new MarkerClusterer( map, markers, { ... });

//Whenever the map completes panning or zooming, the function will be called:
google.maps.event.addListener( map, "idle", function() {
    for ( var i = 0; i < markers.length; i++ ) {
        var mrkr = markers[i];
        if ( mrkr.getMap() != null ) {
            mrkr.infobox.open(); 
        }
        else {
            mrkr.infobox.close(); 
        }
    }
}

//Now that map, markerClusterer, and the "idle" event callback are in place,
//set the zoom, which will trigger the "idle" event callback 
//after the zoom activity completes,
map.setZoom( 19 ); //Or whatever is appropriate

//Thereafter, the callback will run after any pan or zoom...

Obviously, the state of the markers is likely to change after a zoom-in, zoom-out, or any other viewport change, so you will have to re-check after viewport changes.