How I can call showinfowindow() in a marker within cluster manager?

Question

I'm working with markers in a cluster (google maps), I have no problem in showing an info window when calling the onclick method. The problem is that I can't find how to use the method showInfoWindow() as I do on a marker to open the info without giving click.

When I use a marker

marker = map.addMarker(new MarkerOptions()
                    .position(position)
                    .snippet(info));

then I call

marker.showInfoWindow();

how I can do the same with a marker (ClusterItem) that is on the map within the cluster manager?

MarkCluster cluster = new MarkCluster(Lat, Lon, info);
mClusterManager.addItem(cluster);

It is the marker that I want to show infoWindow

Answer 1

Try this, its what I did to get references to map markers when using clustering:

When you create a ClusterManager it always creates and uses an instance of the DefaultClusterRenderer if you don't call the .setRenderer() method and pass it an instance of your own ClusterRenderer implementation. If you are letting the ClusterManager create its own DefaultClusterRenderer the key is to add it explicitly so that you can keep a reference to it (because the ClusterManager has no getter method so you can get a reference to the ClusterRenderer its using):

mClusterManager = new ClusterManager<ClusterItem>(getActivity(), mMap);
mRenderer = new DefaultClusterRenderer(getActivity(), mMap, mClusterManager); 
mClusterManager.setRenderer(mRenderer); 
mClusterManager.addItem(ClusterItem);  

Then when you need access to a marker pass the ClusterRenderer the ClusterItem associated with the marker. The ClusterItem you use to find the marker will be the ClusterItem you passed to the ClusterManager to add the marker to the cluster originally:

Marker marker = mRenderer.getMarker(ClusterItem);
if(marker != null){
    marker.showInfoWindow();
}

The Marker object will be null if the marker has not been rendered on the map yet so be sure to check that the marker object is not null before using it.

If you are certain the marker has been placed on the map when you call .getMarker() and marker is still null then override the .equals() method in the object use to implement the ClusterItem Interface to make sure you can find the correct ClusterItem object held by the renderer.