How to change the default value of maker cluster for google maps?

Question

I am working in a project on which i use MarkerClustererPlus for Google Maps V3. I've read the documentation but i can't find anywhere how to change the default value that a marker cluster displays(the number of pins in the cluster). I want to change that value with a sum of some values contained in the pins of that cluster. Can this be achieved?

Answer 1

You must set a custom calculator-function.

In this function iterate over all markers, sum what you want to and calculate the index of the style.

Example( will display a sum of a marker-property named prop in the cluster-icon):

markerCluster.setCalculator(function(markers, numStyles) {
  var val=0,//this will be the text you see in the cluster-icon
      index=0,
      dv;

  for(var m=0;m<markers.length;++m){
    //add the value of the markers prop-property to val
    val+=Number(markers[m].prop);
  }
  dv = val;
  while (dv !== 0) {
    dv = parseInt(dv / 10, 10);
    index++;
  }

  index = Math.min(index, numStyles);
  return {
    text: val,
    index: index
  };
}
);