marker 除了能群組設定 option 還能監聽事件。

markers.on("click", function (e) {
  // console.log(e.layer);
});

markers.on("clusterclick", function (e) {
  console.log("cluster " + e.layer.getAllChildMarkers().length);
});

markers.on("animationend", (e) => {
  // console.log(e);
});

markers.on("spiderfied", (e) => {
  // console.log(e);
});

markers.on("unspiderfied", (e) => {
  // console.log(e);
});

• clusterclick 事件: 監聽 marker 群組
• animationend :　marker 群組點擊結束動畫後觸發
• spiderfied : marker 群組散開時觸發
• unspiderfied : marker 群組收合後觸發

參考資料:https://github.com/Leaflet/Leaflet.markercluster#events