react-google-maps/src/internals/createRegisterEvents.js

React.js Google Maps integration component

function listToMap (map, event_name) {
  map[event_name] = toEventName(event_name);
  return map;
}

function toEventName(name) {
  return `on${ name
    .replace(/^(.)/, groupToUpperCase)
    .replace(/_(.)/g, groupToUpperCase) }`;
}

function groupToUpperCase (match, group) {
  return group.toUpperCase();
}

function createRegisterEvents (event_names) {
  /*
   * list: [click, zoom_changed]
   *  map: (click -> onClick, zoom_changed -> onZoomChanged)
   */
  const list = event_names.split(" ");
  const map = list.reduce(listToMap, {});
  return registerEvents;

 function registerEvents (event, instance, componentProps) {
    var registered = [];
    for (let i = 0; i < list.length; i++) {
      let event_name = list[i];
      let eventName = map[event_name];
      let listener = componentProps[eventName];

      if (listener) {
        registered.push(
          event.addListener(instance, event_name, listener)
        );
      }
    }

    var unregisterEvents = registered.forEach.bind(registered,
      event.removeListener,
      event
    );

    return unregisterEvents;
  }
}

export default createRegisterEvents;