Change other HTML elements after clicking on map marker in Mapbox?

Question

This Mapbox tutorial shows how to build a list and have the map pan over to the map marker once the list item had been clicked.

JSFiddle

This is how the a list item handles its click event based on a specific marker:

// Iterate through each feature layer item, build a
// marker menu item and enable a click event that pans to + opens
// a marker that's associated to the marker item.
myLayer.eachLayer(function(marker) {
  var link = info.appendChild(document.createElement('a'));
  link.className = 'item';
  link.href = '#';

  // Populate content from each markers object.
  link.innerHTML = marker.feature.properties.title +
    '<br /><small>' + marker.feature.properties.description + '</small>';
  link.onclick = function() {
    if (/active/.test(this.className)) {
      this.className = this.className.replace(/active/, '').replace(/\s\s*$/, '');
    } else {
      var siblings = info.getElementsByTagName('a');
      for (var i = 0; i < siblings.length; i++) {
        siblings[i].className = siblings[i].className
          .replace(/active/, '').replace(/\s\s*$/, '');
      };
      this.className += ' active';

      // When a menu item is clicked, animate the map to center
      // its associated marker and open its popup.
      map.panTo(marker.getLatLng());
      marker.openPopup();
    }
    return false;
  };
});

How can the reverse be done? Right now if you click directly on a marker, the popup appears but the list items aren't updated to the chosen marker. I'm not quite sure how to bind a click event to the map markers that corresponds to a specific list item.

Answer 1

You would simply need to create a listener attached to the "click" event of your marker, and to keep a reference of your link within the marker.

Then the listener would do the same instructions as the first part of your link.onclick > else block, when it resets the links classes and sets the "active" class on the link of the clicked marker.

Within the anonymous function of myLayer.eachLayer , you could add after the link variable has been assigned:

// Marker click interaction.
marker.on("click", markerClickSetLinkActive);

// Keep a reference to the link within the marker.
marker.link = link;

And somewhere in your script file:

// Marker click interaction function to handle the click event.
function markerClickSetLinkActive(event) {
  var marker = event.target;
  var link = marker.link;

  var siblings = info.getElementsByTagName('a');
  for (var i = 0; i < siblings.length; i++) {
    siblings[i].className = siblings[i].className
      .replace(/active/, '').replace(/\s\s*$/, '');
  };
  link.className += ' active';
}

Demo: http://plnkr.co/edit/oueHiszYQNXEX1oBkXkD?p=preview (using polygons instead of markers, but the process is almost identical).