Feature: addMarker() now supports custom icons

[Motoma]

Hi there,

I started using your leaflet wrapper and found that I wanted to override the default marker that is created by the addMarker() call. Leaflet already supports this, so I made a minor change to bindings.js to parse out the "icon" option and turn it into an L.Icon.

I'm not a Javascript programmer, but I took a shot at this and it seems to work fine for me.

Cheers,
Chris

[lolokovo]

Hi Chris,

Great job attempting to add this functionality. Thanks very much for that.

I tried to use your solution but was getting an error about the 'in' in the 'if' condition (line 260). This was in Chrome browser. After spending some time modifying the JavaScript I did not succeed to make it working. Even if I succeeded I think your approach would not allow for passing in custom icons through the 'eachOptions' which is something I needed to implement as I need to display various entities on a map with a specific marker icon for each category.

Following implementation of the 'addMarker' method works for 'options' as well as for 'eachOptions':

methods.addMarker = function(lat, lng, layerId, options, eachOptions) {
  var df = dataframe.create()
    .col('lat', lat)
    .col('lng', lng)
    .col('layerId', layerId)
    .cbind(options)
    .cbind(eachOptions);

  for (var i = 0; i < df.nrow(); i++) { 
    (function() {
      var markerOptions = df.get(i);

      try {
          var icon = df.get(i, 'icon');
          icon = L.icon(icon);
          markerOptions.icon = icon;
      }
      catch(err) {}
      finally {
          var marker = L.marker([df.get(i, 'lat'), df.get(i, 'lng')], markerOptions);
          var thisId = df.get(i, 'layerId');
          this.markers.add(marker, thisId);
          marker.on('click', mouseHandler(this.id, thisId, 'marker_click'), this);
          marker.on('mouseover', mouseHandler(this.id, thisId, 'marker_mouseover'), this);
          marker.on('mouseout', mouseHandler(this.id, thisId, 'marker_mouseout'), this);
      }
    }).call(this);
  }
};

Could you please have look at it and let me know if you found any issues with it? I did some basic testing around passing in custom marker icons in various combinations and ways including no custom icon and it seems to be working correctly.

The leaflet-shiny is definitely missing this functionality so whichever solution you find better should get merged to Joe Cheng's master branch.

Your updates in both files were very helpful for me to get this piece working. Thank you again,

Peter