title: Bind click event listener to map marker (using D3 and JS)
body: <p>I'm following an example on the D3 site to add markers to a Google Map. The example is working, but now I'm trying to bind the click event handler to each marker using the following:</p>
  
  <pre><code>d3.json("stations.json", function(data) {
      var overlay = new google.maps.OverlayView();
  
      // Add the container when the overlay is added to the map.
      overlay.onAdd = function() {
          var layer = d3.select(this.getPanes().overlayLayer).append("div")
          .attr("class", "stations");
  
          // Draw each marker as a separate SVG element.
          // We could use a single SVG, but what size would it have?
          overlay.draw = function() {
          var projection = this.getProjection(),
          padding = 10;
  
          var marker = layer.selectAll("svg")
          .data(d3.entries(data))
          .each(transform) // update existing markers
          .enter().append("svg:svg")
          .each(transform)
          .attr("class", "marker")
          .on("click", function(d) { console.log(d); });
  
          // Add a circle.
          marker.append("svg:circle")
          .attr("r", 4.5)
          .attr("cx", padding)
          .attr("cy", padding);
  
          // Add a label.
          marker.append("svg:text")
          .attr("x", padding + 7)
          .attr("y", padding)
          .attr("dy", ".31em")
          .text(function(d) { return d.key; });
  
          function transform(d) {
              d = new google.maps.LatLng(d.value[1], d.value[0]);
              d = projection.fromLatLngToDivPixel(d);
              return d3.select(this)
              .style("left", (d.x - padding) + "px")
              .style("top", (d.y - padding) + "px");
              }
          };
      };
  
      // Bind our overlay to the map…
      overlay.setMap(map);
  });
  </code></pre>
  
  <p>However, nothing is written to the console when I click any of the markers. Does anyone know where I'm going wrong here?</p>
  
  <p>Thanks</p>