heatmap not displaying title on load

[tttp]

Hi,

On the heatmap, the title are empty on load: https://dc-js.github.io/dc.js/examples/heat.html

They are properly generated and displayed when you filter them, but shouldn't the title be displayed at load?

[tttp]

FYI, I "solved" the problem by removing the title and add a tooltip

    var tip = d3.tip()
    .attr('class', 'd3-tip wide-tip')
    .offset([-10, 0])
    .html(function (d) {
      return "<h5>"+d.key+"</h5><div>"
        +d.value
        + "</div>";
    });

    graph.on('pretransition', function() {
      graph.selectAll('.heat-box')
      .call(tip)
      .on('mouseover.tip', tip.show)
      .on('mouseout.tip', tip.hide);
    });

[gordonwoodhull]

Good catch! Thanks @tttp!

[gordonwoodhull]

Looks like this is more fallout of the port to D3v4. The code which sets the titles for both render and redraw is

dc.js/src/heatmap.js

Lines 229 to 234 in 2fa1fca

	if (_chart.renderTitle()) {
	gEnter.append('title');
	boxes.select('title').text(_chart.title());
	}
	boxes = gEnter.merge(boxes);

On the first run, the enter selection is not automatically merged into the update selection as it used to be, so boxes is still empty until the merge in the following line. Moving the merge before the title updates fixes the problem.

I've added a test and a fix for 3.0.7