What is the correct way to select leaf nodes in D3 partition layout example and apply different fill color?

Question

I am using the Zoomable Icicle layout in D3 to visualise a folder hierarchy found here: http://bl.ocks.org/mbostock/1005873 .

At the moment, to fill leaf nodes with a different color I edit the fill of rect:

rect.data(data)
        .enter()
        .append("rect")
        .attr("x", function (d) { return x(d.x); })
        .attr("y", function (d) { return y(d.y); })
        .attr("width", function (d) { return x(d.dx); })
        .attr("height", function (d) { return y(d.dy); })
        .attr("fill", function (d) { return d.children ? /* parent color */ : /* leaf color */; })
.on("click", clicked);

Is this the most correct way to do it?

How can I use a selector to select leaf nodes and apply a different fill color to rect based on the example code?

Thanks!

Answer 1

Yes, this is the correct way to do it -- the only thing that differentiates leaf from non-leaf nodes is whether the children property is null or not.

To select leaf nodes, you can use .selectAll() in conjunction with .filter() :

var leaves = d3.selectAll("rect").filter(function(d) {
  return d.children === null;
});