Recreating collapsible force layout using d3 v4

Question

I\'ve been trying to create a Collapsible force layout using d3js v4, similar to this one: https://mbostock.github.io/d3/talk/20111116/force-collapsible.html

I\'ve b

Answer 1

I forgot to merge old nodes after enter().

link = svg.selectAll(".link").data(links, function(d) { return d.target.id; })
var linkEnter = link.enter().append("line").attr("class", "link");
link = linkEnter.merge(link);

Thanks to Mike Bostock for helping me with this problem. I thought there was an issue with d3 v4, turns out I didn't read changes fully :|

Refer this for more info: https://github.com/d3/d3-force/issues/37

Fixed fiddle: https://jsfiddle.net/t4vzg650/6/