How can I start with all the nodes collapsed in d3js?

Question

从这个示例http://bl.ocks.org/1062288开始，我希望有一个树，所有节点都已折叠，因此初始图应该只包含一个节点（根）。

Answer 1

Option 1: Modify the JSON

Modify the JSON file, readme.json , to use _children instead of children .

Option 2: Edit the Javascript

Edit the javascript to switch the _children and children attributes for every node. This could be done like so

var nodes = flatten(root);
nodes.forEach(function(d) {
  d._children = d.children;
  d.children = null;
});

Here is a JSFiddle for the second option.

Answer 2

var allnode =  flatten(root);
for (var i=0;i<allnode.length;i++){click(allnode[i])}

for those still looking for it, here is 2 lines of code. compact and easy to understand.

Answer 3

Put this here for future readers:

d3.json("json/results.json", function(json) {
    root = json;
    root.x0 = h / 2;
    root.y0 = 0;
    function toggleAll(d) {
    if (d.children) {
      d.children.forEach(toggleAll);
      toggle(d);
    }
}

root.children.forEach(toggleAll);

toggle(root);
update(root);
});

http://jsfiddle.net/chrisloughnane/vV3Sc/