D3.js Tree Expand All and Collapse All

Question

I\'m building a Tree using D3.js and what I am trying to do is add two buttons, Expand All and Collapse All to the top of the page like this.

Answer 1

try this fiddle: http://jsfiddle.net/z9tmgpwd/

function expand(d) {
var children = (d.children) ? d.children : d._children;
if (d._children) {
    d.children = d._children;
    d._children = null;
}
if (children) children.forEach(expand);
}

function expandAll() {
expand(root);
update(root);
}

function collapseAll() {
root.children.forEach(collapse);
collapse(root);
update(root);
}
var margin = {
    top: 20,
    right: 120,
    bottom: 20,
    left: 120
},
width = 960 - margin.right - margin.left,
height = 800 - margin.top - margin.bottom;
var i = 0,
duration = 750,
root;
var tree = d3.layout.tree().size([height, width]);
var diagonal = d3.svg.diagonal().projection(function (d) {
return [d.y, d.x];
});
var svg = d3.select("body").append("svg").attr("width", width + margin.right 
+ margin.left).attr("height", height + margin.top + 
margin.bottom).append("g").attr("transform", "translate(" + margin.left + 
"," + margin.top + ")");
var flare = {
"name": "flare",
"children": [{
    "name": "analytics",
    "children": [{
        "name": "cluster",
        "children": [{
            "name": "AgglomerativeCluster",
            "size": 3938
        }, {
            "name": "CommunityStructure",
            "size": 3812
        }, {
            "name": "HierarchicalCluster",
            "size": 6714
        }]
    }, {
        "name": "graph",
        "children": [{
            "name": "BetweennessCentrality",
            "size": 3534
        }, {
            "name": "LinkDistance",
            "size": 5731
        }]
    }]
}, {
    "name": "animate",
    "children": [{
        "name": "Easing",
        "size": 17010
    }, {
        "name": "FunctionSequence",
        "size": 5842
    }, {
        "name": "Transitioner",
        "size": 19975
    }, {
        "name": "TransitionEvent",
        "size": 1116
    }, {
        "name": "Tween",
        "size": 6006
    }]
}]
};
root = flare;
root.x0 = height / 2;
root.y0 = 0;

function update(source) {
// Compute the new tree layout.
var nodes = tree.nodes(root).reverse(),
    links = tree.links(nodes);
// Normalize for fixed-depth.
nodes.forEach(function (d) {
    d.y = d.depth * 180;
});
// Update the nodes…
var node = svg.selectAll("g.node").data(nodes, function (d) {
    return d.id || (d.id = ++i);
});
// Enter any new nodes at the parent's previous position.
var nodeEnter = node.enter().append("g").attr("class", 
"node").attr("transform", function (d) {
    return "translate(" + source.y0 + "," + source.x0 + ")";
}).on("click", click).on("mouseover", mouseover).on("mouseout", mouseout);
nodeEnter.append("circle").attr("r", 1e-6).style("fill", function (d) {
    return d._children ? "lightsteelblue" : "#fff";
});
nodeEnter.append("text").attr("x", function (d) {
    return d.children || d._children ? -10 : 10;
}).attr("dy", ".35em").attr("text-anchor", function (d) {
    return d.children || d._children ? "end" : "start";
}).text(function (d) {
    return d.name;
}).style("fill-opacity", 1e-6);
// Transition nodes to their new position.
var nodeUpdate = node.transition().duration(duration).attr("transform", 
function (d) {
    return "translate(" + d.y + "," + d.x + ")";
});
nodeUpdate.select("circle").attr("r", 4.5).style("fill", function (d) {
    return d._children ? "lightsteelblue" : "#fff";
});
nodeUpdate.select("text").style("fill-opacity", 1);
// Transition exiting nodes to the parent's new position.
var nodeExit = node.exit().transition().duration(duration).attr("transform", 
function (d) {
    return "translate(" + source.y + "," + source.x + ")";
}).remove();
nodeExit.select("circle").attr("r", 1e-6);
nodeExit.select("text").style("fill-opacity", 1e-6);
// Update the links…
var link = svg.selectAll("path.link").data(links, function (d) {
    return d.target.id;
});
// Enter any new links at the parent's previous position.
link.enter().insert("path", "g").attr("class", "link").attr("d", function 
(d) {
    var o = {
        x: source.x0,
        y: source.y0
    };
    return diagonal({
        source: o,
        target: o
    });
});
// Transition links to their new position.
link.transition().duration(duration).attr("d", diagonal);
// Transition exiting nodes to the parent's new position.
link.exit().transition().duration(duration).attr("d", function (d) {
    var o = {
        x: source.x,
        y: source.y
    };
    return diagonal({
        source: o,
        target: o
    });
}).remove();
// Stash the old positions for transition.
nodes.forEach(function (d) {
    d.x0 = d.x;
    d.y0 = d.y;
});
}
// Toggle children on click.
function click(d) {
if (d.children) {
    d._children = d.children;
    d.children = null;
} else {
    d.children = d._children;
    d._children = null;
}
update(d);
}

function mouseover(d) {
d3.select(this).append("text").attr("class", "hover").attr('transform', 
function (d) {
    return 'translate(5, -10)';
}).text(d.name + ": " + d.id);
}
// Toggle children on click.
function mouseout(d) {
d3.select(this).select("text.hover").remove();
}

function collapse(d) {
if (d.children) {
    d._children = d.children;
    d._children.forEach(collapse);
    d.children = null;
}
}
update(root);
d3.select(self.frameElement).style("height", "800px");