Latest code attempt:
var node = svg.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", radius - .75)
.style("fill", function(d) { return fill(d.group); })
.style("stroke", function(d) { return d3.rgb(fill(d.group)).darker(); })
.call(force.drag);
var label = svg.selectAll("text")
.data(graph.nodes)
.enter()
.append("text")
.text(function(d){return d.id; });
.style("text-anchor", "middle")
.attr("font-family", "sans-serif")
.attr("font-size", "11px")
.attr("fill", "red");
})
force
.nodes(graph.nodes)
.links(graph.links)
.on("tick", tick)
.start();
function tick() {
node.attr("cx", function(d) { return d.x = Math.max(radius, Math.min(width - radius, d.x)); })
.attr("cy", function(d) { return d.y = Math.max(radius, Math.min(height - radius, d.y)); });
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
label.attr("x", function(d){ return d.x; })
.attr("y", function (d) {return d.y });
Hi Everyone,
I am a newbie to D3 and have spent almost two days on this problem so far to no avail!
I am trying to add node labels to a version of https://bl.ocks.org/mbostock/1129492
I've copy/pasted snippets of code from every forum response I can find and it either breaks my diagram (empty screen on execution) or has no effect (lots of pretty colored circles but no labels). I have been able to add labels to another force diagram successfully but that one was not bounded, and bounding is a key feature I'd like to have. At this stage I have not made any changes to the graph.json file Bostock put up. I am simply trying to get it to display the node text labels.
Can someone please tell me what code I need to write to get labels to show, and where and how to to insert it? I'm determined to not give up on this one!
Here's my code:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
circle {
stroke-width: 1.5px;
}
line {
stroke: #999;
}
text {
font: 12px "open sans";
fill: #fff;
}
</style>
<body>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
var width = 960,
height = 500,
radius = 6;
var fill = d3.scaleOrdinal()
.range(["#a02a65","#2aa02a","#2aa0a0","#a0652a","#a02a2a","#2a2aa0","#65a02a","#a0a02a"])
var simulation = d3.forceSimulation()
.velocityDecay(0.1)
.force("x", d3.forceX(width / 2).strength(.05))
.force("y", d3.forceY(height / 2).strength(.05))
.force("charge", d3.forceManyBody().strength(-240))
.force("link", d3.forceLink().distance(50).strength(1));
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
d3.json("https://[URL HERE]/graph.json", function(error, graph) {
if (error) throw error;
var link = svg.selectAll("line")
.data(graph.links)
.enter().append("line");
var node = svg.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", radius - .75)
.style("fill", function(d) { return fill(d.group); })
.style("stroke", function(d) { return d3.rgb(fill(d.group)).darker(); })
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
var labels = node.append("text")
.text(function(d) {
return d.id;
})
.attr('x', 6)
.attr('y', 3);
node.append("title")
.text(function(d) { return d.id; });simulation
.nodes(graph.nodes)
.on("tick", tick);
simulation.force('link')
.links(graph.links);
function tick() {
node.attr("cx", function(d) { return d.x = Math.max(radius, Math.min(width - radius, d.x)); })
.attr("cy", function(d) { return d.y = Math.max(radius, Math.min(height - radius, d.y)); });
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
}
});
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
</script>
I have modified the example from Mike Bostock to include labels for each node by doing the following:
The label for each node is in graph.nodes so first we create a
selection labels and perform a typical d3 data-join to add text
elements and set the label-text.
The positioning of the labels occurs in the tick() function. On
each step of the animation, we set the x and y attribute of the
text element according to the x and y value of the graph.node
element.
Please note that this example uses d3 v3 so there will be some changes to the syntax - primarily the names used for scale etc. More details can be found here.
I have not attempted to position the text to avoid overlapping. This is reasonably involved and discussed elsewhere like this other SO post.
var width = 960,
height = 500,
radius = 6;
var fill = d3.scale.category20();
var force = d3.layout.force()
.gravity(.05)
.charge(-240)
.linkDistance(50)
.size([width, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
d3.json("https://gist.githubusercontent.com/mbostock/1129492/raw/9513c3fe193673a09e161d49d00a587fd806bdf5/graph.json", function(error, graph) {
if (error) throw error;
var link = svg.selectAll("line")
.data(graph.links)
.enter().append("line");
var node = svg.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", radius - .75)
.style("fill", function(d) { return fill(d.group); })
.style("stroke", function(d) { return d3.rgb(fill(d.group)).darker(); })
.call(force.drag);
var labels = svg.selectAll("text")
.data(graph.nodes)
.enter().append('text')
.text(function (d){return d.name});
force
.nodes(graph.nodes)
.links(graph.links)
.on("tick", tick)
.start();
function tick() {
node.attr("cx", function(d) { return d.x = Math.max(radius, Math.min(width - radius, d.x)); })
.attr("cy", function(d) { return d.y = Math.max(radius, Math.min(height - radius, d.y)); });
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
labels.attr('x', function(d) { return d.x; })
.attr('y', function(d) { return d.y; });
}
});
circle {
stroke-width: 1.5px;
}
line {
stroke: #999;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
Related
I got several nodes and links in place. Unfortunately those are "floating" out of the canvas. I am using D3.V4.js and found several guides how to solve the problem with D3.v3.js. Unfortuantely those doesn´t seem to work. Ideally a hidden or transparent frame would be arranged around the canvas area. I am new building D3 graphs, so I couldn´t figure it out yet.
Maybe you guys could help me to adjust the correct line in my code.
Thanks
var svg = d3.select("svg"),
width = window.innerWidth,
height = +svg.attr("height");
var color = d3.scaleOrdinal(d3.schemeCategory20);
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }).distance(100))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(width / 2, height / 2))
.force("attraceForce",d3.forceManyBody().strength(-2));
var opacity = 0.25;
d3.json("datav2.json", function(error, graph) {
if (error) throw error;
var link = svg.append("g")
.attr("class", "links")
.selectAll("line")
.data(graph.links)
.enter().append("line")
.style("stroke-width", 3)
.style("stroke-linecap", "round")
.attr("linkGroup",function(d) {return d.linkGroup; })
.attr("stroke-width", function(d) { return d.value; })
;
var node = svg.append("g")
.attr("class", "nodes")
.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", 15)
.attr("fill", "#ffffff")
.style("stroke-width", 2)
.style("stroke", function(d) { return color(d.group); })
.attr("nodeGroup",function(d) {return d.nodeGroup; })
.on("click", function(d) {
// This is to toggle visibility - need to do it on the nodes and links
d3.selectAll("line:not([linkGroup='"+d.nodeGroup+"'])")
.style("opacity", function() {
currentDisplay = d3.select(this).style("opacity");
currentDisplay = currentDisplay == "1" ? "0.1" : "1";
return currentDisplay;
});
d3.selectAll("circle:not([nodeGroup='"+d.nodeGroup+"'])")
.style("opacity",function() {
currentDisplay = d3.select(this).style("opacity");
currentDisplay = currentDisplay == "1" ? "0.1" : "1";
return currentDisplay;
});
d3.selectAll("text:not([nodeGroup='"+d.nodeGroup+"'])")
.style("opacity",function() {
currentDisplay = d3.select(this).style("opacity");
currentDisplay = currentDisplay == "1" ? "0.1" : "1";
return currentDisplay;
});
})
.on("mouseover", function(d) {
d3.select(this).style("cursor", "crosshair");
})
.on("mouseout", function(d) {
d3.select(this).style("cursor", "default");
})
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
// This is the label for each node
var text = svg.append("g").selectAll("text")
.data(graph.nodes)
.enter().append("text")
.attr("dy",-25)
.text(function(d) { return d.name;})
.attr("text-anchor", "middle")
.attr("nodeGroup",function(d) {return d.nodeGroup;} ) ;
node.append("title")
.text(function(d) { return d.name; });
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
function neighboring(a, b) {
return graph.links.some(function(d) {
return (d.source.id === a.source.id && d.target.id === b.target.id)
|| (d.source.id === b.source.id && d.target.id === a.target.id);
});
}
function ticked() {
link
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
//.attr("cx2", function(d) { return d.x = Math.max(d.width, Math.min(width - d.width, d.x)); })
//.attr("cy2", function(d) { return d.y = Math.max(d.height, Math.min(height - heightDelta - d.height, d.y)); });
text
.attr("x", function(d) { return d.x; })
.attr("y", function(d) { return d.y; });
}
});
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
Ok I found the issue and added a radius var with a size which fits to the nodes and modified the following line:
node
.attr("cx", function(d) { return d.x = Math.max(radius, Math.min(width - radius, d.x)); })
.attr("cy", function(d) { return d.y = Math.max(radius, Math.min(height - radius, d.y)); })
I am trying to wrap text which is parsed from a json response into my application.
I have two svg elements : rect and text. I want to find a way where I can wrap my svg text such that it fits in the rectangle.
( Picture Force layout with text labels and rectangles )
This is the link to the original project in which I have made modifications
Visualizing Reddit Discussions
setupGraph();
function setupGraph() {
$(".network").empty();
names = {};
nodecolor = {};
force = d3.layout.force()
.charge(-500)
.linkDistance(20)
.size([width, height]);
nodes = force.nodes(),
links = force.links();
force.on("tick", function() {
svg.selectAll("line.link")
.attr("x1", function(d) {
return d.source.x;
})
.attr("y1", function(d) {
return d.source.y;
})
.attr("x2", function(d) {
return d.target.x;
})
.attr("y2", function(d) {
return d.target.y;
});
svg.selectAll("rect.node")
.attr("x", function(d) {
return d.x - d.curWidth / 2;
})
.attr("y", function(d) {
return d.y - d.curHeight / 2;
});
svg.selectAll("text.node")
.attr("x", function(d) {
return d.x - d.curWidth / 2 + 8;
})
.attr("y", function(d) {
return d.y - d.curHeight / 2 + 20;
});
});
d3.select("svg").remove();
svg = d3.select("#chart").append("svg:svg")
.attr("width", width)
.attr("height", height)
.attr("class", "network");
}
function updateNetwork() {
var link = svg.selectAll("line.link")
.data(links, function(d) {
return d.source.id + "-" + d.target.id;
});
link.enter().insert("svg:line", "text.node", "rect.node")
.attr("class", "link")
.style("stroke-width", function(d) {
return 2;
})
.style("stroke", "gray")
.style("opacity", 0.1);
var node = svg.selectAll("rect.node")
.data(nodes, function(d) {
return d.id;
});
var node = svg.selectAll("text.node")
.data(nodes, function(d) {
return d.id;
});
var nodeEnter = node.enter().append("svg:rect")
.attr("class", "node")
.call(force.drag)
.attr("width", function(d) {
return d.curWidth;
})
.attr("height", function(d) {
return d.curHeight;
})
.style("opacity", 1.0)
.on("mouseover", displayTooltip)
.on("mousemove", moveTooltip)
.on("mouseout", removeTooltip)
.on("mouseover", function(d) {
d3.select(this).transition().attr("height", 100).attr("width", 100); //.style("fill", "red");
})
.call(force.drag)
var nodeEnterr = node.enter().append("svg:text")
.attr("class", "node")
.text(function(d) {
return d.name + ": " + d.body
})
.call(force.drag)
.style("opacity", 1.0)
.on("mouseover", displayTooltip)
.on("mousemove", moveTooltip)
.on("mouseout", removeTooltip)
.call(force.drag)
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
I'm able to get images and labels to show for the nodes, but they show at the top left of the screen.
Nodes show up in the correct position when I use this
.enter().append("circle")
Labels and node images show at the top left (incorrect) when I use this:
.enter().append("g")
This works with append "circle" (commented out in the code below):
When I comment out append circle and use append "g" (in order to use node images and labels) the images and labels all show up near (0,0) instead of near the node:
Also, what exactly is append "g"? Where is the documentation to find out what's possible with append "g"?
Here is all the code:
<script>
var width = 960,
height = 500;
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size(\[width, height\]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var graph = getData();
var nodeMap = {};
graph.nodes.forEach(function(d) { nodeMap\[d.name\] = d; });
graph.links.forEach(function(l) {
l.source = nodeMap\[l.source\];
l.target = nodeMap\[l.target\];
})
force.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("stroke", function(d) {
return d.line_color;
})
.style("stroke-width", function(d) {
return Math.sqrt(d.value)+1;
});
var node = svg.selectAll(".node")
.data(graph.nodes)
// .enter().append("circle")
// .attr("class", "node")
// .attr("r", 10)
// .style("fill", function(d) { return d.fill_color; })
// .call(force.drag);
.enter().append("g")
.attr("class", "node")
.attr("r", 15)
.style("fill", function(d) { return d.fill_color; })
.on("click", function(d){
alert("You clicked on node " + d.name);
})
.call(force.drag);
node.append("title")
.text(function(d) { return d.label; });
node.append("image")
.attr("xlink:href", function(d) { return d.image_url })
.attr("x", -8)
.attr("y", -8)
.attr("width", 26)
.attr("height", 26);
node.append("text")
.attr("dx", function(d) {
if (d.image_url == "/profile.png"){
return 100;
}
else{
return 16;
}
})
.attr("dy", function(d) {
if (d.image_url == "/profile.png"){
return 100;
}
else{
return ".35em";
}
})
// .attr("dy", ".35em")
.text(function(d) { return d.name });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
function getData() {
return {
"nodes":\[
{"name":"user1","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"user2","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"user3","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"tag1","image_url":"","fill_color":"blue","text_color":"black"},
{"name":"tag2","image_url":"","fill_color":"blue","text_color":"black"},
{"name":"tag3","image_url":"","fill_color":"blue","text_color":"black"}
\],
"links":\[
{"source":"tag1","target":"user1","value":1,"line_color":"green"},
{"source":"tag2","target":"user1","value":1,"line_color":"green"},
{"source":"tag3","target":"user1","value":1,"line_color":"green"},
{"source":"tag1","target":"user2","value":1,"line_color":"green"},
{"source":"tag2","target":"user2","value":1,"line_color":"green"}
\]
};
}
</script>
With .append("g") you insert a SVG Group Element.
The problem is, that you try to apply attributes that are for circles, like the radius with .attr("r",15), to the group element.
You have to use circles if you want to draw a circle. Group elements do not have any shape. They are used to group elements like circles.
A solution would be to append the g element and transform it to the location of the node. I updated your code in the following snippet. I used the group elements and added the circle, image and text inside the group elements.
Moreover I removed the backslashes before each angular bracket and set the title to the field name instead of label.
var width = 960,
height = 500;
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
var graph = getData();
var nodeMap = {};
graph.nodes.forEach(function(d) { nodeMap[d.name] = d; });
graph.links.forEach(function(l) {
l.source = nodeMap[l.source];
l.target = nodeMap[l.target];
})
force.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll(".link")
.data(graph.links)
.enter()
.append("line")
.attr("class", "link")
.style("stroke", function(d) {
return d.line_color;
})
.style("stroke-width", function(d) {
return Math.sqrt(d.value)+1;
});
var node = svg.selectAll(".node")
.data(graph.nodes)
.enter()
.append("g")
.attr("transform", function(d){return "translate("+d.x+","+d.y+")"})
.call(force.drag);
node.append("circle")
.attr("class", "node")
.attr("r", 15)
.style("fill", function(d) { return d.fill_color; })
.on("click", function(d){
alert("You clicked on node " + d.name);
});
node.append("title")
.text(function(d) { return d.name; });
node.append("image")
.attr("xlink:href", function(d) { return d.image_url })
.attr("x", -8)
.attr("y", -8)
.attr("width", 26)
.attr("height", 26);
node.append("text")
.attr("dx", function(d) {
if (d.image_url == "/profile.png"){
return 100;
}
else{
return 16;
}
})
.attr("dy", function(d) {
if (d.image_url == "/profile.png"){
return 100;
}
else{
return ".35em";
}
})
// .attr("dy", ".35em")
.text(function(d) { return d.name });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("transform", function(d){return "translate("+d.x+","+d.y+")"});
});
function getData() {
return {
"nodes":[
{"name":"user1","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"user2","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"user3","image_url":"http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Wikipedia-logo-v2.svg/103px-Wikipedia-logo-v2.svg.png","fill_color":"blue","text_color":"black"},
{"name":"tag1","image_url":"","fill_color":"blue","text_color":"black"},
{"name":"tag2","image_url":"","fill_color":"blue","text_color":"black"},
{"name":"tag3","image_url":"","fill_color":"blue","text_color":"black"}
],
"links":[
{"source":"tag1","target":"user1","value":1,"line_color":"green"},
{"source":"tag2","target":"user1","value":1,"line_color":"green"},
{"source":"tag3","target":"user1","value":1,"line_color":"green"},
{"source":"tag1","target":"user2","value":1,"line_color":"green"},
{"source":"tag2","target":"user2","value":1,"line_color":"green"}
]
};
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>
I am using D3 api for a graph where a couple of nodes are forming from a parent node i want to color the nodes of the whole graph in a manner that each parent node has a fixed color and the child nodes has different color i.e a root node always have red color and the left child is blue and the right one is green and if only one child is there it is green .I am using this api ,,
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?1.27.1"></script>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.geom.js?1.27.1"></script>
<script type="text/javascript" src="http://mbostock.github.com/d3/d3.layout.js?1.27.1"></script>
<style type="text/css">
line.link {
stroke: #ccc;
}
circle.node {
fill: #000;
stroke: #fff;
stroke-width: 1.5px;
}
</style>
</head>
<body>
<script type="text/javascript">
var w = 960,
h = 500,
r = d3.scale.sqrt().domain([0, 20000]).range([0, 20]);
var force = d3.layout.force()
.gravity(.01)
.charge(-120)
.linkDistance(60)
.size([w, h]);
var svg = d3.select("body").append("svg:svg")
.attr("width", w)
.attr("height", h);
d3.xml("flare.xml", "application/xml", function(xml) {
var nodes = self.nodes = d3.select(xml).selectAll("*")[0],
links = self.links = nodes.slice(1).map(function(d) {
return {source: d, target: d.parentNode};
});
force
.nodes(nodes)
.links(links)
.start();
var link = svg.selectAll("line.link")
.data(links)
.enter().append("svg:line")
.attr("class", "link")
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
var node = svg.selectAll("circle.node")
.data(nodes)
.enter().append("svg:circle")
.attr("class", "node")
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.attr("r", function(d) { return r(d.textContent) || 5; })
.call(force.drag);
force.on("tick", function() {
nodes[0].x = w / 2;
nodes[0].y = h / 2;
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
</script>
</body>
</html>
can anyone help me
SVG has its own CSS properties, one of which being fill. It sets the fill color of an SVG element.
Here is how you use it with D3:
var node = svg.selectAll("circle.node")
.data(nodes)
.enter().append("svg:circle")
.style("fill", function (d) { return '#1f77b4'; })
.attr("class", "node")
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
.attr("r", function(d) { return r(d.textContent) || 5; })
.call(force.drag);
Here the color value (#1f77b4) will be the same for all nodes. If you want to color your nodes with a specific algorithm, D3 ships with predefined categorical color scales.
Edit: Here is a related SO question. One of its answers has a good custom ordinal color scale example.
I still not understanding why the code bellow does not display its labels / text...
I have defined the css and set the attribute like the title when the move is over the node:
Json:
{
"nodes":[
{"name":"t1","group":1},
{"name":"t2","group":1},
{"name":"t3","group":1},
{"name":"t4","group":1},
{"name":"hate","group":2},
{"name":"good","group":2},
{"name":"aiport","group":3},
{"name":"flight","group":3}
],
"links":[
{"source":0,"target":4,"value":4},
{"source":0,"target":5,"value":4},
{"source":1,"target":4,"value":4},
{"source":2,"target":5,"value":4},
{"source":3,"target":5,"value":4},
{"source":4,"target":6,"value":4},
{"source":5,"target":6,"value":4},
{"source":5,"target":7,"value":4}
]
}
Code:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.node {
fill: #555;
stroke: #999;
stroke-width: 1.5px;
}
.link {
stroke: #999;
stroke-opacity: .6;
}
</style>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
var width = 1024,
height = 768;
var color = d3.scale.category20();
var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
d3.json("data.json", function(error, graph) {
force
.nodes(graph.nodes)
.links(graph.links)
.start();
var link = svg.selectAll("line.link")
.data(graph.links)
.enter().append("line")
.attr("class", "link")
.style("stroke-width", function(d) { return Math.sqrt(d.value); });
var node = svg.selectAll("circle.node")
.data(graph.nodes)
.enter().append("circle")
.attr("class", "node")
.attr("r", 5)
.style("fill", function(d) { return color(d.group); })
.call(force.drag);
node.append("title")
.text(function(d) { return d.name; });
node.append("text")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
});
});
</script>
</body>
</html>
You are adding the text element inside the circle element - try running your code and have a look at the svg with the DOM inspector. I'm not sure text is allowed there. Instead add the text elements separately - like another rendering of the nodes:
var texts = svg.selectAll("text.label")
.data(graph.nodes)
.enter().append("text")
.attr("class", "label")
.attr("fill", "black")
.text(function(d) { return d.name; });
force.on("tick", function() {
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
texts.attr("transform", function(d) {
return "translate(" + d.x + "," + d.y + ")";
});
});
Another option would be to add both circle and text elements inside a g container element as shown below:
var container = svg.selectAll("g.node").data(graph.nodes).enter().append("g")
.attr("class", "node")
.attr("transform", function (d) {
return "translate(" + d.x + "," + d.y + ")";
}).call(force.drag);
container.append("circle")
.attr("r", 5)
.style("fill", color);
container.append("text")
.style("text-anchor", "middle")
.text(function (d) {
return d.name;
});
Here you can play with a working jsfiddle:
http://jsfiddle.net/vfu78/16/