我正在使用力布局图来显示网络，但在更新数据时遇到问题。
我已经检查了 How to update elements of D3 force layout when the underlying data changes ，当然还有来自 D3.js 的“mbostock”的“修改强制布局”和“常规更新模式”(不幸的是，我最多只能发布两个链接...... ).
我的代码基于“移动专利诉讼”示例，并进行了一些修改和差异。 你可以在这里查看我的完整代码:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.link {
fill: none;
stroke: #666;
stroke-width: 1.5px;
}
#licensing {
fill: green;
}
.link.licensing {
stroke: green;
}
.link.resolved {
stroke-dasharray: 0,2 1;
}
circle {
fill: #ccc;
stroke: #333;
stroke-width: 1.5px;
}
text {
font: 10px sans-serif;
pointer-events: none;
text-shadow: 0 1px 0 #fff, 1px 0 0 #fff, 0 -1px 0 #fff, -1px 0 0 #fff;
}
</style>
<body>
<!-- add an update button -->
<div id="update">
<input name="updateButton" type="button" value="Update" onclick="newData()"/>
</div>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
var width = 960,
height = 500;
var force = d3.layout.force()
.size([width, height])
.linkDistance(60)
.charge(-300)
.on("tick", tick);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.style("border", "1px solid black");
var dataset = [
{source: "Microsoft", target: "Amazon", type: "licensing"},
{source: "Microsoft", target: "HTC", type: "licensing"},
{source: "Samsung", target: "Apple", type: "suit"},
{source: "Motorola", target: "Apple", type: "suit"},
{source: "Nokia", target: "Apple", type: "resolved"},
{source: "HTC", target: "Apple", type: "suit"},
{source: "Kodak", target: "Apple", type: "suit"},
{source: "Microsoft", target: "Barnes & Noble", type: "suit"},
{source: "Microsoft", target: "Foxconn", type: "suit"},
{source: "Oracle", target: "Google", type: "suit"},
{source: "Apple", target: "HTC", type: "suit"},
{source: "Microsoft", target: "Inventec", type: "suit"},
{source: "Samsung", target: "Kodak", type: "resolved"},
{source: "LG", target: "Kodak", type: "resolved"},
{source: "RIM", target: "Kodak", type: "suit"},
{source: "Sony", target: "LG", type: "suit"},
{source: "Kodak", target: "LG", type: "resolved"},
{source: "Apple", target: "Nokia", type: "resolved"},
{source: "Qualcomm", target: "Nokia", type: "resolved"},
{source: "Apple", target: "Motorola", type: "suit"},
{source: "Microsoft", target: "Motorola", type: "suit"},
{source: "Motorola", target: "Microsoft", type: "suit"},
{source: "Huawei", target: "ZTE", type: "suit"},
{source: "Ericsson", target: "ZTE", type: "suit"},
{source: "Kodak", target: "Samsung", type: "resolved"},
{source: "Apple", target: "Samsung", type: "suit"},
{source: "Kodak", target: "RIM", type: "suit"},
{source: "Nokia", target: "Qualcomm", type: "suit"}
];
var path = svg.append("g").selectAll("path"),
circle = svg.append("g").selectAll("circle"),
text = svg.append("g").selectAll("text"),
marker = svg.append("defs").selectAll("marker");
var nodes = {};
update(dataset);
function newData()
{
var newDataset = [
{source: "Microsoft", target: "Amazon", type: "licensing"},
{source: "Microsoft", target: "HTC", type: "licensing"},
{source: "Samsung", target: "Apple", type: "suit"},
];
update(newDataset);
}
function update(links)
{
// Compute the distinct nodes from the links.
links.forEach(function(link)
{
link.source = nodes[link.source] || (nodes[link.source] = {name: link.source});
link.target = nodes[link.target] || (nodes[link.target] = {name: link.target});
});
force
.nodes(d3.values(nodes))
.links(links)
.start();
// -------------------------------
// Compute the data join. This returns the update selection.
marker = marker.data(["suit", "licensing", "resolved"]);
// Remove any outgoing/old markers.
marker.exit().remove();
// Compute new attributes for entering and updating markers.
marker.enter().append("marker")
.attr("id", function(d) { return d; })
.attr("viewBox", "0 -5 10 10")
.attr("refX", 15)
.attr("refY", -1.5)
.attr("markerWidth", 6)
.attr("markerHeight", 6)
.attr("orient", "auto")
.append("line") // use ".append("path") for 'arrows'
.attr("d", "M0,-5L10,0L0,5");
// -------------------------------
// Compute the data join. This returns the update selection.
path = path.data(force.links());
// Remove any outgoing/old paths.
path.exit().remove();
// Compute new attributes for entering and updating paths.
path.enter().append("path")
.attr("class", function(d) { return "link " + d.type; })
.attr("marker-end", function(d) { return "url(#" + d.type + ")"; });
// -------------------------------
// Compute the data join. This returns the update selection.
circle = circle.data(force.nodes());
// Add any incoming circles.
circle.enter().append("circle");
// Remove any outgoing/old circles.
circle.exit().remove();
// Compute new attributes for entering and updating circles.
circle
.attr("r", 6)
.call(force.drag);
// -------------------------------
// Compute the data join. This returns the update selection.
text = text.data(force.nodes());
// Add any incoming texts.
text.enter().append("text");
// Remove any outgoing/old texts.
text.exit().remove();
// Compute new attributes for entering and updating texts.
text
.attr("x", 8)
.attr("y", ".31em")
.text(function(d) { return d.name; });
}
// Use elliptical arc path segments to doubly-encode directionality.
function tick()
{
path.attr("d", linkArc);
circle.attr("transform", transform);
text.attr("transform", transform);
}
function linkArc(d)
{
var dx = d.target.x - d.source.x,
dy = d.target.y - d.source.y,
dr = Math.sqrt(dx * dx + dy * dy);
return "M" + d.source.x + "," + d.source.y + "A" + dr + "," + dr + " 0 0,1 " + d.target.x + "," + d.target.y;
}
function transform(d)
{
return "translate(" + d.x + "," + d.y + ")";
}
</script>
我的代码的 JSFiddle 可以在这里找到:http://jsfiddle.net/5m8a9/
按下“更新”按钮后，我想动态更新我的图表。到目前为止一切顺利，问题是，正如您在我的 JSFiddle 链接。 最近几天我试图找出问题所在，但没有成功。
我缺少什么以及如何让我的代码按方面工作？
如果有人能提供帮助，我将不胜感激。
编辑以添加 @AmeliaBR 提供的最终解决方案:
这是我最终解决方案的漏洞代码:
<!DOCTYPE html>
<meta charset="utf-8">
<style>
.link {
fill: none;
stroke: #666;
stroke-width: 1.5px;
}
#licensing {
fill: green;
}
.link.licensing {
stroke: green;
}
.link.resolved {
stroke-dasharray: 0,2 1;
}
circle {
fill: #ccc;
stroke: #333;
stroke-width: 1.5px;
}
text {
font: 10px sans-serif;
pointer-events: none;
text-shadow: 0 1px 0 #fff, 1px 0 0 #fff, 0 -1px 0 #fff, -1px 0 0 #fff;
}
</style>
<body>
<!-- add an update button -->
<div id="update">
<input name="updateButton" type="button" value="Update" onclick="newData()"/>
</div>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
var width = 960,
height = 500;
var force = d3.layout.force()
.size([width, height])
.linkDistance(60)
.charge(-300)
.on("tick", tick);
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.style("border", "1px solid black");
var dataset = [
{source: "Microsoft", target: "Amazon", type: "licensing"},
{source: "Microsoft", target: "HTC", type: "licensing"},
{source: "Samsung", target: "Apple", type: "suit"},
{source: "Motorola", target: "Apple", type: "suit"},
{source: "Nokia", target: "Apple", type: "resolved"},
{source: "HTC", target: "Apple", type: "suit"},
{source: "Kodak", target: "Apple", type: "suit"},
{source: "Microsoft", target: "Barnes & Noble", type: "suit"},
{source: "Microsoft", target: "Foxconn", type: "suit"},
{source: "Oracle", target: "Google", type: "suit"},
{source: "Apple", target: "HTC", type: "suit"},
{source: "Microsoft", target: "Inventec", type: "suit"},
{source: "Samsung", target: "Kodak", type: "resolved"},
{source: "LG", target: "Kodak", type: "resolved"},
{source: "RIM", target: "Kodak", type: "suit"},
{source: "Sony", target: "LG", type: "suit"},
{source: "Kodak", target: "LG", type: "resolved"},
{source: "Apple", target: "Nokia", type: "resolved"},
{source: "Qualcomm", target: "Nokia", type: "resolved"},
{source: "Apple", target: "Motorola", type: "suit"},
{source: "Microsoft", target: "Motorola", type: "suit"},
{source: "Motorola", target: "Microsoft", type: "suit"},
{source: "Huawei", target: "ZTE", type: "suit"},
{source: "Ericsson", target: "ZTE", type: "suit"},
{source: "Kodak", target: "Samsung", type: "resolved"},
{source: "Apple", target: "Samsung", type: "suit"},
{source: "Kodak", target: "RIM", type: "suit"},
{source: "Nokia", target: "Qualcomm", type: "suit"}
];
var path = svg.append("g").selectAll("path"),
circle = svg.append("g").selectAll("circle"),
text = svg.append("g").selectAll("text"),
marker = svg.append("defs").selectAll("marker");
var nodes = {};
update(dataset);
function newData()
{
var newDataset = [
{source: "Microsoft", target: "Amazon", type: "licensing"},
{source: "Microsoft", target: "HTC", type: "licensing"},
{source: "Samsung", target: "Apple", type: "suit"},
];
update(newDataset);
}
function update(links)
{
d3.values(nodes).forEach(function(aNode){ aNode.linkCount = 0;});
// Reset the link count for all existing nodes by
// creating an array out of the nodes list, and then calling a function
// on each node to set the linkCount property to zero.
// Compute the distinct nodes from the links.
links.forEach(function(link)
{
link.source = nodes[link.source] || (nodes[link.source] = {name: link.source, linkCount:0}); // initialize new nodes with zero links
link.source.linkCount++;
// record this link on the source node, whether it was just initialized
// or already in the list, by incrementing the linkCount property
// (remember, link.source is just a reference to the node object in the
// nodes array, when you change its properties you change the node itself.)
link.target = nodes[link.target] || (nodes[link.target] = {name: link.target, linkCount:0}); // initialize new nodes with zero links
link.target.linkCount++;
});
d3.keys(nodes).forEach(
// create an array of all the current keys(names) in the node list,
// and then for each one:
function (nodeKey)
{
if (!nodes[nodeKey].linkCount)
{
// find the node that matches that key, and check it's linkCount value
// if the value is zero (false in Javascript), then the ! (NOT) operator
// will reverse that to make the if-statement return true,
// and the following will execute:
delete(nodes[nodeKey]);
//this deletes the object AND its key from the nodes array
}
}
);
force
.nodes(d3.values(nodes))
.links(links)
.start();
// -------------------------------
// Compute the data join. This returns the update selection.
marker = marker.data(["suit", "licensing", "resolved"]);
// Remove any outgoing/old markers.
marker.exit().remove();
// Compute new attributes for entering and updating markers.
marker.enter().append("marker")
.attr("id", function(d) { return d; })
.attr("viewBox", "0 -5 10 10")
.attr("refX", 15)
.attr("refY", -1.5)
.attr("markerWidth", 6)
.attr("markerHeight", 6)
.attr("orient", "auto")
.append("line") // use ".append("path") for 'arrows'
.attr("d", "M0,-5L10,0L0,5");
// -------------------------------
// Compute the data join. This returns the update selection.
path = path.data(force.links());
// Remove any outgoing/old paths.
path.exit().remove();
// Compute new attributes for entering and updating paths.
path.enter().append("path")
.attr("class", function(d) { return "link " + d.type; })
.attr("marker-end", function(d) { return "url(#" + d.type + ")"; });
// -------------------------------
// Compute the data join. This returns the update selection.
circle = circle.data(force.nodes());
// Add any incoming circles.
circle.enter().append("circle");
// Remove any outgoing/old circles.
circle.exit().remove();
// Compute new attributes for entering and updating circles.
circle
.attr("r", 6)
.call(force.drag);
// -------------------------------
// Compute the data join. This returns the update selection.
text = text.data(force.nodes());
// Add any incoming texts.
text.enter().append("text");
// Remove any outgoing/old texts.
text.exit().remove();
// Compute new attributes for entering and updating texts.
text
.attr("x", 8)
.attr("y", ".31em")
.text(function(d) { return d.name; });
}
// Use elliptical arc path segments to doubly-encode directionality.
function tick()
{
path.attr("d", linkArc);
circle.attr("transform", transform);
text.attr("transform", transform);
}
function linkArc(d)
{
var dx = d.target.x - d.source.x,
dy = d.target.y - d.source.y,
dr = Math.sqrt(dx * dx + dy * dy);
return "M" + d.source.x + "," + d.source.y + "A" + dr + "," + dr + " 0 0,1 " + d.target.x + "," + d.target.y;
}
function transform(d)
{
return "translate(" + d.x + "," + d.y + ")";
}
</script>
最佳答案
一般的节点-链接图结构可以有没有链接的节点，就像它可以有一个、两个或数百个链接的节点一样。您的更新方法会替换链接的数据，但不会查看节点数据以删除不再附加任何链接的节点。
他们目前已经设置好了，但是，有一个相当简单的修复方法。按照原样，您从数据集中初始化链接，并将节点初始化为空。然后在您的更新方法的这一部分:
links.forEach(function(link)
{
link.source = nodes[link.source]
|| (nodes[link.source] = {name: link.source});
link.target = nodes[link.target]
|| (nodes[link.target] = {name: link.target});
});
在首先检查它是否已经在列表中之后，将作为链接的源或目标提到的所有节点添加到节点列表。
(如果它不在列表中，nodes[link.source] 将返回 null，因此 || OR 运算符将启动，下半部分语句的评估，创建对象，将其添加到节点列表，然后将其连接到链接对象。)
现在，第一次运行您的更新方法时，这会用数据填充节点列表。然而，第二次时，节点列表已经满了，您没有做任何事情来移除任何节点。
简单的修复 是在更新方法开始时将节点列表重置为空对象 (nodes={};)。然后，只有当前链接集中的节点才会被添加回来，因此当您重新计算圆圈和文本上的数据连接时，所有未使用的节点将被放入 .exit() 选择并删除。
但是，我应该提一下，如果您要更新很多，并且每次只更改几个对象，还有其他方法可以做到这一点，需要更多代码但更新速度会更快.此版本每次都重新创建所有节点和链接数据对象。如果你有很多(数百个)复杂的数据节点，并且每次更新只改变几个，那么向你的节点对象添加一个额外的属性来跟踪附加了多少链接，并且只重置可能是值得的在您的更新方法开始时。然后您可以使用过滤器来确定哪些节点对象要包含在您的数据连接中。
编辑添加:
这是我用于更保守更新功能的方法(相对于完全重置数据)。这不是唯一的选择，但不会产生太多开销:
第一步(在更新方法中)，将所有节点标记为零链接:
d3.values(nodes).forEach(function(aNode){ aNode.linkCount = 0;});
//Reset the link count for all existing nodes by
//creating an array out of the nodes list, and then calling a function
//on each node to set the linkCount property to zero.
第二步，更改links.forEach()方法，记录每个节点的链接数:
links.forEach(function(link)
{
link.source = nodes[link.source]
|| (nodes[link.source] = {name: link.source, linkCount:0});
//initialize new nodes with zero links
link.source.linkCount++;
// record this link on the source node, whether it was just initialized
// or already in the list, by incrementing the linkCount property
// (remember, link.source is just a reference to the node object in the
// nodes array, when you change its properties you change the node itself.)
link.target = /* and then do the same for the target node */
});
第三步，选项一，使用 filter只包含至少有一个链接的节点:
force
.nodes( d3.values(nodes).filter(function(d){ return d.linkCount;}) )
//Explanation: d3.values() turns the object-list of nodes into an array.
//.filter() goes through that array and creates a new array consisting of
//the nodes that return TRUE when passed to the callback function.
//The function just returns the linkCount of that node, which Javascript
//interprets as false if linkCount is zero, or true otherwise.
.links(links)
.start();
请注意，这不会从nodes 列表中删除未使用的节点，它只会过滤掉它们以防止传递到布局。如果您不希望再次使用这些节点，则需要实际将它们从节点列表中删除。
第三步，选项二，扫描节点列表并删除所有具有零链接的节点:
d3.keys(nodes).forEach(
//create an array of all the current keys(names) in the node list,
//and then for each one:
function (nodeKey) {
if (!nodes[nodeKey].linkCount) {
// find the node that matches that key, and check it's linkCount value
// if the value is zero (false in Javascript), then the ! (NOT) operator
// will reverse that to make the if-statement return true,
// and the following will execute:
delete(nodes[nodeKey]);
//this deletes the object AND its key from the nodes array
}
}//end of function
); //end of forEach method
/*then add the nodes list to the force layout object as before,
no filter needed since the list only includes the nodes you want*/
关于javascript - d3.js:如何在强制布局中更新链接数据时删除节点，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21070899/