d3.js:如何在强制布局中更新链接数据时删除节点

时间:2014-01-12 03:18:13

标签: javascript graph d3.js force-layout

我正在使用强制布局图来显示网络,但在更新数据时遇到问题。

我已经从D3.js检查How to update elements of D3 force layout when the underlying data changes,当然还有“修改力布局”以及“ mbostock ”的“一般更新模式”(不幸的是,我最多只能发布两个链接......)。

我的代码基于“移动专利套装”示例,并有一些修改和差异。 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“更新”按钮后,我想动态更新我的图表。到目前为止一直很好,问题是,只会更新路径但不会更新圆圈或文本(某些圆圈和相应的文本仍然保留,不会被删除),如您所见我的JSFiddle链接。 我试图在过去几天找出问题而没有成功。

我缺少什么,如何让我的代码按预期工作?

如果有人可以提供帮助,我将永远感激。

已修改为@AmeliaBR提供的最终解决方案:

以下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>

1 个答案:

答案 0 :(得分:10)

通用节点链接图结构可以包含没有链接的节点,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那些不再附加任何链接的数据。

他们现在已经设置了它,但是,有一个相当简单的解决方案。您可以从数据集初始化链接,并将节点初始化为空。然后在更新方法的这一部分中:

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,将所有提到的节点作为链接的源或目标添加到节点列表中。

(如果它不在列表中,nodes[link.source]将返回null,因此|| OR运算符将启动并评估语句的后半部分,创建对象,添加它到节点列表,然后将其连接到链接对象。)

现在,第一次运行更新方法时,这会用数据填充节点列表。然而,第二次,节点列表已经满了,你没有做任何事情来取走任何节点。

简单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,只会添加当前链接集中的节点,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,如果你要进行大量更新,并且每次只更改一些对象,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。此版本每次都会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只更改了每个更新,那么为节点对象添加额外的属性可能是值得的,它可以跟踪连接的链接数量,并且只能重置在更新方法开始时。然后,您可以使用过滤器来确定要在数据连接中包含哪些节点对象。

编辑添加:

这是我用于更保守的更新功能的方法(相对于数据的完全重置)。它不是唯一的选择,但它没有太多开销:

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()方法以记录每个节点中的链接数:

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仅包含至少包含一个链接的节点:

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,此nodes列表中删除未使用的节点,它只会过滤它们传递给布局。如果您不希望再次使用这些节点,则需要从节点列表中实际删除它们。

第三步,选项二,扫描节点列表并删除任何零链接的节点:

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*/