javascript - D3 V4：更新的数据被视为新数据？（更新功能）

Question

目前，我正在构建一个系统，但更新功能遇到了一些问题。

本质上，我正在尝试将新节点添加到 D3 树中。当用户单击节点的“添加按钮”时，可以添加新的子节点。每个添加按钮都可以在每个节点的左侧找到。

我遵循了 Mike Bostock 的一般更新模式。单击按钮后，唯一的“新”数据元素应该是新创建的子节点，但看起来整个数据都被视为“新”。当我查看每个节点的类名以及所有节点到达中心节点并消失的明显事实时，我得出了这个结论。其他原始数据应该“更新”，但事实并非如此。谁能温和地指出为什么会这样？

我的代码的工作示例可以在这个jfiddle 链接中找到。

编辑 06/09

鉴于 Gordon 的建议，我为我的节点和链接都找到了一个独特的字段。因此，为了唯一标识数据，我进行了以下更改：

节点

.data(d, d => d.data.name)

关联

.data(d, d => d.source.data.name)

这种变化（大部分）有效，但我看到一些奇怪的行为仍在发生：（1）分支 7.2.1 仍然被识别为一个新节点并消失；(2) 在第二次“添加”左右之后，链接没有与其各自的节点正确对齐。我认为我的两个小编辑正在影响这一点，因为当我回到原始代码时，线条被正确绘制，尽管它们正在过渡。想法？建议？

---

HTML

  <div id="div-mindMap">

CSS

.linkMindMap {
    fill: none;
    stroke: #555;
    stroke-opacity: 0.4;
}    
rect {
    fill: white;
    stroke: #3182bd;
    stroke-width: 1.5px;  
 }

JS

const widthMindMap = 700;
const heightMindMap = 700;
let parsedData;

let parsedList = {
  "name": " Stapler",
  "children": [{
      "name": " Bind",
      "children": []
    },
    {
      "name": "   Nail",
      "children": []
    },
    {
      "name": "   String",
      "children": []
    },
    {
      "name": " Glue",
      "children": [{
          "name": "Gum",
          "children": []
        },
        {
          "name": "Sticky Gum",
          "children": []
        }
      ]
    },
    {
      "name": " Branch 3",
      "children": []
    },
    {
      "name": " Branch 4",
      "children": [{
          "name": "   Branch 4.1",
          "children": []
        },
        {
          "name": "   Branch 4.2",
          "children": []
        },
        {
          "name": "   Branch 4.1",
          "children": []
        }
      ]
    },
    {
      "name": " Branch 5",
      "children": []
    },
    {
      "name": " Branch 6",
      "children": []
    },
    {
      "name": " Branch 7",
      "children": []
    },
    {
      "name": "   Branch 7.1",
      "children": []
    },
    {
      "name": "   Branch 7.2",
      "children": [{
          "name": "   Branch 7.2.1",
          "children": []
        },
        {
          "name": "   Branch 7.2.1",
          "children": []
        }
      ]
    }
  ]
}


let svgMindMap = d3.select('#div-mindMap')
  .append("svg")
  .attr("id", "svg-mindMap")
  .attr("width", widthMindMap)
  .attr("height", heightMindMap);


let backgroundLayer = svgMindMap.append('g')
  .attr("width", widthMindMap)
  .attr("height", heightMindMap)
  .attr("class", "background")

let gLeft = backgroundLayer.append("g")
  .attr("transform", "translate(" + widthMindMap / 2 + ",0)")
  .attr("class", "g-left");
let gLeftLink = gLeft.append('g')
  .attr('class', 'g-left-link');
let gLeftNode = gLeft.append('g')
  .attr('class', 'g-left-node');


function loadMindMap(parsed) {
  var data = parsed;
  var split_index = Math.round(data.children.length / 2);

  parsedData = {
    "name": data.name,
    "children": JSON.parse(JSON.stringify(data.children.slice(split_index)))
  };

  var left = d3.hierarchy(parsedData, d => d.children);

  drawLeft(left, "left");
}

// draw single tree
function drawLeft(root, pos) {
  var SWITCH_CONST = 1;
  if (pos === "left") SWITCH_CONST = -1;

  update(root, SWITCH_CONST);
}

function update(source, SWITCH_CONST) {
  var tree = d3.tree()
    .size([heightMindMap, SWITCH_CONST * (widthMindMap - 150) / 2]);
  var root = tree(source);

  console.log(root)

  var nodes = root.descendants();
  var links = root.links();

  console.log(nodes)
  console.log(links)
  // Set both root nodes to be dead center vertically
  nodes[0].x = heightMindMap / 2

  //JOIN new data with old elements
  var link = gLeftLink.selectAll(".link-left")
    .data(links, d => d)
    .style('stroke-width', 1.5);

  var linkEnter = link.enter().append("path")
    .attr("class", "linkMindMap link-left")
    .attr("d", d3.linkHorizontal()
      .x(d => d.y)
      .y(d => d.x));

  var linkUpdate = linkEnter.merge(link);

  linkUpdate.transition()
    .duration(750)
  var linkExit = link.exit()
    .transition()
    .duration(750)
    .attr('x1', function(d) {
      return root.x;
    })
    .attr('y1', function(d) {
      return root.y;
    })
    .attr('x2', function(d) {
      return root.x;
    })
    .attr('y2', function(d) {
      return root.y;
    })
    .remove();

  //JOIN new data with old elements
  var node = gLeftNode.selectAll(".nodeMindMap-left")
    .data(nodes, d => d);

  console.log(nodes);


  //ENTER new elements present in new data
  var nodeEnter = node.enter().append("g").merge(node)
    .attr("class", function(d) {
      return "nodeMindMap-left " + "nodeMindMap" + (d.children ? " node--internal" : " node--leaf");
    })
    .classed("enter", true)
    .attr("transform", function(d) {
      return "translate(" + d.y + "," + d.x + ")";
    })
    .attr("id", function(d) {
      let str = d.data.name;
      str = str.replace(/\s/g, '');
      return str;
    });

  nodeEnter.append("circle")
    .attr("r", function(d, i) {
      return 2.5
    });

  var addLeftChild = nodeEnter.append("g")
    .attr("class", "addHandler")
    .attr("id", d => {
      let str = d.data.name;
      str = "addHandler-" + str.replace(/\s/g, '');
      return str;
    })
    .style("opacity", "1")
    .on("click", (d, i, nodes) => addNewLeftChild(d, i, nodes));

  addLeftChild.append("line")
    .attr("x1", -74)
    .attr("y1", 1)
    .attr("x2", -50)
    .attr("y2", 1)
    .attr("stroke", "#85e0e0")
    .style("stroke-width", "2");

  addLeftChild.append("rect")
    .attr("x", "-77")
    .attr("y", "-7")
    .attr("height", 15)
    .attr("width", 15)
    .attr("rx", 5)
    .attr("ry", 5)
    .style("stroke", "#444")
    .style("stroke-width", "1")
    .style("fill", "#ccc");

  addLeftChild.append("line")
    .attr("x1", -74)
    .attr("y1", 1)
    .attr("x2", -65)
    .attr("y2", 1)
    .attr("stroke", "#444")
    .style("stroke-width", "1.5");

  addLeftChild.append("line")
    .attr("x1", -69.5)
    .attr("y1", -3)
    .attr("x2", -69.5)
    .attr("y2", 5)
    .attr("stroke", "#444")
    .style("stroke-width", "1.5");

  // .call(d3.drag().on("drag", dragged));;

  nodeEnter.append("foreignObject")
    .style("fill", "blue")
    .attr("x", -50)
    .attr("y", -7)
    .attr("height", "20px")
    .attr("width", "100px")
    .append('xhtml:div')
    .append('div')
    .attr("class", 'clickable-node')
    .attr("id", function(d) {
      let str = d.data.name;
      str = "div-" + str.replace(/\s/g, '');
      return str;
    })
    .attr("ondblclick", "this.contentEditable=true")
    .attr("onblur", "this.contentEditable=false")
    .attr("contentEditable", "false")
    .style("text-align", "center")
    .text(d => d.data.name);

  //TODO: make it dynamic
  nodeEnter.insert("rect", "foreignObject")
    .attr("ry", 6)
    .attr("rx", 6)
    .attr("y", -10)
    .attr("height", 20)
    .attr("width", 100)
    // .filter(function(d) { return d.flipped; })
    .attr("x", -50)
    .classed("selected", false)
    .attr("id", function(d) {
      let str = d.data.name;
      str = "rect-" + str.replace(/\s/g, '');
      return str;
    });

  var nodeUpdate = nodeEnter.merge(node);
  // Transition to the proper position for the node
  nodeUpdate.transition()
    .duration(750)
    .attr("transform", function(d) {
      return "translate(" + d.y + "," + d.x + ")";
    });

  // Remove any exiting nodes
  var nodeExit = node.exit()
    .transition()
    .duration(750)
    .attr("transform", function(d) {
      return "translate(" + source.y + "," + source.x + ")";
    })
    .remove();

  // On exit reduce the node circles size to 0
  nodeExit.select('circle').attr('r', 0);
  // node = nodeEnter.merge(node)
}

function addNewLeftChild(d, i, nodes) {
  console.log("make new child");
  event.stopPropagation();
  var newNodeObj = {
    // name: new Date().getTime(),
    name: "New Child",
    children: []
  };

  console.log("this is ", parsedData)
  //Creates new Node
  var newNode = d3.hierarchy(newNodeObj);
  newNode.depth = d.depth + 1;
  newNode.height = d.height - 1;
  newNode.parent = d;
  newNode.id = Date.now();

  console.log(newNode);
  console.log(d)

  if (d.data.children.length == 0) {
    console.log("i have no children")
    d.children = []
  }
  d.children.push(newNode)
  d.data.children.push(newNode.data)

  console.log(d)
  let foo = d3.hierarchy(parsedData, d => d.children) 
  drawLeft(foo, "left");
}


loadMindMap(parsedList);

标签： javascripthtmld3.jsupdates

Answer 1

有几件事正在发生：

使用唯一键

使用名称并不是键的最佳选择，因为每个新节点都有相同的名称（“新子节点”）。相反，使用某种 ID 系统可能会更好。这是一个用 ID 标记每个节点的数据的快速函数。

let currNodeId = 0;
function idData(node) {
  node.nodeId = ++currNodeId;
  node.children.forEach(idData);
}
idData(parsedList);

而且由于您要重新定义 中的数据parsedData，因此您也需要在其中使用 id 属性：

  parsedData = {
    "name": data.name,
    "nodeId": data.nodeId,
    "children": JSON.parse(JSON.stringify(data.children.slice(split_index)))
  };

添加新节点时，也可以在nodeData中设置：

  var newNodeObj = {
    // name: new Date().getTime(),
    name: "New Child",
    nodeId: ++currNodeId,
    children: []
  };

然后实际.nodeId用作节点的键，将其用作键函数：

    .data(nodes, d => d.data.nodeId);

对于链接，您应该使用target代替source，因为这是一棵树，每个子节点只有一个链接（而不是一个父节点的多个链接）。

    .data(nodes, d => d.target.data.nodeId);

防止添加多个节点元素

还有一个问题是在添加新元素之前合并新旧节点。为了防止这种情况，你应该改变

node.enter().append("g").merge(node)

到：

node.enter().append("g")

链接转换

最后，您的链接的转换不会与节点一起转换。要使它们过渡，请移动：

    .attr("d", d3.linkHorizontal()
      .x(d => d.y)
      .y(d => d.x));

低于

  linkUpdate.transition()
    .duration(750)

总而言之，它看起来像这样：https ://jsfiddle.net/v9wyb6q4/

或者：

const widthMindMap = 700;
const heightMindMap = 700;
let parsedData;

let parsedList = {
  "name": " Stapler",
  "children": [{
      "name": " Bind",
      "children": []
    },
    {
      "name": "   Nail",
      "children": []
    },
    {
      "name": "   String",
      "children": []
    },
    {
      "name": " Glue",
      "children": [{
          "name": "Gum",
          "children": []
        },
        {
          "name": "Sticky Gum",
          "children": []
        }
      ]
    },
    {
      "name": " Branch 3",
      "children": []
    },
    {
      "name": " Branch 4",
      "children": [{
          "name": "   Branch 4.1",
          "children": []
        },
        {
          "name": "   Branch 4.2",
          "children": []
        },
        {
          "name": "   Branch 4.1",
          "children": []
        }
      ]
    },
    {
      "name": " Branch 5",
      "children": []
    },
    {
      "name": " Branch 6",
      "children": []
    },
    {
      "name": " Branch 7",
      "children": []
    },
    {
      "name": "   Branch 7.1",
      "children": []
    },
    {
      "name": "   Branch 7.2",
      "children": [{
          "name": "   Branch 7.2.1",
          "children": []
        },
        {
          "name": "   Branch 7.2.1",
          "children": []
        }
      ]
    }
  ]
}
let currNodeId = 0;
function idData(node) {
	node.nodeId = ++currNodeId;
  node.children.forEach(idData);
}
idData(parsedList);

let svgMindMap = d3.select('#div-mindMap')
  .append("svg")
  .attr("id", "svg-mindMap")
  .attr("width", widthMindMap)
  .attr("height", heightMindMap);


let backgroundLayer = svgMindMap.append('g')
  .attr("width", widthMindMap)
  .attr("height", heightMindMap)
  .attr("class", "background")

let gLeft = backgroundLayer.append("g")
  .attr("transform", "translate(" + widthMindMap / 2 + ",0)")
  .attr("class", "g-left");
let gLeftLink = gLeft.append('g')
  .attr('class', 'g-left-link');
let gLeftNode = gLeft.append('g')
  .attr('class', 'g-left-node');


function loadMindMap(parsed) {
  var data = parsed;
  var split_index = Math.round(data.children.length / 2);

  parsedData = {
    "name": data.name,
    "nodeId": data.nodeId,
    "children": JSON.parse(JSON.stringify(data.children.slice(split_index)))
  };

  var left = d3.hierarchy(parsedData, d => d.children);

  drawLeft(left, "left");
}

// draw single tree
function drawLeft(root, pos) {
  var SWITCH_CONST = 1;
  if (pos === "left") SWITCH_CONST = -1;

  update(root, SWITCH_CONST);
}

function update(source, SWITCH_CONST) {
  var tree = d3.tree()
    .size([heightMindMap, SWITCH_CONST * (widthMindMap - 150) / 2]);
  var root = tree(source);

  console.log(root)

  var nodes = root.descendants();
  var links = root.links();

  console.log(nodes)
  console.log(links)
  // Set both root nodes to be dead center vertically
  nodes[0].x = heightMindMap / 2

  //JOIN new data with old elements
  var link = gLeftLink.selectAll(".link-left")
    .data(links, d => d.target.data.nodeId)
    .style('stroke-width', 1.5);

  var linkEnter = link.enter().append("path")
    .attr("class", "linkMindMap link-left");

  var linkUpdate = linkEnter.merge(link);

  linkUpdate.transition()
    .duration(750)
    .attr("d", d3.linkHorizontal()
      .x(d => d.y)
      .y(d => d.x));
  var linkExit = link.exit()
    .transition()
    .duration(750)
    .attr('x1', function(d) {
      return root.x;
    })
    .attr('y1', function(d) {
      return root.y;
    })
    .attr('x2', function(d) {
      return root.x;
    })
    .attr('y2', function(d) {
      return root.y;
    })
    .remove();

  //JOIN new data with old elements
  var node = gLeftNode.selectAll(".nodeMindMap-left")
    .data(nodes, d => d.data.nodeId);

  console.log(nodes);

  
  //ENTER new elements present in new data
  var nodeEnter = node.enter().append("g")
    .attr("class", function(d) {
      return "nodeMindMap-left " + "nodeMindMap" + (d.children ? " node--internal" : " node--leaf");
    })
    .classed("enter", true)
    .attr("transform", function(d) {
      return "translate(" + d.y + "," + d.x + ")";
    })
    .attr("id", function(d) {
      let str = d.data.name;
      str = str.replace(/\s/g, '');
      return str;
    });

  nodeEnter.append("circle")
    .attr("r", function(d, i) {
      return 2.5
    });

  var addLeftChild = nodeEnter.append("g")
    .attr("class", "addHandler")
    .attr("id", d => {
      let str = d.data.name;
      str = "addHandler-" + str.replace(/\s/g, '');
      return str;
    })
    .style("opacity", "1")
    .on("click", (d, i, nodes) => addNewLeftChild(d, i, nodes));

  addLeftChild.append("line")
    .attr("x1", -74)
    .attr("y1", 1)
    .attr("x2", -50)
    .attr("y2", 1)
    .attr("stroke", "#85e0e0")
    .style("stroke-width", "2");

  addLeftChild.append("rect")
    .attr("x", "-77")
    .attr("y", "-7")
    .attr("height", 15)
    .attr("width", 15)
    .attr("rx", 5)
    .attr("ry", 5)
    .style("stroke", "#444")
    .style("stroke-width", "1")
    .style("fill", "#ccc");

  addLeftChild.append("line")
    .attr("x1", -74)
    .attr("y1", 1)
    .attr("x2", -65)
    .attr("y2", 1)
    .attr("stroke", "#444")
    .style("stroke-width", "1.5");

  addLeftChild.append("line")
    .attr("x1", -69.5)
    .attr("y1", -3)
    .attr("x2", -69.5)
    .attr("y2", 5)
    .attr("stroke", "#444")
    .style("stroke-width", "1.5");

  // .call(d3.drag().on("drag", dragged));;

  nodeEnter.append("foreignObject")
    .style("fill", "blue")
    .attr("x", -50)
    .attr("y", -7)
    .attr("height", "20px")
    .attr("width", "100px")
    .append('xhtml:div')
    .append('div')
    .attr("class", 'clickable-node')
    .attr("id", function(d) {
      let str = d.data.name;
      str = "div-" + str.replace(/\s/g, '');
      return str;
    })
    .attr("ondblclick", "this.contentEditable=true")
    .attr("onblur", "this.contentEditable=false")
    .attr("contentEditable", "false")
    .style("text-align", "center")
    .text(d => d.data.name);

  //TODO: make it dynamic
  nodeEnter.insert("rect", "foreignObject")
    .attr("ry", 6)
    .attr("rx", 6)
    .attr("y", -10)
    .attr("height", 20)
    .attr("width", 100)
    // .filter(function(d) { return d.flipped; })
    .attr("x", -50)
    .classed("selected", false)
    .attr("id", function(d) {
      let str = d.data.name;
      str = "rect-" + str.replace(/\s/g, '');
      return str;
    });

  var nodeUpdate = nodeEnter.merge(node);
  // Transition to the proper position for the node
  nodeUpdate.transition()
    .duration(750)
    .attr("transform", function(d) {
      return "translate(" + d.y + "," + d.x + ")";
    });

  // Remove any exiting nodes
  var nodeExit = node.exit()
    .transition()
    .duration(750)
    .attr("transform", function(d) {
      return "translate(" + source.y + "," + source.x + ")";
    })
    .remove();

  // On exit reduce the node circles size to 0
  nodeExit.select('circle').attr('r', 0);
  // node = nodeEnter.merge(node)
}

function addNewLeftChild(d, i, nodes) {
  console.log("make new child");
  event.stopPropagation();
  var newNodeObj = {
    // name: new Date().getTime(),
    name: "New Child",
    nodeId: ++currNodeId,
    children: []
  };
  
  console.log("this is ", parsedData)
  //Creates new Node
  var newNode = d3.hierarchy(newNodeObj);
  newNode.depth = d.depth + 1;
  newNode.height = d.height - 1;
  newNode.parent = d;
  newNode.id = Date.now();

  console.log(newNode);
  console.log(d)

  if (d.data.children.length == 0) {
    console.log("i have no children")
    d.children = []
  }
  d.children.push(newNode)
  d.data.children.push(newNode.data)

  console.log(d)
  let foo = d3.hierarchy(parsedData, d => d.children) 
  drawLeft(foo, "left");
}


loadMindMap(parsedList);

.linkMindMap {
    fill: none;
    stroke: #555;
    stroke-opacity: 0.4;
}    
rect {
    fill: white;
    stroke: #3182bd;
    stroke-width: 1.5px;  
 }

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/4.13.0/d3.min.js"></script>
  <div id="div-mindMap">