如何在 D3 树节点中添加自定义条件颜色？
How to add custom conditional colors in D3 tree nodes?
我正在学习 D3js，我想使用条件为树形图的节点分配颜色。比如数据的类型是“str”，如果是“elem”节点颜色就会变成“read”或者“green”。
我参考了 并添加了条件，但结果所有节点都变成了黑色，而不是“红色”或“绿色”。
有人知道这种行为的原因吗？
这是 D3 代码：
// Set the dimensions and margins of the diagram
//var treeData = data
var treeData = data;
var margin = {top: 20, right: 90, bottom: 30, left: 90},
width = width - margin.left - margin.right,
height = height - margin.top - margin.bottom;
// append the svg object to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
var svg = svg.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 i = 0,
duration = 750,
root;
// declares a tree layout and assigns the size
var treemap = d3.tree().size([height, width]);
// Assigns parent, children, height, depth
root = d3.hierarchy(treeData, function(d) { return d.children; });
root.x0 = height / 2;
root.y0 = 0;
// Collapse after the second level
root.children.forEach(collapse);
update(root);
// Collapse the node and all it's children
function collapse(d) {
if(d.children) {
d._children = d.children
d._children.forEach(collapse)
d.children = null
}
}
function update(source) {
// Assigns the x and y position for the nodes
var treeData = treemap(root);
// Compute the new tree layout.
var nodes = treeData.descendants(),
links = treeData.descendants().slice(1);
// Normalize for fixed-depth.
nodes.forEach(function(d){ d.y = d.depth * 180});
// ****************** Nodes section ***************************
// Update the nodes...
var node = svg.selectAll('g.node')
.data(nodes, function(d) {return d.id || (d.id = ++i); });
// Enter any new modes 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);
// Add Circle for the nodes
nodeEnter.append('circle')
.attr('class', 'node')
.attr('r', 1e-6)
.style("fill", function(d) {
if(d.type == "str") return "red";
if(d.type == "elem") return "green";
});
// Add labels for the nodes
nodeEnter.append('text')
.attr("dy", ".35em")
.attr("x", function(d) {
return d.children || d._children ? -13 : 13;
})
.attr("text-anchor", function(d) {
return d.children || d._children ? "end" : "start";
})
.text(function(d) { return d.data.name; });
// UPDATE
var nodeUpdate = nodeEnter.merge(node);
// Transition to the proper position for the node
nodeUpdate.transition()
.duration(duration)
.attr("transform", function(d) {
return "translate(" + d.y + "," + d.x + ")";
});
// Update the node attributes and style
nodeUpdate.select('circle.node')
.attr('r', 10)
.style("fill", function(d) {
if(d.type == "str") return "red";
if(d.type == "elem") return "green";
})
.attr('cursor', 'pointer');
// Remove any exiting nodes
var nodeExit = node.exit().transition()
.duration(duration)
.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', 1e-6);
// On exit reduce the opacity of text labels
nodeExit.select('text')
.style('fill-opacity', 1e-6);
// ****************** links section ***************************
// Update the links...
var link = svg.selectAll('path.link')
.data(links, function(d) { return d.id; });
// Enter any new links at the parent's previous position.
var linkEnter = link.enter().insert('path', "g")
.attr("class", "link")
.attr('d', function(d){
var o = {x: source.x0, y: source.y0}
return diagonal(o, o)
});
// UPDATE
var linkUpdate = linkEnter.merge(link);
// Transition back to the parent element position
linkUpdate.transition()
.duration(duration)
.attr('d', function(d){ return diagonal(d, d.parent) });
// Remove any exiting links
var linkExit = link.exit().transition()
.duration(duration)
.attr('d', function(d) {
var o = {x: source.x, y: source.y}
return diagonal(o, o)
})
.remove();
// Store the old positions for transition.
nodes.forEach(function(d){
d.x0 = d.x;
d.y0 = d.y;
});
// Creates a curved (diagonal) path from parent to the child nodes
function diagonal(s, d) {
path = `M ${s.y} ${s.x}
C ${(s.y + d.y) / 2} ${s.x},
${(s.y + d.y) / 2} ${d.x},
${d.y} ${d.x}`
return path
}
// 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);
}
}
数据：
{
"type": "str",
"name": "Canada",
"children": [
{
"type": "elem",
"name": "Newfoundland",
"children": [
{
"type": "str",
"name": "St. John's"
}
]
},
{
"type": "elem",
"name": "PEI",
"children": [
{
"type": "str",
"name": "Charlottetown"
}
]
},
{
"type": "elem",
"name": "Nova Scotia",
"children": [
{
"type": "str",
"name": "Halifax"
}
]
}
]
}
D3-hiearchy 产生一个新的数据数组，为了避免层次结构的属性和数据的属性之间的冲突，它将与给定节点关联的数据放入data 属性。
D3-hierarchy 这样做是为了保留原始数据，例如，您的数据有一个 children 属性，d3-hierarchy 生成的一组节点也有一个 children 属性，所以为了保留两者并避免冲突，将原始数据移动到data 属性。
所以您需要使用 d.data.type.
而不是 d.type
作为参考，d3-hierarchy 返回的每个节点只有以下属性：
node.data - the associated data, as specified to the constructor.
node.depth - zero for the root node, and increasing by one for each descendant generation.
node.height - zero for leaf nodes, and the greatest distance from any descendant leaf for internal nodes.
node.parent - the parent node, or null for the root node.
node.children - an array of child nodes, if any; undefined for leaf nodes.
node.value - the summed value of the node and its descendants; optional, see node.sum and node.count.
（来自 docs）
我正在学习 D3js，我想使用条件为树形图的节点分配颜色。比如数据的类型是“str”，如果是“elem”节点颜色就会变成“read”或者“green”。
我参考了
有人知道这种行为的原因吗？
这是 D3 代码：
// Set the dimensions and margins of the diagram
//var treeData = data
var treeData = data;
var margin = {top: 20, right: 90, bottom: 30, left: 90},
width = width - margin.left - margin.right,
height = height - margin.top - margin.bottom;
// append the svg object to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
var svg = svg.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 i = 0,
duration = 750,
root;
// declares a tree layout and assigns the size
var treemap = d3.tree().size([height, width]);
// Assigns parent, children, height, depth
root = d3.hierarchy(treeData, function(d) { return d.children; });
root.x0 = height / 2;
root.y0 = 0;
// Collapse after the second level
root.children.forEach(collapse);
update(root);
// Collapse the node and all it's children
function collapse(d) {
if(d.children) {
d._children = d.children
d._children.forEach(collapse)
d.children = null
}
}
function update(source) {
// Assigns the x and y position for the nodes
var treeData = treemap(root);
// Compute the new tree layout.
var nodes = treeData.descendants(),
links = treeData.descendants().slice(1);
// Normalize for fixed-depth.
nodes.forEach(function(d){ d.y = d.depth * 180});
// ****************** Nodes section ***************************
// Update the nodes...
var node = svg.selectAll('g.node')
.data(nodes, function(d) {return d.id || (d.id = ++i); });
// Enter any new modes 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);
// Add Circle for the nodes
nodeEnter.append('circle')
.attr('class', 'node')
.attr('r', 1e-6)
.style("fill", function(d) {
if(d.type == "str") return "red";
if(d.type == "elem") return "green";
});
// Add labels for the nodes
nodeEnter.append('text')
.attr("dy", ".35em")
.attr("x", function(d) {
return d.children || d._children ? -13 : 13;
})
.attr("text-anchor", function(d) {
return d.children || d._children ? "end" : "start";
})
.text(function(d) { return d.data.name; });
// UPDATE
var nodeUpdate = nodeEnter.merge(node);
// Transition to the proper position for the node
nodeUpdate.transition()
.duration(duration)
.attr("transform", function(d) {
return "translate(" + d.y + "," + d.x + ")";
});
// Update the node attributes and style
nodeUpdate.select('circle.node')
.attr('r', 10)
.style("fill", function(d) {
if(d.type == "str") return "red";
if(d.type == "elem") return "green";
})
.attr('cursor', 'pointer');
// Remove any exiting nodes
var nodeExit = node.exit().transition()
.duration(duration)
.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', 1e-6);
// On exit reduce the opacity of text labels
nodeExit.select('text')
.style('fill-opacity', 1e-6);
// ****************** links section ***************************
// Update the links...
var link = svg.selectAll('path.link')
.data(links, function(d) { return d.id; });
// Enter any new links at the parent's previous position.
var linkEnter = link.enter().insert('path', "g")
.attr("class", "link")
.attr('d', function(d){
var o = {x: source.x0, y: source.y0}
return diagonal(o, o)
});
// UPDATE
var linkUpdate = linkEnter.merge(link);
// Transition back to the parent element position
linkUpdate.transition()
.duration(duration)
.attr('d', function(d){ return diagonal(d, d.parent) });
// Remove any exiting links
var linkExit = link.exit().transition()
.duration(duration)
.attr('d', function(d) {
var o = {x: source.x, y: source.y}
return diagonal(o, o)
})
.remove();
// Store the old positions for transition.
nodes.forEach(function(d){
d.x0 = d.x;
d.y0 = d.y;
});
// Creates a curved (diagonal) path from parent to the child nodes
function diagonal(s, d) {
path = `M ${s.y} ${s.x}
C ${(s.y + d.y) / 2} ${s.x},
${(s.y + d.y) / 2} ${d.x},
${d.y} ${d.x}`
return path
}
// 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);
}
}
数据：
{
"type": "str",
"name": "Canada",
"children": [
{
"type": "elem",
"name": "Newfoundland",
"children": [
{
"type": "str",
"name": "St. John's"
}
]
},
{
"type": "elem",
"name": "PEI",
"children": [
{
"type": "str",
"name": "Charlottetown"
}
]
},
{
"type": "elem",
"name": "Nova Scotia",
"children": [
{
"type": "str",
"name": "Halifax"
}
]
}
]
}
D3-hiearchy 产生一个新的数据数组，为了避免层次结构的属性和数据的属性之间的冲突，它将与给定节点关联的数据放入data 属性。
D3-hierarchy 这样做是为了保留原始数据，例如，您的数据有一个 children 属性，d3-hierarchy 生成的一组节点也有一个 children 属性，所以为了保留两者并避免冲突，将原始数据移动到data 属性。
所以您需要使用 d.data.type.
d.type
作为参考，d3-hierarchy 返回的每个节点只有以下属性：
node.data - the associated data, as specified to the constructor.
node.depth - zero for the root node, and increasing by one for each descendant generation.
node.height - zero for leaf nodes, and the greatest distance from any descendant leaf for internal nodes.
node.parent - the parent node, or null for the root node.
node.children - an array of child nodes, if any; undefined for leaf nodes.
node.value - the summed value of the node and its descendants; optional, see node.sum and node.count.
（来自 docs）