In my angularjs project I'm using d3js to build a 'collapsible tree' and I used the code from this example
Now I want to make each link have different color based on certain data.
What I tried first is to change the stroke of the gLink
from
const gLink = svg.append("g")
.attr("fill", "none")
.attr("stroke", "#555")
.attr("stroke-opacity", 0.4)
.attr("stroke-width", 1.5);
to
const gLink = svg.append("g")
.attr("fill", "none")
.attr("stroke", getLinkColor())
.attr("stroke-opacity", 0.4)
.attr("stroke-width", 1.5);
var getLinkColor = function () {
var num = Math.floor(Math.random() * 2);
return num ? "#555" : "red";
};
However this will make all the link colours either red or #555 when the page loads.
So what I tried next is to change the links stroke inside the update function:
function update(event, source) {
gLink = gLink.attr("stroke", getLinkColor());
const duration = event?.altKey ? 2500 : 250;
etc...
}
However this also produces the same result as in the first case and I've been unable since to figure out the solution.
You need to set the color on the link's path element. Here I've made it conditional on the depth of the link:
// Enter any new links at the parent's previous position.
const linkEnter = link
.enter()
.append('path')
.attr('stroke', (d) => d.source.depth % 2 == 0 ? 'steelblue' : 'orange')
.attr('d', (d) => {
const o = { x: source.x0, y: source.y0 };
return diagonal({ source: o, target: o });
});
Essentially create an array of all the node names with children. Use this array as the domain for a color scale and then assign the link color based on that.
<!DOCTYPE html>
<html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/7.9.0/d3.js"></script>
</head>
<body>
<svg></svg>
<script>
const data = {
name: 'flare',
children: [
{
name: 'analytics',
children: [
{
name: 'cluster',
children: [
{ name: 'AgglomerativeCluster', value: 3938 },
{ name: 'CommunityStructure', value: 3812 },
{ name: 'HierarchicalCluster', value: 6714 },
{ name: 'MergeEdge', value: 743 },
],
},
{
name: 'graph',
children: [
{ name: 'BetweennessCentrality', value: 3534 },
{ name: 'LinkDistance', value: 5731 },
{ name: 'MaxFlowMinCut', value: 7840 },
{ name: 'ShortestPaths', value: 5914 },
{ name: 'SpanningTree', value: 3416 },
],
},
{
name: 'optimization',
children: [{ name: 'AspectRatioBanker', value: 7074 }],
},
],
},
{
name: 'animate',
children: [
{ name: 'Easing', value: 17010 },
{ name: 'FunctionSequence', value: 5842 },
{
name: 'interpolate',
children: [
{ name: 'ArrayInterpolator', value: 1983 },
{ name: 'ColorInterpolator', value: 2047 },
{ name: 'DateInterpolator', value: 1375 },
{ name: 'Interpolator', value: 8746 },
{ name: 'MatrixInterpolator', value: 2202 },
{ name: 'NumberInterpolator', value: 1382 },
{ name: 'ObjectInterpolator', value: 1629 },
{ name: 'PointInterpolator', value: 1675 },
{ name: 'RectangleInterpolator', value: 2042 },
],
},
{ name: 'ISchedulable', value: 1041 },
{ name: 'Parallel', value: 5176 },
{ name: 'Pause', value: 449 },
{ name: 'Scheduler', value: 5593 },
{ name: 'Sequence', value: 5534 },
{ name: 'Transition', value: 9201 },
{ name: 'Transitioner', value: 19975 },
{ name: 'TransitionEvent', value: 1116 },
{ name: 'Tween', value: 6006 },
],
},
{
name: 'data',
children: [
{
name: 'converters',
children: [
{ name: 'Converters', value: 721 },
{ name: 'DelimitedTextConverter', value: 4294 },
{ name: 'GraphMLConverter', value: 9800 },
{ name: 'IDataConverter', value: 1314 },
{ name: 'JSONConverter', value: 2220 },
],
},
{ name: 'DataField', value: 1759 },
{ name: 'DataSchema', value: 2165 },
{ name: 'DataSet', value: 586 },
{ name: 'DataSource', value: 3331 },
{ name: 'DataTable', value: 772 },
{ name: 'DataUtil', value: 3322 },
],
},
{
name: 'display',
children: [
{ name: 'DirtySprite', value: 8833 },
{ name: 'LineSprite', value: 1732 },
{ name: 'RectSprite', value: 3623 },
{ name: 'TextSprite', value: 10066 },
],
},
{ name: 'flex', children: [{ name: 'FlareVis', value: 4116 }] },
{
name: 'physics',
children: [
{ name: 'DragForce', value: 1082 },
{ name: 'GravityForce', value: 1336 },
{ name: 'IForce', value: 319 },
{ name: 'NBodyForce', value: 10498 },
{ name: 'Particle', value: 2822 },
{ name: 'Simulation', value: 9983 },
{ name: 'Spring', value: 2213 },
{ name: 'SpringForce', value: 1681 },
],
},
{
name: 'query',
children: [
{ name: 'AggregateExpression', value: 1616 },
{ name: 'And', value: 1027 },
{ name: 'Arithmetic', value: 3891 },
{ name: 'Average', value: 891 },
{ name: 'BinaryExpression', value: 2893 },
{ name: 'Comparison', value: 5103 },
{ name: 'CompositeExpression', value: 3677 },
{ name: 'Count', value: 781 },
{ name: 'DateUtil', value: 4141 },
{ name: 'Distinct', value: 933 },
{ name: 'Expression', value: 5130 },
{ name: 'ExpressionIterator', value: 3617 },
{ name: 'Fn', value: 3240 },
{ name: 'If', value: 2732 },
{ name: 'IsA', value: 2039 },
{ name: 'Literal', value: 1214 },
{ name: 'Match', value: 3748 },
{ name: 'Maximum', value: 843 },
{
name: 'methods',
children: [
{ name: 'add', value: 593 },
{ name: 'and', value: 330 },
{ name: 'average', value: 287 },
{ name: 'count', value: 277 },
{ name: 'distinct', value: 292 },
{ name: 'div', value: 595 },
{ name: 'eq', value: 594 },
{ name: 'fn', value: 460 },
{ name: 'gt', value: 603 },
{ name: 'gte', value: 625 },
{ name: 'iff', value: 748 },
{ name: 'isa', value: 461 },
{ name: 'lt', value: 597 },
{ name: 'lte', value: 619 },
{ name: 'max', value: 283 },
{ name: 'min', value: 283 },
{ name: 'mod', value: 591 },
{ name: 'mul', value: 603 },
{ name: 'neq', value: 599 },
{ name: 'not', value: 386 },
{ name: 'or', value: 323 },
{ name: 'orderby', value: 307 },
{ name: 'range', value: 772 },
{ name: 'select', value: 296 },
{ name: 'stddev', value: 363 },
{ name: 'sub', value: 600 },
{ name: 'sum', value: 280 },
{ name: 'update', value: 307 },
{ name: 'variance', value: 335 },
{ name: 'where', value: 299 },
{ name: 'xor', value: 354 },
{ name: '_', value: 264 },
],
},
{ name: 'Minimum', value: 843 },
{ name: 'Not', value: 1554 },
{ name: 'Or', value: 970 },
{ name: 'Query', value: 13896 },
{ name: 'Range', value: 1594 },
{ name: 'StringUtil', value: 4130 },
{ name: 'Sum', value: 791 },
{ name: 'Variable', value: 1124 },
{ name: 'Variance', value: 1876 },
{ name: 'Xor', value: 1101 },
],
},
{
name: 'scale',
children: [
{ name: 'IScaleMap', value: 2105 },
{ name: 'LinearScale', value: 1316 },
{ name: 'LogScale', value: 3151 },
{ name: 'OrdinalScale', value: 3770 },
{ name: 'QuantileScale', value: 2435 },
{ name: 'QuantitativeScale', value: 4839 },
{ name: 'RootScale', value: 1756 },
{ name: 'Scale', value: 4268 },
{ name: 'ScaleType', value: 1821 },
{ name: 'TimeScale', value: 5833 },
],
},
{
name: 'util',
children: [
{ name: 'Arrays', value: 8258 },
{ name: 'Colors', value: 10001 },
{ name: 'Dates', value: 8217 },
{ name: 'Displays', value: 12555 },
{ name: 'Filter', value: 2324 },
{ name: 'Geometry', value: 10993 },
{
name: 'heap',
children: [
{ name: 'FibonacciHeap', value: 9354 },
{ name: 'HeapNode', value: 1233 },
],
},
{ name: 'IEvaluable', value: 335 },
{ name: 'IPredicate', value: 383 },
{ name: 'IValueProxy', value: 874 },
{
name: 'math',
children: [
{ name: 'DenseMatrix', value: 3165 },
{ name: 'IMatrix', value: 2815 },
{ name: 'SparseMatrix', value: 3366 },
],
},
{ name: 'Maths', value: 17705 },
{ name: 'Orientation', value: 1486 },
{
name: 'palette',
children: [
{ name: 'ColorPalette', value: 6367 },
{ name: 'Palette', value: 1229 },
{ name: 'ShapePalette', value: 2059 },
{ name: 'SizePalette', value: 2291 },
],
},
{ name: 'Property', value: 5559 },
{ name: 'Shapes', value: 19118 },
{ name: 'Sort', value: 6887 },
{ name: 'Stats', value: 6557 },
{ name: 'Strings', value: 22026 },
],
},
{
name: 'vis',
children: [
{
name: 'axis',
children: [
{ name: 'Axes', value: 1302 },
{ name: 'Axis', value: 24593 },
{ name: 'AxisGridLine', value: 652 },
{ name: 'AxisLabel', value: 636 },
{ name: 'CartesianAxes', value: 6703 },
],
},
{
name: 'controls',
children: [
{ name: 'AnchorControl', value: 2138 },
{ name: 'ClickControl', value: 3824 },
{ name: 'Control', value: 1353 },
{ name: 'ControlList', value: 4665 },
{ name: 'DragControl', value: 2649 },
{ name: 'ExpandControl', value: 2832 },
{ name: 'HoverControl', value: 4896 },
{ name: 'IControl', value: 763 },
{ name: 'PanZoomControl', value: 5222 },
{ name: 'SelectionControl', value: 7862 },
{ name: 'TooltipControl', value: 8435 },
],
},
{
name: 'data',
children: [
{ name: 'Data', value: 20544 },
{ name: 'DataList', value: 19788 },
{ name: 'DataSprite', value: 10349 },
{ name: 'EdgeSprite', value: 3301 },
{ name: 'NodeSprite', value: 19382 },
{
name: 'render',
children: [
{ name: 'ArrowType', value: 698 },
{ name: 'EdgeRenderer', value: 5569 },
{ name: 'IRenderer', value: 353 },
{ name: 'ShapeRenderer', value: 2247 },
],
},
{ name: 'ScaleBinding', value: 11275 },
{ name: 'Tree', value: 7147 },
{ name: 'TreeBuilder', value: 9930 },
],
},
{
name: 'events',
children: [
{ name: 'DataEvent', value: 2313 },
{ name: 'SelectionEvent', value: 1880 },
{ name: 'TooltipEvent', value: 1701 },
{ name: 'VisualizationEvent', value: 1117 },
],
},
{
name: 'legend',
children: [
{ name: 'Legend', value: 20859 },
{ name: 'LegendItem', value: 4614 },
{ name: 'LegendRange', value: 10530 },
],
},
{
name: 'operator',
children: [
{
name: 'distortion',
children: [
{ name: 'BifocalDistortion', value: 4461 },
{ name: 'Distortion', value: 6314 },
{ name: 'FisheyeDistortion', value: 3444 },
],
},
{
name: 'encoder',
children: [
{ name: 'ColorEncoder', value: 3179 },
{ name: 'Encoder', value: 4060 },
{ name: 'PropertyEncoder', value: 4138 },
{ name: 'ShapeEncoder', value: 1690 },
{ name: 'SizeEncoder', value: 1830 },
],
},
{
name: 'filter',
children: [
{ name: 'FisheyeTreeFilter', value: 5219 },
{ name: 'GraphDistanceFilter', value: 3165 },
{ name: 'VisibilityFilter', value: 3509 },
],
},
{ name: 'IOperator', value: 1286 },
{
name: 'label',
children: [
{ name: 'Labeler', value: 9956 },
{ name: 'RadialLabeler', value: 3899 },
{ name: 'StackedAreaLabeler', value: 3202 },
],
},
{
name: 'layout',
children: [
{ name: 'AxisLayout', value: 6725 },
{ name: 'BundledEdgeRouter', value: 3727 },
{ name: 'CircleLayout', value: 9317 },
{ name: 'CirclePackingLayout', value: 12003 },
{ name: 'DendrogramLayout', value: 4853 },
{ name: 'ForceDirectedLayout', value: 8411 },
{ name: 'IcicleTreeLayout', value: 4864 },
{ name: 'IndentedTreeLayout', value: 3174 },
{ name: 'Layout', value: 7881 },
{ name: 'NodeLinkTreeLayout', value: 12870 },
{ name: 'PieLayout', value: 2728 },
{ name: 'RadialTreeLayout', value: 12348 },
{ name: 'RandomLayout', value: 870 },
{ name: 'StackedAreaLayout', value: 9121 },
{ name: 'TreeMapLayout', value: 9191 },
],
},
{ name: 'Operator', value: 2490 },
{ name: 'OperatorList', value: 5248 },
{ name: 'OperatorSequence', value: 4190 },
{ name: 'OperatorSwitch', value: 2581 },
{ name: 'SortOperator', value: 2023 },
],
},
{ name: 'Visualization', value: 16540 },
],
},
],
};
// Specify the charts’ dimensions. The height is variable, depending on the layout.
const width = 928;
const marginTop = 10;
const marginRight = 10;
const marginBottom = 10;
const marginLeft = 40;
// Rows are separated by dx pixels, columns by dy pixels. These names can be counter-intuitive
// (dx is a height, and dy a width). This because the tree must be viewed with the root at the
// “bottom”, in the data domain. The width of a column is based on the tree’s height.
const root = d3.hierarchy(data);
const dx = 10;
const dy = (width - marginRight - marginLeft) / (1 + root.height);
// Define the tree layout and the shape for links.
const tree = d3.tree().nodeSize([dx, dy]);
const diagonal = d3
.linkHorizontal()
.x((d) => d.y)
.y((d) => d.x);
// Create the SVG container, a layer for the links and a layer for the nodes.
const svg = d3
.select('svg')
.attr('width', width)
.attr('height', dx)
.attr('viewBox', [-marginLeft, -marginTop, width, dx])
.attr(
'style',
'max-width: 100%; height: auto; font: 10px sans-serif; user-select: none;'
);
const gLink = svg
.append('g')
.attr('fill', 'none')
.attr('stroke', '#555')
.attr('stroke-opacity', 0.4)
.attr('stroke-width', 1.5);
const gNode = svg
.append('g')
.attr('cursor', 'pointer')
.attr('pointer-events', 'all');
function update(event, source) {
const duration = event?.altKey ? 2500 : 250; // hold the alt key to slow down the transition
const nodes = root.descendants().reverse();
const links = root.links();
// Compute the new tree layout.
tree(root);
let left = root;
let right = root;
root.eachBefore((node) => {
if (node.x < left.x) left = node;
if (node.x > right.x) right = node;
});
const height = right.x - left.x + marginTop + marginBottom;
const transition = svg
.transition()
.duration(duration)
.attr('height', height)
.attr('viewBox', [-marginLeft, left.x - marginTop, width, height])
.tween(
'resize',
window.ResizeObserver ? null : () => () => svg.dispatch('toggle')
);
// Update the nodes…
const node = gNode.selectAll('g').data(nodes, (d) => d.id);
// Enter any new nodes at the parent's previous position.
const nodeEnter = node
.enter()
.append('g')
.attr('transform', (d) => `translate(${source.y0},${source.x0})`)
.attr('fill-opacity', 0)
.attr('stroke-opacity', 0)
.on('click', (event, d) => {
d.children = d.children ? null : d._children;
update(event, d);
});
nodeEnter
.append('circle')
.attr('r', 2.5)
.attr('fill', (d) => (d._children ? '#555' : '#999'))
.attr('stroke-width', 10);
nodeEnter
.append('text')
.attr('dy', '0.31em')
.attr('x', (d) => (d._children ? -6 : 6))
.attr('text-anchor', (d) => (d._children ? 'end' : 'start'))
.text((d) => d.data.name)
.attr('stroke-linejoin', 'round')
.attr('stroke-width', 3)
.attr('stroke', 'white')
.attr('paint-order', 'stroke');
// Transition nodes to their new position.
const nodeUpdate = node
.merge(nodeEnter)
.transition(transition)
.attr('transform', (d) => `translate(${d.y},${d.x})`)
.attr('fill-opacity', 1)
.attr('stroke-opacity', 1);
// Transition exiting nodes to the parent's new position.
const nodeExit = node
.exit()
.transition(transition)
.remove()
.attr('transform', (d) => `translate(${source.y},${source.x})`)
.attr('fill-opacity', 0)
.attr('stroke-opacity', 0);
// Update the links…
const link = gLink.selectAll('path').data(links, (d) => d.target.id);
const reCurNames = (node) => {
if (!node.children) return;
allNames.push(node.name);
node.children.forEach(child => reCurNames(child));
};
const allNames = [];
reCurNames(data);
const linkColor = d3.scaleOrdinal(d3.schemeCategory10)
.domain(allNames);
const linkEnter = link
.enter()
.append('path')
.attr('stroke', (d) => linkColor(d.source.data.name))
.attr('d', (d) => {
const o = { x: source.x0, y: source.y0 };
return diagonal({ source: o, target: o });
});
// Transition links to their new position.
link.merge(linkEnter).transition(transition).attr('d', diagonal);
// Transition exiting nodes to the parent's new position.
link
.exit()
.transition(transition)
.remove()
.attr('d', (d) => {
const o = { x: source.x, y: source.y };
return diagonal({ source: o, target: o });
});
// Stash the old positions for transition.
root.eachBefore((d) => {
d.x0 = d.x;
d.y0 = d.y;
});
}
// Do the first update to the initial configuration of the tree — where a number of nodes
// are open (arbitrarily selected as the root, plus nodes with 7 letters).
root.x0 = dy / 2;
root.y0 = 0;
root.descendants().forEach((d, i) => {
d.id = i;
d._children = d.children;
if (d.depth && d.data.name.length !== 7) d.children = null;
});
update(null, root);
</script>
</body>
</html>