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<!-- adapted from https://bl.ocks.org/mbostock/4699541 -->
<svg viewBox="0 0 960 600">
<rect width="100%" height="100%" class="background"></rect>
<g></g>
</svg>
<div>click on a state</div>
<script src="https://d3js.org/d3.v5.min.js"></script>
<script src="https://unpkg.com/[email protected]/dist/topojson-client.min.js"></script>
body {
margin: 0;
padding: 0;
font-family: sans-serif;
text-align: center;
font-size: 0.9em;
overflow: hidden;
}
svg {
max-width: 960px;
max-height: 90vh;
stroke-linejoin: round;
stroke-linecap: round;
}
rect.background {
fill: none;
pointer-events: all;
}
path.feature {
stroke-width: 0.75px;
stroke: #fff;
fill: #a6bddb;
cursor: pointer;
}
// adapted from https://bl.ocks.org/mbostock/4699541
var svg = d3.select("svg");
// lookup svg width and height from DOM instead of hard-coding values
var svgWidth = +svg.attr("viewBox").split(" ")[2],
svgHeight = +svg.attr("viewBox").split(" ")[3];
// get reference to the <rect> node, which is invisible and in the background
// wire up a click listener so that the brought up feature can be "reset" later
var rect = svg.select("rect.background").on("click", reset);
// get reference to the <g> node
// geojson features will be drawn here
var g = svg.select("g");
// the D3 geographic path generator is used for drawing the svg paths of geojson
// and during bounding box calculations
var geoPathGenerator = d3.geoPath();
// transition-related vars
var activeFeature = d3.select(null),
transitionDuration = 1250,
featureStrokeWidth = 0.75,
featureStroke = "#fff",
featureFill = "#a6bddb",
// during transition:
// - swap stroke and fill colors
// - change stroke width
broughtUpFeatureStrokeWidth = 3,
broughtUpFeatureStroke = "#a6bddb",
broughtUpFeatureFill = "#fff";
// load and draw US states topojson
d3
.json("https://unpkg.com/[email protected]/us/10m.json")
.then(function(loadedTopoJson) {
var allStatesGeoJsonData = topojson.feature(
loadedTopoJson,
loadedTopoJson.objects.states
);
g
.selectAll("path")
.data(allStatesGeoJsonData.features)
.enter()
.append("path")
.attr("d", geoPathGenerator)
.attr("class", "feature")
.on("click", bringUpFeature);
});
function bringUpFeature(geoJsonDatum) {
if (activeFeature.node() === this) {
return reset();
}
activeFeature.classed("active-feature", false);
activeFeature = d3
.select(this)
.classed("active-feature", true)
.raise();
var t = getGeoBoundsTransform(
geoJsonDatum,
geoPathGenerator,
svgWidth,
svgHeight
);
console.log(t);
activeFeature
.transition()
.duration(transitionDuration)
.style("stroke-width", broughtUpFeatureStrokeWidth / t.scale + "px")
.style("stroke", broughtUpFeatureStroke)
.style("fill", broughtUpFeatureFill)
.attr("transform", "translate(" + t.translate + ") scale(" + t.scale + ")");
var otherFeatures = g.selectAll("path.feature:not(.active-feature)");
// remove the original click listener before transitioning the other features out of view
otherFeatures.on("click", null);
otherFeatures
.transition()
.duration(transitionDuration)
.style("opacity", "0")
.on("end", function(d, idx, nodeList) {
// completely remove the display of the other features after transition is over
if (idx === nodeList.length - 1) {
otherFeatures.style("display", "none");
}
});
}
function reset() {
activeFeature
.transition()
.duration(transitionDuration)
.style("stroke-width", featureStrokeWidth)
.style("stroke", featureStroke)
.style("fill", featureFill)
.attr("transform", "");
var otherFeatures = g.selectAll("path.feature:not(.active-feature)");
// reset display of other features before transitioning back into view
otherFeatures.style("display", "");
otherFeatures
.transition()
.duration(transitionDuration)
.style("opacity", "1")
.on("end", function(d, idx, nodeList) {
// reestablish the original click listener after transition is over
if (idx === nodeList.length - 1) {
otherFeatures.on("click", bringUpFeature);
}
});
activeFeature.classed("active-feature", false);
activeFeature = d3.select(null);
}
function getGeoBoundsTransform(geoJsonDatum, geoPathGenerator, width, height) {
var bounds = geoPathGenerator.bounds(geoJsonDatum),
dx = bounds[1][0] - bounds[0][0],
dy = bounds[1][1] - bounds[0][1],
x = (bounds[0][0] + bounds[1][0]) / 2,
y = (bounds[0][1] + bounds[1][1]) / 2,
scale = 0.9 / Math.max(dx / width, dy / height),
translate = [width / 2 - scale * x, height / 2 - scale * y];
return {
translate: translate,
scale: scale
};
}
Also see: Tab Triggers