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@lazingor
Last active May 14, 2019 21:52
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Update child data when parent data is updated?
license: mit
<!DOCTYPE html>
<head>
<meta charset="utf-8">
<script src="https://d3js.org/d3.v4.min.js"></script>
<style>
body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
</style>
</head>
<body>
<script>
var sampleData = [ [50,50], [100,100] ];
var svg = d3.select("body")
.append("svg")
.attr("width", "500px")
.attr("height", "400px")
.attr("style", "background: #eee");
function update(dataArr) {
var groups = svg.selectAll(".group").data(dataArr);
var gsEnter = groups.enter().append("g").attr("class", "group");
gsEnter.append("rect")
.attr("class", "myrect")
.attr("width", "50px")
.attr("height", "50px")
.attr("fill", "black");
gsEnter.append("circle")
.attr("class", "mycirc")
.attr("r", "25px")
.attr("fill", "blue");
groups = groups.merge(gsEnter);
groups.select(".myrect")
.transition()
.attr("x", function(d) { return d[0]; })
.attr("y", function(d) { return d[1]; });
groups.select(".mycirc")
.transition()
.attr("cx", function(d) { return d[0]+50; })
.attr("cy", function(d) { return d[1]; });
}
update(sampleData);
d3.select("body").append("button").text("Update").on("click", newData);
function newData() {
sampleData = [ [100,200], [150,300], [200,350] ];
update(sampleData);
// What happens: the two already created rect+circle pairs stay where they are, and a new one is placed at [200,350]
// What I want: the two already created rect+circle pairs to map to the new coordinates, and the new one to be created
}
</script>
</body>
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