我知道这个问题已经问过很多次了,但是我无法解决更新饼图的问题。我完全迷路了。您能告诉我这里的问题是什么吗?
我尝试了以下方法,但是图表似乎没有更新。我添加了应该更新图表的功能更改。我正在更新数据,重画弧线并更改标签,但是它不起作用。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- Load D3 -->
<script src="https://d3js.org/d3.v5.min.js"></script>
<title>Document</title>
</head>
<body>
<div id="pie"></div>
<script>
var dataChart = { a: 9, b: 20, c: 30, d: 8, e: 12 };
var dataChart2 = { f: 9, g: 20, h: 30, i: 8 };
console.log(dataChart);
var width = 300,
height = 300,
// Think back to 5th grade. Radius is 1/2 of the diameter. What is the limiting factor on the diameter? Width or height, whichever is smaller
radius = Math.min(width, height) / 2;
var color = d3.scaleOrdinal()
.range(["#2C93E8", "#838690", "#F56C4E"]);
var pie = d3.pie()
.value(function (d) { return d.value; });
data = pie(d3.entries(dataChart));
var arc = d3.arc()
.outerRadius(radius - 10)
.innerRadius(0);
var labelArc = d3.arc()
.outerRadius(radius - 40)
.innerRadius(radius - 40);
var svg = d3.select("#pie")
.append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")"); // Moving the center point. 1/2 the width and 1/2 the height
var g = svg.selectAll("arc")
.data(data)
.enter().append("g")
.attr("class", "arc");
g.append("path")
.attr("d", arc)
.style("fill", function (d) { return color(d.data.key); });
g.append("text")
.attr("transform", function (d) { return "translate(" + labelArc.centroid(d) + ")"; })
.text(function (d) { return d.data.key; })
.style("fill", "#fff");
function change(dataChart) {
var pie = d3.pie()
.value(function (d) { return d.value; });
data = pie(d3.entries(dataChart));
path = d3.select("#pie").selectAll("path").data(data); // Compute the new angles
path.attr("d", arc); // redrawing the path
d3.selectAll("text").data(data).attr("transform", function (d) { return "translate(" + labelArc.centroid(d) + ")"; }); // recomputing the centroid and translating the text accordingly.
}
// calling the update functions
change(dataChart);
change (dataChart2);
</script>
</body>
</html>