基于d3.js实现实时刷新的折线图
投稿：daisy
本文用实例演示如何用d3.js实现实时刷新的折线图,非常具有实用价值,需要的朋友可以参考下。
先来看看效果图
下面直接上源代码，html文件
<html>
<head>
<meta charset="utf-8">
<title>实时刷新折线图</title>
<style>
.axis path,
.axis line{
fill: none;
stroke: black;
shape-rendering: crispEdges;
}
.axis text {
font-family: sans-serif;
font-size: 11px;
}
.overlay {
fill: none;
pointer-events: all;
}
.tooltip{
width: 150px;
height: auto;
position: absolute;
font-family: simsun;
font-size: 16px;
line-height: 26px;
text-align: left;
border: 1px solid black;
background-color: white;
border-radius: 5px;
}
.tooltip .title{
border-bottom: 1px solid #000;
text-align: center;
}
.tooltip .desColor{
width: 10px;
height: 10px;
float: left;
margin: 9px 8px 1px 8px;
}
.tooltip .desText{
display: inline;
}
.focusLine {
stroke: black;
stroke-width: 1px;
stroke-dasharray: 5,5;
}
</style>
</head>
<body>
<script src="http://d3js.org/d3.v3.js" charset="utf-8"></script>
<script src="linechart.js" charset="utf-8"></script>
<svg contentScriptType="text/ecmascript" width="2000" xmlns:xlink="http://www.w3.org/1999/xlink" zoomAndPan="magnify" style="background-color:#ffffff;" contentStyleType="text/css" viewBox="0 0 2000.0 2000.0" height="2000" preserveAspectRatio="xMidYMid meet" xmlns="http://www.w3.org/2000/svg" version="1.0">
<defs>
<symbol id="fillgauge1" viewBox="0 0 500.0 300.0" preserveAspectRatio="none meet">
</symbol>
<symbol id="fillgauge2" viewBox="0 0 200.0 200.0" preserveAspectRatio="none meet">
</symbol>
</defs>
<use x="0" y="0" width="500" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#fillgauge1" xlink:type="simple" xlink:actuate="onLoad" symboltype="17" height="300" xlink:show="embed"/>
<use x="20" y="20" width="50" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#fillgauge2" xlink:type="simple" xlink:actuate="onLoad" symboltype="17" height="180" xlink:show="embed"/>
</svg>
<script>
var dataset = [
{
country: "china",
gdp: [[2000,11920],[2001,13170],[2002,14550],
[2003,16500],[2004,19440],[2005,22870],
[2006,27930],[2007,35040],[2008,45470],
[2009,51050],[2010,59490],[2011,73140],
[2012,83860],[2013,103550]]
},
{
country: "usa",
gdp: [[2000,47310],[2001,41590],[2002,39800],
[2003,43020],[2004,46550],[2005,45710],
[2006,43560],[2007,43560],[2008,48490],
[2009,50350],[2010,54950],[2011,59050],
[2012,59370],[2013,48980]]
}
];
var gauge1=loadLineChart("fillgauge1",dataset);
function NewValue(){
if(Math.random() > .5){
return Math.round(Math.random()*100);
} else {
return (Math.random()*100).toFixed(1);
}
}
function refreshLine(gauge1){
//alert("hehe");
// document.getElementById("fillgauge1").innerHTML="";
var updateData =[
{
country: "china",
gdp: [[2000,NewValue()],[2001,NewValue()],[2002,NewValue()],
[2003,NewValue()],[2004,NewValue()],[2005,NewValue()],
[2006,NewValue()],[2007,NewValue()],[2008,NewValue()],
[2009,NewValue()],[2010,NewValue()],[2011,NewValue()],
[2012,NewValue()],[2013,NewValue()]]
},
{
country: "usa",
gdp: [[2000,NewValue()],[2001,NewValue()],[2002,NewValue()],
[2003,NewValue()],[2004,NewValue()],[2005,NewValue()],
[2006,NewValue()],[2007,NewValue()],[2008,NewValue()],
[2009,NewValue()],[2010,NewValue()],[2011,NewValue()],
[2012,NewValue()],[2013,NewValue()]]
}
];
gauge1.update(updateData);
}
self.setInterval("refreshLine(gauge1)",5000);
</script>
</body>
</html>
lineChart.js负责加载和刷新折线图
function loadLineChart(elementId, dataset) {
var svg = d3.select("#" + elementId);
var strs = svg.attr("viewBox").split(" ");
alert(dataset);
var width = strs[2];
var height = strs[3];
//外边框
var padding = {
top : 50,
right : 50,
bottom : 50,
left : 50
};
var names = new Array();
//计算GDP的最大值
var gdpmax = 0;
for (var i = 0; i < dataset.length; i++) {
var currGdp = d3.max(dataset[i].gdp, function (d) {
return d[1];
});
if (currGdp > gdpmax)
gdpmax = currGdp;
}
var gdpnumb = dataset[0].gdp.length;
for (var j = 0; j < gdpnumb; j++) {
names[j] = (dataset[0].gdp[j])[0];
}
alert(names);
var xScale = d3.scale.linear()
.domain([2000, 2013])
.range([0, width - padding.left - padding.right]);
// var xScale = d3.scale.ordinal()
// .domain(names)
// .rangeRoundBands([0, width - padding.left - padding.right]);
var yScale = d3.scale.linear()
.domain([0, gdpmax * 1.1])
.range([height - padding.top - padding.bottom, 0]);
//创建一个直线生成器
var linePath = d3.svg.line()
.x(function (d) {
return xScale(d[0]);
})
.y(function (d) {
return yScale(d[1]);
})
.interpolate("basis");
//定义两个颜色
var colors = [d3.rgb(0, 0, 255), d3.rgb(0, 255, 0)];
//添加路径
svg.selectAll("path") //选择<svg>中所有的<path>
.data(dataset) //绑定数据
.enter() //选择enter部分
.append("path") //添加足够数量的<path>元素
.attr("transform", "translate(" + padding.left + "," + padding.top + ")")
.attr("d", function (d) {
return linePath(d.gdp); //返回直线生成器得到的路径
})
.attr("fill", "none")
.attr("stroke-width", 3)
.attr("stroke", function (d, i) {
return colors[i];
});
//添加垂直于x轴的对齐线
var vLine = svg.append("line")
.attr("class", "focusLine")
.style("display", "none");
//添加一个提示框
var tooltip = d3.select("body")
.append("div")
.attr("class", "tooltip")
.style("opacity", 0.0);
var title = tooltip.append("div")
.attr("class", "title");
var des = tooltip.selectAll(".des")
.data(dataset)
.enter()
.append("div");
var desColor = des.append("div")
.attr("class", "desColor");
var desText = des.append("div")
.attr("class", "desText");
//添加一个透明的监视鼠标事件用的矩形
svg.append("rect")
.attr("class", "overlay")
.attr("x", padding.left)
.attr("y", padding.top)
.attr("width", width - padding.left - padding.right)
.attr("height", height - padding.top - padding.bottom)
.on("mouseover", function () {
tooltip.style("left", (d3.event.pageX) + "px")
.style("top", (d3.event.pageY + 20) + "px")
.style("opacity", 1.0);
vLine.style("display", null);
})
.on("mouseout", function () {
tooltip.style("opacity", 0.0);
vLine.style("display", "none");
})
.on("mousemove", mousemove);
function mousemove() {
/* 当鼠标在透明矩形内滑动时调用 */
//折线的源数组
var data = dataset[0].gdp;
//获取鼠标相对于透明矩形左上角的坐标，左上角坐标为(0,0)
var mouseX = d3.mouse(this)[0] - padding.left;
var mouseY = d3.mouse(this)[1] - padding.top;
//通过比例尺的反函数计算原数据中的值，例如x0为某个年份，y0为GDP值
var x0 = xScale.invert(mouseX);
var y0 = yScale.invert(mouseY);
//对x0四舍五入，如果x0是2005.6，则返回2006；如果是2005.2，则返回2005
x0 = Math.round(x0);
//查找在原数组中x0的值，并返回索引号
var bisect = d3.bisector(function (d) {
return d[0];
}).left;
var index = bisect(data, x0);
//获取年份和gdp数据
var year = x0;
var gdp = [];
for (var k = 0; k < dataset.length; k++) {
gdp[k] = {
country : dataset[k].country,
value : dataset[k].gdp[index][1]
};
}
//设置提示框的标题文字（年份）
title.html("<strong>" + year + "年</strong>");
//设置颜色标记的颜色
desColor.style("background-color", function (d, i) {
return colors[i];
});
//设置描述文字的内容
desText.html(function (d, i) {
return gdp[i].country + "\t" + "<strong>" + gdp[i].value + "</strong>";
});
//设置提示框的位置
tooltip.style("left", (d3.event.pageX) + "px")
.style("top", (d3.event.pageY + 20) + "px");
//获取垂直对齐线的x坐标
var vlx = xScale(data[index][0]) + padding.left;
//设定垂直对齐线的起点和终点
vLine.attr("x1", vlx)
.attr("y1", padding.top)
.attr("x2", vlx)
.attr("y2", height - padding.bottom);
}
var markStep = 80;
var gMark = svg.selectAll(".gMark")
.data(dataset)
.enter()
.append("g")
.attr("transform", function (d, i) {
return "translate(" + (padding.left + i * markStep) + "," + (height - padding.bottom + 40) + ")";
});
gMark.append("rect")
.attr("x", 0)
.attr("y", 0)
.attr("width", 10)
.attr("height", 10)
.attr("fill", function (d, i) {
return colors[i];
});
gMark.append("text")
.attr("dx", 15)
.attr("dy", ".5em")
.attr("fill", "black")
.text(function (d) {
return d.country;
});
//x轴
var xAxis = d3.svg.axis()
.scale(xScale)
.ticks(5)
.tickFormat(d3.format("d"))
.orient("bottom");
//y轴
var yAxis = d3.svg.axis()
.scale(yScale)
.orient("left");
svg.append("g")
.attr("class", "axis")
.attr("transform", "translate(" + padding.left + "," + (height - padding.bottom) + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.attr("transform", "translate(" + padding.left + "," + padding.top + ")")
.call(yAxis);
function updateLineChart() {
this.update = function (updateData) {
//xScale.domain(updateData,function(d){return d.name});
var numValues = updateData.length;
var updategdpmax = 0;
for (var i = 0; i < updateData.length; i++) {
var currGdp = d3.max(updateData[i].gdp, function (d) {
return d[1];
});
if (currGdp > updategdpmax)
updategdpmax = currGdp;
}
yScale = d3.scale.linear()
.domain([0, updategdpmax * 1.1])
.range([height - padding.top - padding.bottom, 0]);
yAxis = d3.svg.axis()
.scale(yScale)
.orient("left");
svg.selectAll("g.y.axis")
.call(yAxis);
svg.selectAll("path") //选择<svg>中所有的<path>
.data(updateData) //绑定数据
.transition()
.duration(2000)
.ease("linear")
.attr("d", function (d) {
return linePath(d.gdp); //返回直线生成器得到的路径
});
}
}
return new updateLineChart();
}
刚开始数据刷新了但是坐标轴木有刷新
引入
svg.selectAll("g.y.axis")
.call(yAxis);
以上就是d3.js实现实时刷新折线图的全部内容，希望给大家学习d3.js带来帮助。