我目前正在尝试创建一个表示数据并能够根据选择进行更改的条形图，但条形图很难阅读并且难以理解数据。我正在尝试制作一个工具提示，显示每个项目使用的资源数量。这是到目前为止我的代码:
<!DOCTYPE html>
<html>
<head>
<meta>
<meta http-equiv="refresh" content="90">
<meta name="description" content="Drawing Shapes w/ D3 - BarChart" />
<meta charset="utf-8">
<title>Resources per Project</title>
<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>
<style type="text/css">
h1 {
font-size: 35px;
color: darkgrey;
font-family: Helvetica;
border-bottom-width: 3px;
border-bottom-style: dashed;
border-bottom-color: black;
}
h2 {
font-size: 20px;
color: black;
font-family: Helvetica;
text-decoration: underline;
margin-left: 350px;
margin-top: 2px;
}
</style>
</head>
<body>
<h1>Resources used per Project</h1>
<p>Choose Month:
<select id="label-option">
<option value="April">April</option>
<option value="May">May</option>
<option value="June">June</option>
<option value="July">July</option>
<option value="August">August</option>
<option value="September">September</option>
</select>
<script type="text/javascript">
var width = 800
var height = 500
var emptyVar = 0
var dataArrayProjects = ['2G', 'An', 'At', 'Au', 'AW', 'Ch', 'CI', 'CN']
var April = [0.35, 1.66, 3.04, 1.54, 3.45, 2.56, 2.29, 1.37]
var May = [0.36, 1.69, 3.08, 1.54, 3.62, 2.61, 2.22, 1.44]
var June = [0.34, 1.7, 3.08, 1.63, 3.66, 2.68, 2.24, 1.51]
var July = [0.3, 1.72, 3.17, 1.67, 3.56, 2.56, 2.17, 1.44]
var August = [0.28, 1.79, 3.18, 1.71, 3.62, 2.73, 2.26, 1.54]
var September = [1.23, 1.74, 3.12, 1.61, 3.66, 2.71, 2.2, 1.48]
var widthScale = d3.scale.linear()
.domain([0, 4])
.range([0, width - 60]);
d3.select("#label-option").on("change", change)
function change() {
var data = April;
if (this.selectedIndex == 1){
data = May;
} else if (this.selectedIndex == 2){
data = June;
} else if (this.selectedIndex == 3){
data = July;
} else if (this.selectedIndex == 4){
data = August;
} else if (this.selectedIndex == 5){
data = September;
}
canvas.selectAll("rect")
.data(data)
.attr("width", emptyVar)
.attr("height", 50)
.attr("fill", function(d) {
return color(d)
})
.attr("y", function(d, i) {
return i * 55
})
bars.transition()
.duration(1500)
.delay(200)
.attr("width", function(d) {
return widthScale(d);
})
}
var heightScale = d3.scale.ordinal()
.domain(dataArrayProjects)
.rangePoints([10, height - 85]);
var color = d3.scale.linear()
.domain([0, 4])
.range(["#000066", "#22abff"])
var axis = d3.svg.axis()
.ticks("10")
.scale(widthScale);
var yAxis = d3.svg.axis()
.scale(heightScale)
.orient("left");
var canvas = d3.select("body")
.append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(40, 0)");
var bars = canvas.selectAll("rect")
.data(April)
.enter()
.append("rect")
.attr("width", emptyVar)
.attr("height", 50)
.attr("fill", function(d) {
return color(d)
})
.attr("y", function(d, i) {
return i * 55
})
canvas.append("g")
.attr("transform", "translate(0, 430)")
.attr("font-family", "Helvetica")
.attr("font-size", "15px")
.call(axis);
canvas.append("g")
.attr("font-family", "Helvetica")
.attr("font-size", "15px")
.style("fill", "black")
.attr("class", "y axis")
.call(yAxis);
bars.transition()
.duration(1500)
.delay(200)
.attr("width", function(d) {
return widthScale(d);
})
var yAxisLine = canvas.append("line")
.attr("x1", -3)
.attr("y1", 0)
.attr("x2", -3)
.attr("y2", 436)
.attr("stroke-width", 6)
.attr("stroke", "black");
</script>
<h2>Resources</h2>
</body>
</html>如何添加工具提示，以便当您将鼠标悬停在其中一个栏上时，显示它代表的数据编号。
最佳答案
有一些可用的插件，如 @mbox 建议 foxToolTip和 d3-tip等等
这里我没有使用任何插件，使用CSS和JS来创建它 CSS
#myTooltip {
position: absolute;
text-align: left;
width: 80px;
height: auto;
min-height: 20px;
padding: 2px;
font: 12px sans-serif;
background-color: rgb(255, 255, 255);
border: 2px solid rgb(100, 161, 209);
color: #5E99BD;
border-radius: 8px 8px 8px 8px;
pointer-events: none;
padding: 11px;
}
#myTooltip:before {
box-sizing: border-box;
display: inline;
font-size: 18px;
width: 100%;
line-height: 1;
color: rgb(100, 161, 209);
content: "\25BC";
position: absolute;
text-align: center;
top: 100%;
left: -2px;
}
JS
您必须添加一个代表工具提示的 div。
var tooplTipDiv = d3.select("body").append("div")
.attr("id", "myTooltip")
.style("opacity", 0);
并且您应该为mouseover和mouseout提供回调
var bars = canvas.selectAll("rect")
.data(April)
.enter()
.append("rect")
//add callbacks for onMouseOver and onMouseOut
.on("mouseover", onMouseOver)
.on("mouseout", onMouseOut)
.attr("width", emptyVar)
.attr("height", 50)
.attr("fill", function(d) {
return color(d)
})
.attr("y", function(d, i) {
return i * 55
})
以及mouseover和mouseout的函数
function onMouseOver(d){
var tooltipDiv = d3.select("#myTooltip");
tooltipDiv.transition()
.duration(200)
.style("opacity", 1);
tooltipDiv.html( "your Content")
.style("left", (parseFloat(widthScale(d))) + "px")
.style("cursor", "pointer")
.style("top", function(d){
return d3.event.pageY - this.offsetHeight - 17 + "px"
})
.style("color", "#333333");
}
function onMouseOut(d){
var tooltipDiv = d3.select("#myTooltip");
tooltipDiv.transition()
.duration(500)
.style("opacity", 0);
}
如果您仍然有一些困惑，请告诉我，我将发布完整的工作代码。
关于javascript - 如何向 d3 条形图添加工具提示？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38065551/