D3.js 柱形图数据动态更新

Jiafeng 2022-10-30 11:50:13
分类： D3 418 0
一、前言

使用d3做个带交互的柱状图，通过改变select选项，图表相应变化
D3.js相关参考资料：https://zjiafeng.github.io/d3-demo/D3.pdf
二、开发

在线访问地址：https://zjiafeng.github.io/d3-demo/bar/index.html
代码如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<script src="https://d3js.org/d3.v6.min.js"></script>
</head>
<style>
.priceXAxis path {
    stroke: #FE5F64;
    stroke-width: 0px;
}

.priceXAxis line {
    stroke: #FE5F64;
    stroke-width: 0px;
}

.priceXAxis text {
    fill: #FE5F64;
    font-size: 10px;
}

.priceYAxis text {
    fill: #FE5F64;
    font-size: 12px;
}

.priceYAxis line {
    stroke: #FE5F64;
    stroke-width: 0px;
}

.priceYAxis path {
    stroke: #FE5F64;
    stroke-width: 2.5px;
}

.grid line {
    stroke: #FE5F64;
    stroke-opacity: 0.7;
}

.grid path {
    stroke-width: 0;
}
</style>
<body>
<div id="chart"></div>
</body>
<script>
// set the dimensions and margins of the graph
const margin = { top: 50, right: 30, bottom: 50, left: 90 },
    width = 1000 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// append the svg object to the body of the page
const svg = d3.select("#chart")
    .append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
    .append("g")
    .attr("transform", `translate(${margin.left}, ${margin.top})`);

/**
 * data 图表数据
 * flag 1/首次渲染   0/更新
 * */
const drawXY = (data, flag) => {
    // X axis
    d3.select(".priceXAxis").remove();
    d3.select(".grid").remove();

    const x = d3.scaleLinear()
        .domain([0, d3.max(data.map(item => item.value * 1))])
        .range([0, width]);
    svg.append("g")
        .attr("class", "priceXAxis")
        .attr("transform", `translate(0, ${height})`)
        .call(d3.axisBottom(x))

    // gridlines in x axis function
    function make_x_gridlines() {
        return d3.axisBottom(x)
            .ticks(10)
    }

    // add the X gridlines
    svg.append("g")
        .attr("class", "grid")
        .attr("transform", "translate(0," + height + ")")
        .style("stroke-width", "1px")
        .style("stroke-dasharray", 2)
        .call(make_x_gridlines()
            .tickSize(-height)
            .tickFormat("")
        )

    if (flag) {
        // Y axis
        const y = d3.scaleBand()
            .range([0, height])
            .domain(data.map(d => d.key))
            .padding(.2);
        svg.append("g")
            .attr("class", "priceYAxis")
            .attr("transform", "translate(0, 0)")
            .call(d3.axisLeft(y))
        svg.selectAll('rect')
            .data(data).enter()
            .append('rect')
            .transition()
            .duration(1000)
            .ease(d3.easeLinear)
            .attr("x", x(0.2))
            .attr("y", d => y(d.key))
            .attr("width", d => x(d.value))
            .attr("height", y.bandwidth() / 1.2)
            .attr("fill", "#69b3a2")
    } else {
        svg.selectAll("rect")     // select rects to be updated
            .data(data)            // New data binded to rects
            .transition()
            .duration(1000)
            .ease(d3.easeLinear)
            .attr("width", d => x(d.value)) // visual attribute to be updated
    }
}

//Reading the data from the CSV file
d3.csv('airbnbTop10Suburbs.csv').then(jsonData => {
    let data = jsonData.map(item => {
        return { key: item.neighbourhood, value: item['All'] }
    })
    drawXY(data, 1)
});

//set the choices for buttons on the dropdown menue
var allGroup = ["All", "OneToFour", "FiveToEight", "MoreThanNine"]

// Initialize the button
var dropdownButton = d3.select("#chart")
    .append('select')

dropdownButton // Add a button
    .selectAll('myOptions') // Next 4 lines add 6 options = 6 colors
    .data(allGroup)
    .enter()
    .append('option')
    .text(function (d) { return d; }) // text showed in the menu
    .attr("value", function (d) { return d; }) // corresponding value returned by the button

// When the button is changed, run the updateChart function
dropdownButton.on("change", async function (d) {
    // recover the option that has been chosen
    let selectedOption = d3.select(this).property("value")
    selectedOption = selectedOption === 'FiveToEight' ? '5-8cap' : selectedOption
    let jsonData = await d3.csv("./airbnbTop10Suburbs.csv")
    let data = jsonData.map(item => {
        return { key: item.neighbourhood, value: item[selectedOption] }
    })
    drawXY(data, 0)
})
</script>
</html>
D3.js 柱形图数据动态更新

一、前言

二、开发

共 0 条评论关于 “D3.js 柱形图数据动态更新”
