1.HTML

这部分比较简单，四个div加两个button搞定

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1.0" />
    <link rel="stylesheet" href="style.css">
    <title>MyProgressSteps</title>
</head>
<body>
    <div class="container">
        <div class="progress-container">
            <div class="progress" id="progress"></div>
            <div class="circle active">1</div>
            <div class="circle">2</div>
            <div class="circle">3</div>
            <div class="circle">4</div>
        </div>

        <button class="btn" id="prev" disabled>Prev</button>
        <button class="btn" id="next">Next</button>
    </div>
    <script src="script.js"></script>
</body>
</html>

2.CSS

其中进度条的线实现思路是先画一条灰色的线，然后再画一条蓝色的线，通过控制蓝色线的长度来实现精度条显示。

@import url('https://fonts.googleapis.com/css?family=Muli&display=swap');

:root{
    --line-border-fill: #3498db;
    --line-border-empty: #e0e0e0;
}

* {
    box-sizing: border-box;
}

body {
    background-color: #f6f7fb;
    font-family: 'Muli', sans-serif;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    overflow: hidden;
    margin: 0;
}

.container {
    text-align: center;
}

.progress-container {
    display: flex;
    justify-content: space-between;
    position: relative;
    margin-bottom: 30px;
    max-width: 100%;
    width: 350px;
}
/*伪类选择器,在progress-container类前插入内容*/
.progress-container::before {
    content: '';
    background-color: var(--line-border-empty);
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    height: 4px;
    width: 100%;
    z-index: -1;
}

.progress {
    background-color: var(--line-border-fill);
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    height: 4px;
    width: 0%;
    z-index: -1;
    transition: 0.4s ease;
}

.circle {
    background-color: #fff;
    color: #999;
    border-radius: 50%;
    height: 30px;
    width: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 3px solid var(--line-border-empty);
    transition: 0.4s ease;
}

.circle.active {
    border-color: var(--line-border-fill);
}

.btn {
    background-color: var(--line-border-fill);
    color: #fff;
    border: 0;
    border-radius: 6px;
    cursor: pointer;
    font-family: inherit;
    padding: 8px 30px;
    margin: 5px;
    font-size: 14px;
}

.btn:active {
    transform: scale(0.98);
}
.btn:focus {
    outline: 0;
}

.btn:disabled {
    background-color: var(--line-border-empty);
    cursor: not-allowed;
}

3.JS

js控制进度条的长度以及按钮active属性的增/删

const progress = document.getElementById('progress')
const prev = document.getElementById('prev')
const next = document.getElementById('next')
const circles = document.querySelectorAll('.circle')

let currentActive = 1

next.addEventListener('click',()=>{
    currentActive++

    if(currentActive > circles.length) {
        currentActive = circles.length
    }

    update()
})

prev.addEventListener('click', () => {
    currentActive--

    if(currentActive < 1) {
        currentActive = 1
    }

    update()
})

function update() {
    circles.forEach((circle,idx) =>{
        if(idx < currentActive) {
            circle.classList.add('active')
        } else {
            circle.classList.remove('active')
        }
    })
    const actives = document.querySelectorAll('.active')

    progress.style.width = (actives.length - 1) / (circles.length - 1) * 100 + '%'

    if(currentActive === 1) {
        prev.disabled = true
    } else if(currentActive === circles.length) {
        next.disabled = true
    } else {
        prev.disabled = false
        next.disabled = false
    }
}

50天50个前端页面练习Day2：进度条

1.HTML

2.CSS

3.JS