步骤计数器 

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title></title>
        <link rel="stylesheet" href="new_file.css">
    </head>
    <body>
        <div class="box">
            <div class="progress">
                <div class="hui"></div>
                <div class="lan"></div>
                <div class="step active">1</div>
                <div class="step">2</div>
                <div class="step">3</div>
                <div class="step">4</div>
            </div>
            <div class="btn">
                <button type="button" class="prev" disabled>上一个</button>
                <button type="button" class="next">下一个</button>
            </div>
        </div>
        <script src="new_file.js"></script>
    </body>
</html>

*{
    margin: 0;
    padding: 0;
}
/* 让元素在网页居中 */
body{
    background-color: yellow;
    height: 100vh;
    /* 弹性布局 */
    display: flex;
    justify-content: center;
    align-items: center;
}
/* 整个计数器区域 */
.box{
    /* background-color: greenyellow; */
    /* 弹性布局 */
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}
.progress{
    width: 350px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-direction: row;
    position: relative;
}
.hui{
    position: absolute;
    width: 100%;
    height: 5px;
    background-color: lightgray;
    z-index: -2;
}
.lan{
    position: absolute;
    width: 50px;
    height: 5px;
    background-color: deepskyblue;
    z-index: -1;
    transition: all 0.5s;
}
.step{
    width: 40px;
    height: 40px;
    border: 5px solid lightgray;
    border-radius: 25px;
    background-color: white;
    text-align: center;
    line-height: 40px;
    transition: all 0.5s;
}
.step.active{
    border-color: deepskyblue;
}
.btn{
    margin-top: 30px;
}
button{
    margin: 30px;
    padding: 5px 20px;
    transition: all 0.5s;
    background-color: deepskyblue;
}
/* 点击按钮时的动画 */
button:not(:disabled):active{
    transform: scale(0.8);
}
/* 禁用按钮的样子 */
button:disabled{
    background-color: lightgray;
    color: white;
    cursor: not-allowed;
}

// 上一个 和 下一个 按钮
let prev = document.querySelector('.prev')
let next = document.querySelector('.next')
// 选择 1234..
let steps = document.querySelectorAll('.step')
// 选择 lan 条
let lan = document.querySelector('.lan')
// 选择 进度条（为了重新计算宽度）
let progress = document.querySelector('.progress')
// 创建 计数器 
let i = 1

// 根据步骤数计算新宽度
progress.style.width = (steps.length*2-1)*50+'px'

// 点击下一个触发事件
next.onclick = function(){
    i = i+1
    // steps.length是步骤的数量
    if (i>steps.length){
        i = steps.length
    }
    // 把对应步骤数的边框变蓝
    steps[i-1].classList.add('active')
    // 当步骤超过1时，解除上一个按钮的禁用
    if (i>1){
        prev.disabled = false
    }
    // 当步骤数到达最大
    if (i===steps.length){
        next.disabled = true
    }
    // 增加蓝线
    lan.style.width = (i-1)*100 + 'px'
} 


// 点击上一个 按钮 触发的事件
prev.onclick = function(){
    i = i-1
    if (i<1){
        i = 1
    }
    // 删除上一个步骤的active
    steps[i].classList.remove('active')
    // 
    if (i<steps.length){
        next.disabled = false
    }
    if (i===1){
        prev.disabled = true
    }
    // 减短蓝线
    lan.style.width = (i-1)*100 + 'px'
}
posted @ 2023-03-18 19:17  不尽人意的K  阅读(11)  评论(0)  编辑  收藏  举报