移動Web開發(fā)必備基礎（flex容器屬性）

精品唯居 2021-11-14

展開全文

box-sizing

在pc端一般使用默認值 content-box

在移動端一般使用 border-box

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <style>
        .parent{width:100%;}
        .child{width:50%;height:30px;float:left;}
        .parent .child{background-color: pink;border:1px solid #333;box-sizing:content-box;}
        .parent2 .child{background-color: #abcdef;border:1px solid #333;box-sizing:border-box;}
    </style>
</head>
<body>
    <div class="parent">
        <div class="child"></div>
        <div class="child"></div>
    </div>
    <div class="parent2">
        <div class="child"></div>
        <div class="child"></div>
    </div>
    <script>

    </script>
</body>
</html>

移動端通用寫法：

*{margin:0;padding:0;box-sizing:border-box;}

圖標字體：

阿里巴巴矢量圖標庫 https://www./

選中圖標后添加至項目，然后下載至本地

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .iconfont{font-size:30px;}
        .icon-gouwuche{color:rgb(234,58,67);}
        .icon-file{color:rgb(244,189,0);}
        .icon-saomiao{color:rgb(42,83,205)}
        .icon-xialajiantou{color:rgb(85,85,85);}
    </style>
</head>
<body>
    <div class="parent">
        <i class="iconfont icon-gouwuche"></i>
        <i class="iconfont icon-file"></i>
        <i class="iconfont icon-saomiao"></i>
        <i class="iconfont icon-xialajiantou"></i>
    </div>
    </div>
    <script>

    </script>
</body>
</html>

flex布局

彈性布局彈性盒子布局

flex容器(flex container)：父元素 display:flex | inline-flex;

flex項目(flex item)：子元素（不包括孫子元素）

flex容器的屬性：

div元素默認是塊元素，垂直排列

使用flex或者inline-flex布局之后，會自動水平排列

在沒有設置容器寬度的情況下，flex的寬度是100%，而inline-flex的寬度取決于項目總寬度

在設置容器寬度的情況下，二者的容器寬度相同

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;}
        .parent1{display: flex;}
        .parent2{display: inline-flex;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
    </div>
    <div class="parent parent2">
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
    </div>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;width:100%;}
        .parent1{display: flex;}
        .parent2{display: inline-flex;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
    </div>
    <div class="parent parent2">
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
    </div>

</body>
</html>

flex-direction 決定主軸方向

row 默認水平軸為主軸，左邊開始右邊結束

row-reverse 水平軸為主軸，右邊開始左邊結束

column 垂直軸為主軸，上邊開始下邊結束

column-reverse 垂直軸為主軸，下邊開始上邊結束

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;display: flex;}
        .parent1{flex-direction:row;}
        .parent2{flex-direction:row-reverse;}
        .parent3{flex-direction:column;}
        .parent4{flex-direction:column-reverse;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent2">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent3">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent4">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>

</body>
</html>

flex-wrap 一行排不下時是否換行

nowrap 不換行，進行壓縮（默認值）

wrap 換行

wrap-reverse 換行的排在前面

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;display: flex;}
        .parent1{flex-wrap:nowrap;}
        .parent2{flex-wrap:wrap;}
        .parent3{flex-wrap:wrap-reverse;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
        <div class="child">9</div>
        <div class="child">10</div>
        <div class="child">11</div>
        <div class="child">12</div>
    </div>
    <div class="parent parent2">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
        <div class="child">9</div>
        <div class="child">10</div>
        <div class="child">11</div>
        <div class="child">12</div>
    </div>
    <div class="parent parent3">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
        <div class="child">9</div>
        <div class="child">10</div>
        <div class="child">11</div>
        <div class="child">12</div>
    </div>

</body>
</html>

flex-flow 是flex-direction和flex-wrap的簡寫

如：flex-flow:row wrap;

justify-content 項目在主軸上的對齊方式

flex-start 整體左對齊

flex-end 整體右對齊

center 整體居中對齊

space-between 兩端對齊

space-around 每個項目的左右間距相等（項目之間的間距是項目與邊框的間距的2倍）

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;display: flex;}
        .parent1{justify-content:flex-start;}
        .parent2{justify-content:flex-end;}
        .parent3{justify-content:center;}
        .parent4{justify-content:space-between;}
        .parent5{justify-content:space-around;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent2">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent3">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent4">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent5">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>

</body>
</html>

align-items 在交叉軸上的排列方式

flex-start 上邊對齊

flex-end 下邊對齊

center 居中對齊

baseline 基線對齊

stretch 默認值，如果項目沒有設置高度，或者高度設置為auto，則默認占滿整個容器

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;display: flex;}
        .parent .child:nth-child(even){height:130px;}
        .parent1{align-items:flex-start;}
        .parent2{align-items:flex-end;}
        .parent3{align-items:center;}
        .parent4{align-items:baseline;}
        .parent5 .child{height:auto;}
        .parent5{align-items:stretch;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent2">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent3">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent4">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>
    <div class="parent parent5">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
    </div>

</body>
</html>

align-content 交叉軸的對齊方式（針對多行，如果單行是不起作用的）

將所有項目看成一個整體

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        .child{width:100px;height:100px;background:orange;border:1px solid #333;margin:2px;}
        .parent{background:#abcdef;display: flex;flex-wrap:wrap;height:300px;border:1px solid;}
        .parent1{align-content:flex-start;}
        .parent2{align-content:flex-end;}
        .parent3{align-content:center;}
        .parent4{align-content:space-between;}
        .parent5{align-content:space-around;}
        .parent6 .child{height:auto;}
        .parent6{align-content:stretch;}
    </style>
</head>
<body>
    <div class="parent parent1">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>
    <div class="parent parent2">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>
    <div class="parent parent3">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>
    <div class="parent parent4">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>
    <div class="parent parent5">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>
    <div class="parent parent6">
        <div class="child">1</div>
        <div class="child">2</div>
        <div class="child">3</div>
        <div class="child">4</div>
        <div class="child">5</div>
        <div class="child">6</div>
        <div class="child">7</div>
        <div class="child">8</div>
    </div>

</body>
</html>