js05 - Flex Panel Gallery
戚奇略
内容
针对CSS学习flex部分
#### 针对 Flex items 的特性（Children）
- `flex-growth`：伸展值
- `flex-shrink`：可接受的压缩值
- `flex-basis`：元素默认的尺寸值
- `flex`：以上三个值按顺序的缩写
#### 针对 Flex container 的特性（Parent）
- `display: flex`：将这个元素设置成弹性盒子
- `flex-direction`：主轴方向
- `row`：横向
- `column`：纵向
- `justify-content`：沿主轴的的对齐方式
- `align-items`：沿侧轴的对齐方式
- `align-content`：子元素中文本沿侧轴的对齐方式（只有一行时无效）
通过js获取标签以后将特定的panel`flex`大小进行改变，从而改变panel占位大小
由于每个panel中含有3个p标签,所以可以用:first-child以及:last-child进行控制第1及第3个p标签
.panel > *:first-child{
//使第一个p标签元素沿Y轴向上移动100%,即为-100%,平移出屏幕
transform: translateY(-100%)
}
.panel.open-active > *:first-child{
//使第一个p标签元素沿Y轴向下移动100%,即为返回0,平移回屏幕原位置
transform: translateY(0)
}
//同理可得
.panel > *:last-child{
transform: translateY(100%)
}
.panel.open-active > *:last-child{
transform: translateY(0)
}
针对JS部分
this.classList.toggle()
这个方法可以给dom元素添加类，消除类。点击行为，转换。
通过click事件给相关的dom元素特定的panel添加事件
//设定方法函数,令toggleOpen函数为转换dom元素类
function toggleOpen(){
this.classList.toggle('open')
}
//定义panels,从dom中获取
const panels = document.querySeletorAll('.panel')
//forEach遍历panels,给所有的panels加上click事件,方法为toggleOpen()
panels.forEach(panel => panel.addEventListener('click',toggleOpen))
//给文字添加变换
function toggleActive(e){
//获取值名
console.log(e.propertyName);
//形变由于flex-grow,故当值名含有flex时进行添加类
if(e.propertyName.includes('flex')){
console.log(e.propertyName);
//添加open-active类
this.classList.toggle('open-active')
}
}
//forEach遍历panels,给所有的panel加上transitionend事件,方法为toggleActive
panels.forEach(panel => panel.addEventListener('transitionend',toggleActive))
源start文件代码(取自github JavaScript 30 - 05 )
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Flex Panels </title>
<link href='https://fonts.googleapis.com/css?family=Amatic+SC' rel='stylesheet' type='text/css'>
</head>
<body>
<style>
html {
box-sizing: border-box;
background: #ffc600;
font-family: 'helvetica neue';
font-size: 20px;
font-weight: 200;
}
body {
margin: 0;
}
*, *:before, *:after {
box-sizing: inherit;
}
.panels {
min-height: 100vh;
overflow: hidden;
}
.panel {
background: #6B0F9C;
box-shadow: inset 0 0 0 5px rgba(255,255,255,0.1);
color: white;
text-align: center;
align-items: center;
/* Safari transitionend event.propertyName === flex */
/* Chrome + FF transitionend event.propertyName === flex-grow */
transition:
font-size 0.7s cubic-bezier(0.61,-0.19, 0.7,-0.11),
flex 0.7s cubic-bezier(0.61,-0.19, 0.7,-0.11),
background 0.2s;
font-size: 20px;
background-size: cover;
background-position: center;
}
.panel1 { background-image:url(https://source.unsplash.com/gYl-UtwNg_I/1500x1500); }
.panel2 { background-image:url(https://source.unsplash.com/rFKUFzjPYiQ/1500x1500); }
.panel3 { background-image:url(https://images.unsplash.com/photo-1465188162913-8fb5709d6d57?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&w=1500&h=1500&fit=crop&s=967e8a713a4e395260793fc8c802901d); }
.panel4 { background-image:url(https://source.unsplash.com/ITjiVXcwVng/1500x1500); }
.panel5 { background-image:url(https://source.unsplash.com/3MNzGlQM7qs/1500x1500); }
/* Flex Children */
.panel > * {
margin: 0;
width: 100%;
transition: transform 0.5s;
}
.panel p {
text-transform: uppercase;
font-family: 'Amatic SC', cursive;
text-shadow: 0 0 4px rgba(0, 0, 0, 0.72), 0 0 14px rgba(0, 0, 0, 0.45);
font-size: 2em;
}
.panel p:nth-child(2) {
font-size: 4em;
}
.panel.open {
font-size: 40px;
}
</style>
<div class="panels">
<div class="panel panel1">
<p>Hey</p>
<p>Let's</p>
<p>Dance</p>
</div>
<div class="panel panel2">
<p>Give</p>
<p>Take</p>
<p>Receive</p>
</div>
<div class="panel panel3">
<p>Experience</p>
<p>It</p>
<p>Today</p>
</div>
<div class="panel panel4">
<p>Give</p>
<p>All</p>
<p>You can</p>
</div>
<div class="panel panel5">
<p>Life</p>
<p>In</p>
<p>Motion</p>
</div>
</div>
<script>
</script>
</body>
</html>
完成
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Flex Panels </title>
<link href='https://fonts.googleapis.com/css?family=Amatic+SC' rel='stylesheet' type='text/css'>
</head>
<body>
<style>
html {
box-sizing: border-box;
background:#ffc600;
font-family:'helvetica neue';
font-size: 20px;
font-weight: 200;
}
body {
margin: 0;
}
*, *:before, *:after {
box-sizing: inherit;
}
.panels {
min-height:100vh;
overflow: hidden;
display: flex;
}
.panel {
background:#6B0F9C;
box-shadow:inset 0 0 0 5px rgba(255,255,255,0.1);
color:white;
text-align: center;
align-items:center;
/* Safari transitionend event.propertyName === flex */
/* Chrome + FF transitionend event.propertyName === flex-grow */
transition:
font-size 0.7s cubic-bezier(0.61,-0.19, 0.7,-0.11),
flex 0.7s cubic-bezier(0.61,-0.19, 0.7,-0.11),
background 0.2s;
font-size: 20px;
background-size:cover;
background-position:center;
flex: 1;
display: flex;
flex-direction: column;
justify-content: center;
align-items: center;
}
.panel1 { background-image:url(https://source.unsplash.com/gYl-UtwNg_I/1500x1500); }
.panel2 { background-image:url(https://source.unsplash.com/1CD3fd8kHnE/1500x1500); }
.panel3 { background-image:url(https://images.unsplash.com/photo-1465188162913-8fb5709d6d57?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&w=1500&h=1500&fit=crop&s=967e8a713a4e395260793fc8c802901d); }
.panel4 { background-image:url(https://source.unsplash.com/ITjiVXcwVng/1500x1500); }
.panel5 { background-image:url(https://source.unsplash.com/3MNzGlQM7qs/1500x1500); }
.panel > * {
margin:0;
width: 100%;
transition:transform 0.5s;
flex: 1 0 auto;
display: flex;
justify-content: center;
align-items: center;
}
.panel > *:first-child{transform: translateY(-100%);}
.panel.open-active > *:first-child{transform: translateY(0);}
.panel > *:last-child{transform: translateY(100%);}
.panel.open-active > *:last-child{transform: translateY(0);}
.panel p {
text-transform: uppercase;
font-family: 'Amatic SC', cursive;
text-shadow:0 0 4px rgba(0, 0, 0, 0.72), 0 0 14px rgba(0, 0, 0, 0.45);
font-size: 2em;
}
.panel p:nth-child(2) {
font-size: 4em;
}
.panel.open {
flex: 5;
font-size:40px;
}
.cta {
color:white;
text-decoration: none;
}
</style>
<div class="panels">
<div class="panel panel1">
<p>Hey</p>
<p>Let's</p>
<p>Dance</p>
</div>
<div class="panel panel2">
<p>Give</p>
<p>Take</p>
<p>Receive</p>
</div>
<div class="panel panel3">
<p>Experience</p>
<p>It</p>
<p>Today</p>
</div>
<div class="panel panel4">
<p>Give</p>
<p>All</p>
<p>You can</p>
</div>
<div class="panel panel5">
<p>Life</p>
<p>In</p>
<p>Motion</p>
</div>
</div>
<script>
const panels = document.querySelectorAll('.panel')
function toggleOpen(){
this.classList.toggle('open')
}
function toggleActive(e){
if(e.propertyName.includes('flex')){
console.log(e.propertyName)
this.classList.toggle('open-active')
}
}
panels.forEach(panel => panel.addEventListener('click',toggleOpen));
panels.forEach(panel => panel.addEventListener('transitionend',toggleActive))
</script>
</body>
</html>
问题
快速双击图片时出现字体位置发生变化与图片不统一进行动画
.panel > *{
//根据图片flex格局变化时最长时间0.7s取值,给文字动画效果延迟
//即当图片动画完毕后=>进行文字动画
transition: transform 0.7s 0.7s
}
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