CSS3动画(重要)
CSS3 动画
CSS3,我们可以创建动画,它可以取代许多网页动画图像,Flash动画,和JAVAScripts。
CSS3 @keyframes 规则
要创建CSS3动画,你将不得不了解@keyframes规则。
@keyframes规则是创建动画。 @keyframes规则内指定一个CSS样式和动画将逐步从目前的样式更改为新的样式。
实例:
@keyframes myfirst
{
from {background: red;}
to {background: yellow;}
}
@-webkit-keyframes myfirst /* Safari 与 Chrome */
{
from {background: red;}
to {background: yellow;}
}
CSS3 动画
当在 @keyframes 创建动画,把它绑定到一个选择器,否则动画不会有任何效果。
指定至少这两个CSS3的动画属性绑定向一个选择器:
- 规定动画的名称
- 规定动画的时长
例子: 把 "myfirst" 动画捆绑到 div 元素,时长:5 秒:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> div { width:100px; height:100px; background:red; animation:myfirst 5s; -webkit-animation:myfirst 5s; /* Safari and Chrome */ } @keyframes myfirst { from {background:red;} to {background:yellow;} } @-webkit-keyframes myfirst /* Safari and Chrome */ { from {background:red;} to {background:yellow;} } </style> </head> <body> <p><b>注意:</b> 该实例在 Internet Explorer 9 及更早 IE 版本是无效的。</p> <div></div> </body> </html>
注意: 您必须定义动画的名称和动画的持续时间。如果省略的持续时间,动画将无法运行,因为默认值是0。
CSS3动画是什么?
动画是使元素从一种样式逐渐变化为另一种样式的效果。
您可以改变任意多的样式任意多的次数。
请用百分比来规定变化发生的时间,或用关键词 "from" 和 "to",等同于 0% 和 100%。
0% 是动画的开始,100% 是动画的完成。
为了得到最佳的浏览器支持,您应该始终定义 0% 和 100% 选择器。
例子: 当动画为 25% 及 50% 时改变背景色,然后当动画 100% 完成时再次改变:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> div { width:100px; height:100px; background:red; animation:myfirst 5s; -moz-animation:myfirst 5s; /* Firefox */ -webkit-animation:myfirst 5s; /* Safari and Chrome */ -o-animation:myfirst 5s; /* Opera */ } @keyframes myfirst { 0% {background:red;} 25% {background:yellow;} 50% {background:blue;} 100% {background:green;} } @-moz-keyframes myfirst /* Firefox */ { 0% {background:red;} 25% {background:yellow;} 50% {background:blue;} 100% {background:green;} } @-webkit-keyframes myfirst /* Safari and Chrome */ { 0% {background:red;} 25% {background:yellow;} 50% {background:blue;} 100% {background:green;} } @-o-keyframes myfirst /* Opera */ { 0% {background:red;} 25% {background:yellow;} 50% {background:blue;} 100% {background:green;} } </style> </head> <body> <div></div> <p><b>注释:</b>当动画完成时,会变回初始的样式。</p> <p><b>注意:</b> 该实例在 Internet Explorer 9 及更早 IE 版本是无效的。</p> </body> </html>
改变背景色和位置:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> div { width:100px; height:100px; background:red; position:relative; animation:myfirst 5s; -webkit-animation:myfirst 5s; /* Safari and Chrome */ } @keyframes myfirst { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } @-webkit-keyframes myfirst /* Safari and Chrome */ { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } </style> </head> <body> <p><b>注意:</b> 该实例在 Internet Explorer 9 及更早 IE 版本是无效的。</p> <div></div> </body> </html>
运行myfirst动画,设置所有的属性:(用法一) 先定义动画,然后绑定到元素。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> div { width:100px; height:100px; background:red; position:relative; animation-name:myfirst; animation-duration:5s; animation-timing-function:linear; animation-delay:2s; animation-iteration-count:infinite; animation-direction:alternate; animation-play-state:running; /* Safari and Chrome: */ -webkit-animation-name:myfirst; -webkit-animation-duration:5s; -webkit-animation-timing-function:linear; -webkit-animation-delay:2s; -webkit-animation-iteration-count:infinite; -webkit-animation-direction:alternate; -webkit-animation-play-state:running; } @keyframes myfirst { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } @-webkit-keyframes myfirst /* Safari and Chrome */ { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } </style> </head> <body> <p><b>注意:</b> 该实例在 Internet Explorer 9 及更早 IE 版本是无效的。</p> <div></div> </body> </html>
与上面的动画相同,但是使用了简写的动画 animation 属性:(常用)
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> div { width:100px; height:100px; background:red; position:relative; animation:myfirst 5s linear 2s infinite alternate; /* Firefox: */ -moz-animation:myfirst 5s linear 2s infinite alternate; /* Safari and Chrome: */ -webkit-animation:myfirst 5s linear 2s infinite alternate; /* Opera: */ -o-animation:myfirst 5s linear 2s infinite alternate; } @keyframes myfirst { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } @-moz-keyframes myfirst /* Firefox */ { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } @-webkit-keyframes myfirst /* Safari and Chrome */ { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } @-o-keyframes myfirst /* Opera */ { 0% {background:red; left:0px; top:0px;} 25% {background:yellow; left:200px; top:0px;} 50% {background:blue; left:200px; top:200px;} 75% {background:green; left:0px; top:200px;} 100% {background:red; left:0px; top:0px;} } </style> </head> <body> <p><b>注意:</b> 该实例在 Internet Explorer 9 及更早 IE 版本是无效的。</p> <div></div> </body> </html>
完整的CSS3飘动例子:
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <style> #baseInfo { display:block; -webkit-animation: marquee1 15s linear infinite; animation: marquee1 15s linear infinite; } @keyframes marquee1 { 0% { transform: translateX(+0px); } 25% { transform: translateX(+60px); } 50% { transform: translateX(+120px); color:green; } 75% { transform: translateX(+60px); } 100% { transform: translateX(+0px); color:red; / / 每行高50 } } </style> <font size="5" style="margin-left: -95px" color="red" id="baseInfo">有远大抱负的人不可忽略眼前的工作!!!</font> </body> </html>
【当你用心写完每一篇博客之后,你会发现它比你用代码实现功能更有成就感!】