我已经添加了 "viewport" 的元标签 "width=device-width,initial-scale=1.0", 在iPad上，页面在横向模式下加载正常，然后很好地切换到纵向模式。但是，当我将其旋转回横向时，它会将页面缩放并且我必须通过捏合缩放将其缩放回1比例。
我可以通过添加 "maximum-scale=1.0, user-scalable=no" 来解决这个问题，但我想知道是否有一种方法可以在不剥夺用户缩放页面的能力的情况下解决这个问题。
如果你有任何建议，我很乐意听取，
谢谢！
------ 更新 ------
iOS7中不再存在这个问题。Github上Scott Jehl提供了更好的解决方案 scottjehl/iOS-Orientationchange-Fix，适用于iOS6。
------ 原始回答 ------
Jeremy Keith (@adactio)在他的博客《方向和缩放》中有一个很好的解决方案。
保持标记可扩展。
<meta name="viewport" content="width=device-width, initial-scale=1">
然后使用以下脚本在gesturestart事件之前禁用JavaScript可扩展性：
if (navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i)) {
var viewportmeta = document.querySelector('meta[name="viewport"]');
if (viewportmeta) {
viewportmeta.content = 'width=device-width, minimum-scale=1.0, maximum-scale=1.0, initial-scale=1.0';
document.body.addEventListener('gesturestart', function () {
viewportmeta.content = 'width=device-width, minimum-scale=0.25, maximum-scale=1.6';
}, false);
}
}
navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i)会返回true。 - HandiworkNYC.comScott Jehl 想出了一个极好的解决方案，利用加速度计来预测方向变化。这个方案非常敏感且不会干扰缩放手势。
https://github.com/scottjehl/iOS-Orientationchange-Fix
它是如何工作的：这个修复程序通过监听设备的加速度计来预测方向变化即将发生的时间。当它认为方向变化即将发生时，脚本会禁用用户缩放，允许方向变化正确地进行，同时缩放被禁用。一旦设备朝向接近竖直或其朝向已经改变，脚本会再次恢复缩放。这样，在页面使用中从未禁用用户缩放。
压缩源代码：
/*! A fix for the iOS orientationchange zoom bug. Script by @scottjehl, rebound by @wilto.MIT License.*/(function(m){if(!(/iPhone|iPad|iPod/.test(navigator.platform)&&navigator.userAgent.indexOf("AppleWebKit")>-1)){return}var l=m.document;if(!l.querySelector){return}var n=l.querySelector("meta[name=viewport]"),a=n&&n.getAttribute("content"),k=a+",maximum-scale=1",d=a+",maximum-scale=10",g=true,j,i,h,c;if(!n){return}function f(){n.setAttribute("content",d);g=true}function b(){n.setAttribute("content",k);g=false}function e(o){c=o.accelerationIncludingGravity;j=Math.abs(c.x);i=Math.abs(c.y);h=Math.abs(c.z);if(!m.orientation&&(j>7||((h>6&&i<8||h<8&&i>6)&&j>5))){if(g){b()}}else{if(!g){f()}}}m.addEventListener("orientationchange",f,false);m.addEventListener("devicemotion",e,false)})(this);
(/iPhone|iPad|iPod/.test(navigator.platform) 在 iOS/iPadOS 13（Mobile Safari 13）的桌面模式下已经失效，因为它现在被设置为 MacIntel 在 iOS/iPadOS 上（在 Beta 2 上测试过）。 - robocat希望这能帮到你们，...
<head>
<style type="text/css">
<!--
/*
I began with the goal to prevent font scaling in Landscape orientation.
To do this, see: https://dev59.com/KnE85IYBdhLWcg3wkkfK
Later, I just wanted to magnify font-size for the iPad, leaving
the iPhone rendering to the css code. So ...
(max-device-width:480px) = iphone.css
(min-device-width:481px) and
(max-device-width:1024px) and
(orientation:portrait) = ipad-portrait.css
(min-device-width:481px) and
(max-device-width:1024px) and
(orientation:landscape) = ipad-landscape.css
(min-device-width:1025px) = ipad-landscape.css
*/
@media only screen and (min-device-width: 481px)
{
html {
-webkit-text-size-adjust: 140%; /* none for no scaling */
}
}
-->
</style>
</head>
font-size更改。 - SexxLuthor/*! A fix for the iOS orientationchange zoom bug. Script by @scottjehl, rebound by @wilto.MIT / GPLv2 License.*/(function (a) { function m() { d.setAttribute("content", g), h = !0 } function n() { d.setAttribute("content", f), h = !1 } function o(b) { l = b.accelerationIncludingGravity, i = Math.abs(l.x), j = Math.abs(l.y), k = Math.abs(l.z), (!a.orientation || a.orientation === 180) && (i > 7 || (k > 6 && j < 8 || k < 8 && j > 6) && i > 5) ? h && n() : h || m() } var b = navigator.userAgent; if (!(/iPhone|iPad|iPod/.test(navigator.platform) && /OS [1-5]_[0-9_]* like Mac OS X/i.test(b) && b.indexOf("AppleWebKit") > -1)) return; var c = a.document; if (!c.querySelector) return; var d = c.querySelector("meta[name=viewport]"), e = d && d.getAttribute("content"), f = e + ",maximum-scale=1", g = e + ",maximum-scale=10", h = !0, i, j, k, l; if (!d) return; a.addEventListener("orientationchange", m, !1), a.addEventListener("devicemotion", o, !1) })(this);
/*! A fix for the iOS orientationchange zoom bug.
Script by @scottjehl, rebound by @wilto.
MIT / GPLv2 License.
*/
(function(w){
// This fix addresses an iOS bug, so return early if the UA claims it's something else.
var ua = navigator.userAgent;
if( !( /iPhone|iPad|iPod/.test( navigator.platform ) && /OS [1-5]_[0-9_]* like Mac OS X/i.test(ua) && ua.indexOf( "AppleWebKit" ) > -1 ) ){
return;
}
var doc = w.document;
if( !doc.querySelector ){ return; }
var meta = doc.querySelector( "meta[name=viewport]" ),
initialContent = meta && meta.getAttribute( "content" ),
disabledZoom = initialContent + ",maximum-scale=1",
enabledZoom = initialContent + ",maximum-scale=10",
enabled = true,
x, y, z, aig;
if( !meta ){ return; }
function restoreZoom(){
meta.setAttribute( "content", enabledZoom );
enabled = true;
}
function disableZoom(){
meta.setAttribute( "content", disabledZoom );
enabled = false;
}
function checkTilt( e ){
aig = e.accelerationIncludingGravity;
x = Math.abs( aig.x );
y = Math.abs( aig.y );
z = Math.abs( aig.z );
// If portrait orientation and in one of the danger zones
if( (!w.orientation || w.orientation === 180) && ( x > 7 || ( ( z > 6 && y < 8 || z < 8 && y > 6 ) && x > 5 ) ) ){
if( enabled ){
disableZoom();
}
}
else if( !enabled ){
restoreZoom();
}
}
w.addEventListener( "orientationchange", restoreZoom, false );
w.addEventListener( "devicemotion", checkTilt, false );
})( this );
这个可以用！
<script >
// BUG orientation portrait/lanscape IOS //
if (navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i)) {
var viewportmeta = document.querySelector('meta[name="viewport"]');
if (viewportmeta) {
viewportmeta.content = 'width=device-width, minimum-scale=1.0, maximum-scale=1.0, initial-scale=1.0';
document.addEventListener('orientationchange', function () {
viewportmeta.content = 'width=device-width, minimum-scale=0.25, maximum-scale=1';
}, false);
}
}
</script>
这似乎是 iOS 4 中的一个错误，可以通过以下 Javascript 代码片段进行修复，但这将禁用用户的捏合缩放功能:
https://gist.github.com/901295/229d163414e22ebb14a6a6ba0b9777118f02e52d
当你说它扩展页面时，是所有元素还是只有文本字体大小？... 为了修复字体大小，您可以使用：
html {
-webkit-text-size-adjust: 100%;
}
<meta name="viewport" content="width=device-width, initial-scale=1">
<script ="text/javascript">
if (navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i)) {
var viewportmeta = document.querySelector('meta[name="viewport"]');
if (viewportmeta) {
viewportmeta.content = 'width=device-width, minimum-scale=.25, maximum-scale=1.6, initial-scale=.8';
document.body.addEventListener('gesturestart', function () {
viewportmeta.content = 'width=device-width, minimum-scale=0.25, maximum-scale=1.6';
}, false);
}
}