自从更新到iOS 11.3之后，HTML输入字段不再可以使用JavaScript .focus（）进行聚焦，除非函数调用紧随触摸交互之后（过去可以随时使用.focus（））。有已知的解决方法吗？
在blur()之前呼叫focus() .....
似乎它们已被推送到仓库的一些更新：
https://github.com/ionic-team/cordova-plugin-wkwebview-engine/pull/171#issuecomment-377824347
因此请确保您删除cordova ios平台，添加最新版本的wkwebview：cordova-plugin-ionic-webview 1.1.19，然后添加npm install并添加平台ios。我刚刚测试了它的魅力。
将click函数添加到元素以调用焦点函数的效果很好。还是更好的解决方案？
<html>
<head>
<meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta charset="UTF-8">
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black">
<meta name="format-detection" content="telephone=no, email=no">
</head>
<body>
<input id="test" type="text" placeholder="test" />
<input id="test2" type="text" placeholder="test" />
<script src="https://cdn.bootcss.com/fastclick/1.0.6/fastclick.js"></script>
<script>
window.FastClick.attach(document.body);
document.getElementById('test').onclick = function(e) {
// works fine
e.target.focus();
};
document.getElementById('test2').onclick = function(e) {
// not working
setTimeout(function() {
e.target.focus();
}, 50)
};
</script>
</body>
</html>
这是我们当前在应用程序开发框架中使用的代码，以使input.focus（）正常工作。确认可正常使用并被Apple在App Store中接受：
Class class = NSClassFromString(@"WKContentView");
NSOperatingSystemVersion iOS_11_3_0 = (NSOperatingSystemVersion){11, 3, 0};
if ([[NSProcessInfo processInfo] isOperatingSystemAtLeastVersion: iOS_11_3_0]) {
SEL selector = sel_getUid("_startAssistingNode:userIsInteracting:blurPreviousNode:changingActivityState:userObject:");
Method method = class_getInstanceMethod(class, selector);
IMP original = method_getImplementation(method);
IMP override = imp_implementationWithBlock(^void(id me, void* arg0, BOOL arg1, BOOL arg2, BOOL arg3, id arg4) {
((void (*)(id, SEL, void*, BOOL, BOOL, BOOL, id))original)(me, selector, arg0, TRUE, arg2, arg3, arg4);
});
method_setImplementation(method, override);
} else {
SEL selector = sel_getUid("_startAssistingNode:userIsInteracting:blurPreviousNode:userObject:");
Method method = class_getInstanceMethod(class, selector);
IMP original = method_getImplementation(method);
IMP override = imp_implementationWithBlock(^void(id me, void* arg0, BOOL arg1, BOOL arg2, id arg3) {
((void (*)(id, SEL, void*, BOOL, BOOL, id))original)(me, selector, arg0, TRUE, arg2, arg3);
});
method_setImplementation(method, override);
}