UIWebView 中的 Javascript 回调到 C/Objective-C
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原文地址: http://stackoverflow.com/questions/2873899/
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Javascript in UIWebView callback to C/Objective-C
提问by LK.
Is there a way to get a callback to objective-c when a certain event has been detected in a UIWebView? Can Javascript send a callback to Objective-C?
当在 UIWebView 中检测到某个事件时，有没有办法回调到objective-c？Javascript 可以向 Objective-C 发送回调吗？
采纳答案by bpapa
Update - don't use UIWebView anymore. Use WKWebView, or better yet (if it fits your needs and you're building for iOS 9), a Safari View Controller.
更新 - 不再使用 UIWebView。使用 WKWebView，或者更好的（如果它满足您的需求并且您正在为 iOS 9 构建），一个 Safari 视图控制器。
But if you must use UIWebView, in your UIWebView delegate, provide an implementation for webView:shouldStartLoadWithRequest:navigationType:
但是如果你必须使用 UIWebView，在你的 UIWebView 委托中，提供webView:shouldStartLoadWithRequest:navigationType 的实现：
In your HTML or Javascript files, add functions that send URLs to a custom scheme (for readability purposes, the custom scheme isn't required). All the URLs sent will be passed to your Objective-C method implementation, and then you can do what you'd like.
在您的 HTML 或 Javascript 文件中，添加将 URL 发送到自定义方案的函数（出于可读性目的，不需要自定义方案）。所有发送的 URL 都会传递给你的 Objective-C 方法实现，然后你就可以做你想做的了。
回答by geon
Just to illustrate the solution by "bpapa" with actual code:
只是为了用实际代码说明“bpapa”的解决方案：
WARNING: untested code
警告：未经测试的代码
Implement this method in the UIWebView's delegate...
在 UIWebView 的委托中实现这个方法...
-(BOOL) webView:(UIWebView *)inWeb shouldStartLoadWithRequest:(NSURLRequest *)inRequest navigationType:(UIWebViewNavigationType)inType {
if ( [[[inRequest URL] scheme] isEqualToString:@"callback"] ) {
// Do something interesting...
return NO;
}
return YES;
}
...then put a link in the webwieb like this:
...然后在 webwieb 中放置一个链接，如下所示：
<a href="callback:whatever">Click me</a>
And it should activate your callback-code. Obviously, you could trigger it with a javascript instead of a plain link.
它应该激活您的回调代码。显然，您可以使用 javascript 而不是普通链接来触发它。
