Ios 创建类别，以便一个对象可以成为另一个通常不会'；我不能

我有一个

UIWebView

，如果它能成为

NSURLConnection

的代理，我的生活会简单得多。我做了一个这样的分类

@interface UIWebView (NSURLConnectionDelegate) <NSURLConnectionDelegate> 

//these methods are used by the NSURLConnection, and are implemented in the .m
- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge;
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response;
- (BOOL)connectionShouldUseCredentialStorage:(NSURLConnection *)connection;

@end

但是当它是这样一个类别时，没有一个委托方法被调用

以前是否有人做过类似的事情，或者这不起作用，因为NSURLConnection认为

webview

实际上不是委托或其他什么

编辑以显示更多代码：

- (BOOL)webView:(UIWebView *)webview shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{

NSLog(@"shouldStartLoadWithRequest %@ %d", request.URL.absoluteURL.description, navigationType);
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];

if (!authed) {
    authed = NO; //gets set to yes when delegate methods work (also are some print outs in the delegate methods which are not printing at all)

    urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:webview];
    return NO;
}

return YES;
}

---

您确定执行该语句时

webview

是非空的（并且是正确的对象）？是的，非常确定，因为该连接位于

-（BOOL）webview:（UIWebView*）webview shouldStartLoadWithRequest:（NSURLRequest*）请求导航类型：（UIWebViewNavigationType）navigationType

我很确定我已经使用了类别来实现这样的委托，所以它确实有效。我会尝试再处理一些，可能犯了一个愚蠢的错误，你在哪里保留了对连接的引用以确保它不会被释放？看起来您并没有将其分配给任何对象，所以ARC可能是在调用堆栈中的某个位置取消分配它。

- (BOOL)webView:(UIWebView *)webview shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{

NSLog(@"shouldStartLoadWithRequest %@ %d", request.URL.absoluteURL.description, navigationType);
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];

if (!authed) {
    authed = NO; //gets set to yes when delegate methods work (also are some print outs in the delegate methods which are not printing at all)

    urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:webview];
    return NO;
}

return YES;
}