UIWebView: how to catch page load event on ajax sites?

Question

Objective-C

Good afternoon!
Please tell me how to catch the page loading event on ajax sites when the delegate methods:

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

- (void)webViewDidFinishLoad:(UIWebView *)webView
are not called. Checked on m.vk.com.
I need this to block and unblock the back/forward buttons while navigating through pages.
Google prompted to dig in the direction of NSURLProtocol, but so far it is difficult to determine the transition to all m.vk.com links

Answer 1

If the buttons are always active, is there a problem with navigation? Methods goBack goForward fulfill?
In any case, NSURLProtocol can help. Here's a no-frills example . On the didReceiveResponse event, you can check canGoBack and canGoForward Google a
little on the topic, the guys on stackoverflow.com still have problems with html5 cache on iOS 7.

Answer 2

Hmm ... and when loading this page into the browser using my protocol, in general, the brakes and freezes are considerable. It seems to do everything like here :

@implementation WebBrowserURLProtocol
{
    NSURLConnection *_connection;
}

#pragma mark - NSURLProtocol

+ (BOOL)canInitWithRequest:(NSURLRequest *)request
{
    if ([NSURLProtocol propertyForKey:@"urlConnectionSent" inRequest:request] != nil)
        return NO;
    
    return YES;
}

+ (NSURLRequest *)canonicalRequestForRequest:(NSURLRequest *)request
{
    return request;
}

- (void)startLoading
{
    NSMutableURLRequest *newRequest = [self.request mutableCopy];
    
    [NSURLProtocol setProperty:@YES forKey:@"urlConnectionSent" inRequest:newRequest];
    
    _connection = [NSURLConnection connectionWithRequest:newRequest delegate:self];
}

- (void)stopLoading
{
    [_connection cancel];
}

#pragma mark - NSURLConnectionDelegate

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    [self.client URLProtocol:self didLoadData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    [self.client URLProtocol:self didFailWithError:error];
    _connection = nil;
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    [self.client URLProtocol:self didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageAllowed];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    [self.client URLProtocolDidFinishLoading:self];
    _connection = nil;
    
    [WebBrowserURLProtocol postNotification];
}

#pragma mark - Notifications

+(void)postNotification
{
    dispatch_async(dispatch_get_main_queue(), ^{
        [[NSNotificationCenter defaultCenter] postNotificationName:@"kURLProtocolDidFinishLoading" object:nil];
    });
}

@end

As a result, I rewrote the class using only one method in it
+ (BOOL)canInitWithRequest:(NSURLRequest *)request
and the brakes were gone. For the task of updating the back/forward buttons, this is quite tolerable:

@implementation WebBrowserURLProtocol

+(void)postNotification
{
    dispatch_async(dispatch_get_main_queue(), ^{
        [[NSNotificationCenter defaultCenter] postNotificationName:@"kURLProtocolDidFinishLoading" object:nil];
    });
}

+ (BOOL)canInitWithRequest:(NSURLRequest *)request
{
    [WebBrowserURLProtocol postNotification];
    
    return NO;
}

+ (NSURLRequest *)canonicalRequestForRequest:(NSURLRequest *)request
{
    return request;
}

- (void)startLoading
{
}

- (void)stopLoading
{
}

@end

from what such troubles with this class....?