Question

I am currently a newbie to iOS development and trying to get the cache policy (NSURLRequestReturnCacheDataDontLoad) to pull from the cache to view a web page while being in offline on the iPhone (using airplane mode). I am currently using the Reachability API provided by Apple to figure out if the network/wifi connection is up and running or not. This works fine but when I go to airplane mode I am not getting a webpage to populate the UIWebView. Any suggestions would very helpful, I look around online but did not find much helpful links. Thanks.

The code is below:

*- (IBAction)refresh:(id)sender 
{
    NSURL *url = [NSURL URLWithString:_entry.articleUrl]; 
    NSURLRequest *webRequest = nil;

    NSString *articleUrl = [_entry.articleUrl substringFromIndex:7];

    NSArray *myArray = [articleUrl componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"/"]];

    NSString *hostUrl = [myArray objectAtIndex:0];

    NSLog(@"%@", hostUrl);
    Reachability *reachability = [Reachability reachabilityWithHostName:hostUrl];

    NetworkStatus netStatus = [reachability currentReachabilityStatus];

    [[NSURLCache sharedURLCache] setMemoryCapacity:1024*1024*10];

    // Verify current help file cache if we have network connection...
    if (netStatus == ReachableViaWWAN || netStatus == ReachableViaWiFi) 
    {
        webRequest = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30];   
    } 
    else 
    {
        // Network NOT reachable - show (local) cache if it exists
        webRequest = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReturnCacheDataDontLoad timeoutInterval:30];
    }

    [_webView loadRequest:webRequest];
}*

Answer 1

Unfortunately, UIWebView does not persist web page cache. I have never done this but using AFCache should work for cache persisting.

Also make sure you got the cached page in place. If the webpage is not cacheable (i.e. with Pragma: no-cache), UIWebView might still not cache it.