Question

I get the bad access when followLink is called. This does not happen if I paste the openURL line into textContainsURL, so I’m assuming the object no longer exists once the method finishes? I’m new to this but I though ARC was supposed to handle this sort of thing for you?

@interface MyViewController : UIViewController
{   
NSURL *newsURL;
}

@end

following is in the implementation:

- (void)followLink
{ 
    [[UIApplication sharedApplication]openURL:newsURL];

}

- (BOOL)textContainsURL:(NSString*)text
{
    NSError *error = NULL;
    //scan text to see if there is a link and only set this up if there is
    NSDataDetector *detector = [NSDataDetector dataDetectorWithTypes:NSTextCheckingTypeLink error:&error];

    NSArray *matches = [detector matchesInString:text
                                     options:0
                                       range:NSMakeRange(0, [text length])];

    for (NSTextCheckingResult *match in matches) 
    {
        //NSRange matchRange = [match range];
        if ([match resultType] == NSTextCheckingTypeLink) 
        {
            newsURL = [[NSURL alloc] init];
            newsURL = [match URL];//what's the void state? retain it
            return YES;
        }
    }

    return NO;
}

Answer 1

You should copy the matched URL to your newsURL ivar or make your newsURL ivar a copy property and set the value through the accessor method. In your current code the URL is autoreleased.