iphone - 在 Reachability (2.0.3ddg) 方面需要一些帮助

Question

当我的应用程序启动时，我会检查可访问性，因为我需要即时的互联网连接。不过，我的问题是似乎没有立即确认 NetworkStatus，这意味着在设置可达性之后，我立即检查是否有连接，但它返回没有连接，无论如何我实际上是在使用 WiFi/3G，还是已关闭 radio 。

我可以确认我确实获得了 Internet 连接，因为在 applicationDidFinishLaunching 之后立即有一个通知，然后记录“ReachableViaWiFi”..

我做错了什么？为什么不立即确认有效的互联网连接？

- (void)applicationDidFinishLaunching:(UIApplication *)application {    
    NetworkStatus netStatus = [hostReach currentReachabilityStatus];
    if (netStatus == NotReachable) {
        ErrorViewController *errorViewController = [[ErrorViewController alloc] initWithNibName:@"ErrorView" bundle:[NSBundle mainBundle]];
        [tabBarController.view removeFromSuperview];
        [window addSubview:[errorViewController view]];
        return;
    }
}

-(void)setupReachability {
    [[NSNotificationCenter defaultCenter] addObserver: self selector: @selector(reachabilityChanged:) name:kReachabilityChangedNotification object: nil];
    hostReach = [[Reachability reachabilityWithHostName:@"www.google.com"] retain];
    [hostReach startNotifier];
}

-(void)reachabilityChanged:(NSNotification *)notification {
    Reachability* curReach = [notification object];
    NSParameterAssert([curReach isKindOfClass: [Reachability class]]);
    NetworkStatus netStatus = [curReach currentReachabilityStatus];
    BOOL connectionRequired = [curReach connectionRequired];
    switch (netStatus)
    {
        case NotReachable:
        {
            [[NSUserDefaults standardUserDefaults] setInteger:kNOTREACHABLE forKey:kREACHABILITYSTATUS];
            NSLog(@"NotReachable");
            connectionRequired = NO;  
            break;
        }

        case ReachableViaWWAN:
        {
            [[NSUserDefaults standardUserDefaults] setInteger:kREACHABLEVIAWWAN forKey:kREACHABILITYSTATUS];
            NSLog(@"ReachableViaWWAN");
            break;
        }
        case ReachableViaWiFi:
        {
            [[NSUserDefaults standardUserDefaults] setInteger:kNOTREACHABLE forKey:kREACHABILITYSTATUS];
            NSLog(@"ReachableViaWiFi");
            break;
        }
    }
}

Answer 1

好的，所以在我自己尝试了一些事情之后，我实际上通过添加一行额外的代码让它工作:

-(void)setupReachability {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotificationV2 object:nil];
    hostReach = [[ReachabilityV2 reachabilityWithHostName:@"www.google.com"] retain];
    [hostReach connectionRequired]; // this line was added, and apparently forces a connection requirement..
    [hostReach startNotifier];
}