如何从iOS Reachability Class更改网络连接通知？

Question

嗨我想捕获每当用户在我的应用程序中获得网络连接时,我已经添加了苹果Reachability类,下面是我在appDelegate类didFinishLaunchingWithOptions方法中使用的片段,

Reachability* reachability = [Reachability reachabilityForInternetConnection];
        [reachability startNotifier];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];

和我的reachabilityChanged选择器方法如下

- (void)reachabilityChanged:(NSNotification*)notification
{
    Reachability* reachability = notification.object;
    if(reachability.currentReachabilityStatus == NotReachable)
        NSLog(@"Internet off");
    else
        NSLog(@"Internet on");
}

但在这里,当我关闭飞机模式并在手机中获得网络连接时,我没有收到任何通知.

我错过了什么吗？

Answer 1

我在appdelegate中使用变量将当前网络状态存储为bool

@property (nonatomic, assign) BOOL hasInet;

.M

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    [self setUpRechability];
}


-(void)setUpRechability
{
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handleNetworkChange:) name:kReachabilityChangedNotification object:nil];

    reachability = [Reachability reachabilityForInternetConnection];
    [reachability startNotifier];

    NetworkStatus remoteHostStatus = [reachability currentReachabilityStatus];

    if          (remoteHostStatus == NotReachable)      {NSLog(@"no");      self.hasInet-=NO;   }
    else if     (remoteHostStatus == ReachableViaWiFi)  {NSLog(@"wifi");    self.hasInet-=YES;  }
    else if     (remoteHostStatus == ReachableViaWWAN)  {NSLog(@"cell");    self.hasInet-=YES;  }

}

- (void) handleNetworkChange:(NSNotification *)notice
{
    NetworkStatus remoteHostStatus = [reachability currentReachabilityStatus];

    if          (remoteHostStatus == NotReachable)      {NSLog(@"no");      self.hasInet-=NO;   }
    else if     (remoteHostStatus == ReachableViaWiFi)  {NSLog(@"wifi");    self.hasInet-=YES;  }
    else if     (remoteHostStatus == ReachableViaWWAN)  {NSLog(@"cell");    self.hasInet-=YES;  }

//    if (self.hasInet) {
//        UIAlertView *alert=[[UIAlertView alloc]initWithTitle:@"Net avail" message:@"" delegate:self cancelButtonTitle:OK_EN otherButtonTitles:nil, nil];
//        [alert show];
//    }
}

Answer 2

也许你应该在startnotifier之前添加观察者

[[NSNotificationCenter defaultCenter] addObserver: self selector: @selector(handleNetworkChange:) name: kReachabilityChangedNotification object: nil];
reachability = [Reachability reachabilityForInternetConnection];
[reachability startNotifier];