//在程序的启动处，开启通知
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//.....
//开启网络状况的监听
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(reachabilityChanged:)
name: kReachabilityChangedNotification
object: nil];
hostReach = [[Reachability reachabilityWithHostName:@"www.google.com"] retain];//可以以多种形式初始化
[hostReach startNotifier]; //开始监听,会启动一个run loop
[self updateInterfaceWithReachability: hostReach];
//.....
}
// 连接改变
- (void) reachabilityChanged: (NSNotification* )note
{
Reachability* curReach = [note object];
NSParameterAssert([curReach isKindOfClass: [Reachability class]]);
[self updateInterfaceWithReachability: curReach];
}
//处理连接改变后的情况
- (void) updateInterfaceWithReachability: (Reachability*) curReach
{
//对连接改变做出响应的处理动作。
NetworkStatus status = [curReach currentReachabilityStatus];
if (status == NotReachable) { //没有连接到网络就弹出提实况
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"My App Name"
message:@"NotReachable"
delegate:nil
cancelButtonTitle:@"YES" otherButtonTitles:nil];
[alert show];
[alert release];
}
}