Question

How do I disable a button when there is no connection to a network / internet in iOS?

Answer 1

Check out the reachability code from Apple.

http://developer.apple.com/library/ios/#samplecode/Reachability/Introduction/Intro.html

and use it like this:

Reachability *reachabilityInstance = [[Reachability reachabilityForInternetConnection] retain];
[reachabilityInstance startNotifier];
NetworkStatus networkStatus = [reachabilityInstance currentReachabilityStatus];
BOOL connected = (networkStatus==ReachableViaWiFi || networkStatus==ReachableViaWWAN);