AleartView---無網路提醒

這功能很重要

沒有apple會把你給退件！

1.先下載.h .m檔，這是ARC compatible版本
https://github.com/tonymillion/Reachability

2.使用no-wifi aleart教學
http://paulpeelen.com/2011/11/30/ios-4-ios-5-tutorial-uialertview-with-link-to-wifi-or-settings-app-using-reachability-and-xcode-4-2/

3.注意教學文是就算有3g沒wi-fi也提醒喔，所以改成

- (void)checkForHOSTConnection {

Reachability *hostReach = [Reachability reachabilityWithHostname:@"www.google.com"];
NSString *netStatus = [hostReach currentReachabilityString];
//NSLog(@"currentReachabilityString = %@", netStatus);

if ([netStatus isEqualToString:@"No Connection"])
{
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"已關閉\"行動數據\"", @"AlertView")message:NSLocalizedString(@"開啟行動數據或使用WI-FI來取用資料。", @"AlertView")delegate:self cancelButtonTitle:NSLocalizedString(@"好", @"AlertView")otherButtonTitles:NSLocalizedString(@"設定", @"AlertView"), nil];
[alertView show];
}
}

會比較適當