Unused variable - xcode6

Question

I have same warning in xcode (Unused variable 'conn').
- (void)application:(UIApplication *)app didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
NSString *token = [deviceToken description];
token = [token stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:#"<>"]];
token = [token stringByReplacingOccurrencesOfString:#" " withString:#""];
[[NSUserDefaults standardUserDefaults] setObject:token forKey:#"deviceToken"];
NSData *postData = [[NSString stringWithFormat:#"token=%#", deviceToken] dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%lu",(unsigned long)[postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
//Don't forget to change the API link to your own link
[request setURL:[NSURL URLWithString:[NSString stringWithFormat:
#"http://mydomaine.com/push/savetoken/?device_token=%#&device_type=ios&channels_id=1", token]]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setHTTPBody:postData];
NSURLConnection *conn = [[NSURLConnection alloc]initWithRequest:request delegate:self];
NSLog(#"My device token is: %#", deviceToken);
}
- (void)application:(UIApplication*)application didFailToRegisterForRemoteNotificationsWithError:(NSError*)error {
NSLog(#"Failed to get token, error: %#", error);
}
Thanks

Answer 1

Well the compiler is correct; you create an instance of NSURLConnection which will be immediately destroyed when it goes out of scope.
NSURLConnection *conn = [[NSURLConnection alloc]initWithRequest:request delegate:self];
I suspect you want to keep a reference to the connection using an instance variable or #property:
#interface AppDelegate ()
{
NSURLConnection *_conn;
}
#end
and use:
_conn = [[NSURLConnection alloc]initWithRequest:request delegate:self];