Switch state saved if sms sent - ios

Question

I have been trying to connect a switch to an SMS text which worked out fine, i was even able to save the state the switch was left in.
However now i need to save the state only if the SMS is sent, and if the user doesn't send the message but a switch is already turned on it should then alert them with a AlertView.
So far i have been able to save the state the switch was left it and connect a label to signify if it is "ON" or "OFF" in the SMS.
- (void)viewDidLoad {
NSUserDefaults *standardDefaults = [NSUserDefaults standardUserDefaults];
self->switch1.on = ([[standardDefaults stringForKey:#"switchKey"]
isEqualToString:#"On"]) ? (YES) : (NO);
if(switch1.on){
label.text = #"ON";
NSUserDefaults *defults = [NSUserDefaults standardUserDefaults];
[defults setObject:label.text forKey:#"labelkey"];
[defults synchronize];
} else label.text = #"OFF"; {
NSUserDefaults *defults = [NSUserDefaults standardUserDefaults];
[defults setObject:label.text forKey:#"labelkey"];
[defults synchronize];
}
label.text = [[NSUserDefaults standardUserDefaults]objectForKey:#"labelkey"];
}
- (IBAction)switchChanged:(UISwitch *)sender {
NSUserDefaults *standardDefaults = [NSUserDefaults standardUserDefaults];
if (sender.on == 0) {
label.text = #"OFF";
[standardDefaults setObject:#"Off" forKey:#"switchKey"];
} else if (sender.on == 1) {
label.text = #"ON";
[standardDefaults setObject:#"On" forKey:#"switchKey"];
}
[standardDefaults synchronize];
}
This is how i send the SMS.
- (IBAction)sendRequest:(id)sender
{
MFMessageComposeViewController *messageVC = [[MFMessageComposeViewController alloc] init];
messageVC.body = [#[label.text] componentsJoinedByString:#""];
messageVC.recipients = #[_phoneNumber.text];
messageVC.messageComposeDelegate = self;
[self presentViewController:messageVC animated:NO completion:NULL];
}

Answer 1

By using MFMessageComposeViewControllerDelegate delegate, you can find Message is sent or cancelled by user.
- (void)messageComposeViewController:(MFMessageComposeViewController *)controller didFinishWithResult:(MessageComposeResult) result
{
switch (result) {
case MessageComposeResultCancelled:
//show alert here as per your requirement break;
case MessageComposeResultFailed:
{
UIAlertView *warningAlert = [[UIAlertView alloc] initWithTitle:#"Error" message:#"Failed to send SMS!" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[warningAlert show];
break;
}
case MessageComposeResultSent:
break;
default:
break;
}
[self dismissViewControllerAnimated:YES completion:nil];
}
Refer this link -> Send sms