Objective-C: UILocalNotification - ios

Question

ViewController:
- (void)viewDidLoad
{
`[super viewDidLoad];`
dateFormatter.dateFormat = #"dd/MM";
timeFormatter.dateFormat = #"HH:mm";
NSString *dateString = [dateFormatter stringFromDate:dateTime];
NSString *timeString = [timeFormatter stringFromDate:dateTime];
if ([dateString isEqual:#"23/06"]) {
if ([timeString isEqual:#"23:30"]) {
UILocalNotification *localNotification = [[UILocalNotification alloc] init];
localNotification.fireDate = dateTime;
localNotification.alertBody = [NSString stringWithFormat:#"It's 11:30 PM 23th June!"];
localNotification.soundName = UILocalNotificationDefaultSoundName;
localNotification.applicationIconBadgeNumber = 1;
[[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
}
}
}
AppDelegate:
[[UIApplication sharedApplication] scheduledLocalNotifications];
if ([UIApplication instancesRespondToSelector:#selector(registerUserNotificationSettings:)]){
[application registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert|UIUserNotificationTypeBadge| UIUserNotificationTypeSound categories:nil]];
}
The notification isn't receiving when time equals string and date.
Please help!

Answer 1

The core issue with this (aside from using strings to compare dates) is that viewDidLoad gets called only once in this application. Because you are only scheduling the local notification when the current date is 11:30, it will never get called, since you also set the fireDate to the same exact time.
The thing is, local notifications get scheduled prior to the event. In fact, you should set dateTime to the desired schedule time and then set the local notification.
For example:
- (void)viewDidLoad {
[super viewDidLoad];
NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
[dateComponents setYear:2016];
[dateComponents setMonth:6];
[dateComponents setDay:23];
[dateComponents setHour:23];
[dateComponents setMinute:30];
dateTime = [[NSCalendar currentCalendar] dateFromComponents:dateComponents];
UILocalNotification *localNotification = [[UILocalNotification alloc] init];
localNotification.fireDate = dateTime;
localNotification.alertBody = [NSString stringWithFormat:#"It's 11:30 PM 23th June!"];
localNotification.soundName = UILocalNotificationDefaultSoundName;
localNotification.applicationIconBadgeNumber = 1;
[[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
}
Based on your uploaded code, it looks like you are going to be grabbing the date from the datePicker, so eventually, you will move the UILocalNotification portion to the button method and use [datePicker date] as the fireDate. Meaning, you can ignore the dateComponents part.