Schedule Local Notifications at Specific times in the day

问题

I want to setup a daily notification system for my app. It should notify the user twice a day, once at 8:00 AM (Hey there, your set of morning doses is ready. Wanna check it out?) and once at 7:00 PM (Ssup! Your evening Dose is waiting inside). I know that by doing this i'll run out of notifications in a month since there's a 64 notifications cap (for local notifications) but by then, the app will be live and i'll be done setting up remote notifications update.

I've looked at this question: How to schedule a same local notification in swift and the .Day is all good. I just need to know how to do it twice a day at those specified times;. Thanks in advance!

EDIT: how to set the specific time on the notification is part of the problem. The NSDate API is giving me funny time intervals (sinceNow/Since1973). I just want to set it to fire at 7 PM. :-/ Can't quite seem to do it with these NSDate apis unless I'm missing something.

回答1:

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.
    let settings = UIUserNotificationSettings(forTypes: .Badge, categories: nil)
    UIApplication.sharedApplication().registerUserNotificationSettings(settings)

    let localNotification1 = UILocalNotification()
    localNotification1.alertBody = "Your alert message 111"
    localNotification1.timeZone = NSTimeZone.defaultTimeZone()
    localNotification1.fireDate = self.getEightAMDate()
    UIApplication.sharedApplication().scheduleLocalNotification(localNotification1)

    let localNotification2 = UILocalNotification()
    localNotification2.alertBody = "Your alert message22"
    localNotification2.timeZone = NSTimeZone.defaultTimeZone()
    localNotification2.fireDate = self.getSevenPMDate()
    UIApplication.sharedApplication().scheduleLocalNotification(localNotification2)
    return true
}

func getEightAMDate() -> NSDate? {
    let calendar: NSCalendar! = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)
    let now: NSDate! = NSDate()

    let date10h = calendar.dateBySettingHour(8, minute: 0, second: 0, ofDate: now, options: NSCalendarOptions.MatchFirst)!
    return date10h
}

func getSevenPMDate() -> NSDate? {
    let calendar: NSCalendar! = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)
    let now: NSDate! = NSDate()

    let date19h = calendar.dateBySettingHour(19, minute: 0, second: 0, ofDate: now, options: NSCalendarOptions.MatchFirst)!
    return date19h
}

回答2:

Update for Swift 4.2

import UserNotifications

In AppDelegate confirm to UNUserNotificationCenterDelegate and in didFinishLaunchingWithOptions

let center = UNUserNotificationCenter.current()
            center.delegate = self;
            center.requestAuthorization(options: [UNAuthorizationOptions.alert, .badge, .sound]) { (granted, error) in
                if !granted {
                    print("Permission Declined");
                }
            }

let content = UNMutableNotificationContent();
            content.title = "HI";
            content.body = "Your notification is here";
            content.sound = UNNotificationSound.default;

            let gregorian = Calendar(identifier: Calendar.Identifier.gregorian);
            let now = Date();
            var components = gregorian.dateComponents(in: .autoupdatingCurrent, from: now)

            let hours = [8,19];

            for hour in hours {
                components.timeZone = TimeZone.current
                components.hour = hour;
                components.minute = 00;
                components.second = 00;

                let date = gregorian.date(from: components);
                let formatter = DateFormatter();
                formatter.dateFormat = "MM-dd-yyyy HH:mm";

                guard let dates = date else {
                    return;
                }
                var fireDate: String? 
                fireDate = formatter.string(from: dates);
                print("\(fireDate ?? "")"); // Just to Check

                let dailyTrigger = Calendar.current.dateComponents([.hour, .minute, .second], from: dates);
                let trigger = UNCalendarNotificationTrigger.init(dateMatching: dailyTrigger, repeats: true);

                let identifier = "Local Notification"
                let request = UNNotificationRequest(identifier: identifier, content: content, trigger: trigger)

                center.add(request) { (error) in
                    if let error = error {
                        print("Error \(error.localizedDescription)")
                    }
                }
            }

来源：https://stackoverflow.com/questions/38135631/schedule-local-notifications-at-specific-times-in-the-day