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iOS

Posted by Tom Coomer
Tom Coomer
1,331 Points

Local notifications in Swift

I am trying to create a local notification that repeats once a week. I have this code below but am show the following error message:

(The code is in App Delegate - didFinishLaunchingWithOptions)

        application.registerUserNotificationSettings(UIUserNotificationSettings (forTypes: UIUserNotificationType.Alert, categories: nil))

        var localNotification:UILocalNotification = UILocalNotification()
        localNotification.alertAction = "Testing"
        localNotification.alertBody = "Hello World!"
        localNotification.fireDate = NSDate(timeIntervalSinceNow: 5)
        UIApplication.sharedApplication().scheduleLocalNotification(localNotification)

Error message:

2014-09-17 10:48:10.821 Reaction Timer 4[5368:1507695] Attempting to schedule a local notification <UIConcreteLocalNotification: 0x178152bc0>{fire date = Wednesday, 17 September 2014 10:48:15 British Summer Time, time zone = (null), repeat interval = 0, repeat count = UILocalNotificationInfiniteRepeatCount, next fire date = Wednesday, 17 September 2014 10:48:15 British Summer Time, user info = (null)} with an alert but haven't received permission from the user to display alerts

2 Answers

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

You need to register your app for displaying local notifications in iOS8. Add this snippet to your application(_:didFinishLaunchingWithOptions:) method:

application.registerUserNotificationSettings(UIUserNotificationSettings(forTypes: UIUserNotificationType.Sound | UIUserNotificationType.Alert | UIUserNotificationType.Badge, categories: nil))

You can read the documentation on application(_:didRegisterUserNotificationSettings:) here.

Only after that's done it's possible to create a notification. I suggest you move the notification code to a viewDidLoad method of your main view controller, or anywhere where the notification will be created after the user has allowed notifications.

Tom Coomer
Tom Coomer
1,331 Points

Thank you. I am no longer shown the error message however the notification still does not display. Do you know why this could be?

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

Well, if you're inside the app when the notification is shown, if you don't have code to handle the notification, nothing will happen. Check the Notification Center of your device/simulator to see if the notification is shown there.

Tom Coomer
Tom Coomer
1,331 Points

Ah. Thank you! I have added this line:

localNotification.repeatInterval = NSCalendarUnit.CalendarUnitMinute

and I am now being shown a new notification every minute however I am being shown two each time. Do you know why this could be?

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

I'm not sure, to be honest. I tried to replicate the issue, but notifications are firing off as they're supposed to, one at a time, every minute.

Tom Coomer
Tom Coomer
1,331 Points

I created the notification then chnaged the action and body and it fires one with the new and one with the old.

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

Ah, in that case the old notification is still scheduled, alongside the new one. You have to cancel the old one.

For debugging purposes, you can do this:

println(UIApplication.sharedApplication().scheduledLocalNotifications)

to see all the local notifications that are scheduled.

Tom Coomer
Tom Coomer
1,331 Points

It still fires the old notification too. Do you now how to cancel the old ones?

Dino Paškvan
Dino Paškvan
Courses Plus Student 44,108 Points

You can iterate through UIApplication.sharedApplication().scheduledLocalNotifications and then use UIApplication.sharedApplication().cancelLocalNotification(notification) to cancel a particular notification.

Or you can cancel all prior scheduled notifications before attempting to create new ones with UIApplication.sharedApplication().cancelAllLocalNotifications().

Tom Coomer
Tom Coomer
1,331 Points

Great! Thanks for your help.

durul
durul
62,690 Points
durul
durul
62,690 Points

import UIKit

class TrackerReminderVC: UIViewController {

@IBOutlet weak var switchMorning: UISwitch!
@IBOutlet weak var switchAfternoon: UISwitch!
@IBOutlet weak var switchEvening: UISwitch!
@IBOutlet weak var switchBedtime: UISwitch!
@IBOutlet weak var xMorning: UILabel!
@IBOutlet weak var xAfternoon: UILabel!
@IBOutlet weak var xEvening: UILabel!
@IBOutlet weak var xBedtime: UILabel!

@IBOutlet weak var switchReminderMorning: UISwitch!
@IBOutlet weak var switchReminderAfternoon: UISwitch!
@IBOutlet weak var switchReminderEvening: UISwitch!
@IBOutlet weak var switchReminderBedtime: UISwitch!
@IBOutlet weak var xReminderMorning: UILabel!
@IBOutlet weak var xReminderAfternoon: UILabel!
@IBOutlet weak var xReminderEvening: UILabel!
@IBOutlet weak var xReminderBedtime: UILabel!

var storedDate = ""
var currentDate = ""

let defaults = NSUserDefaults.standardUserDefaults()

override func viewDidLoad() {
    super.viewDidLoad()

    if let daterecorded = defaults.stringForKey("storeddate") {
        storedDate = daterecorded
    }

    currentDate = getDate()

    if currentDate == storedDate {

        if let _ = defaults.stringForKey("takenmorning") {
            switchMorning.setOn(true, animated: true)
            xMorning.text = "✔︎"
            xMorning.textColor = UIColor.greenColor()
        }

        if let _ = defaults.stringForKey("takenafternoon") {
            switchAfternoon.setOn(true, animated: true)
            xAfternoon.text = "✔︎"
            xAfternoon.textColor = UIColor.greenColor()
        }

        if let _ = defaults.stringForKey("takenevening") {
            switchEvening.setOn(true, animated: true)
            xEvening.text = "✔︎"
            xEvening.textColor = UIColor.greenColor()
        }

        if let _ = defaults.stringForKey("takenbedtime") {
            switchBedtime.setOn(true, animated: true)
            xBedtime.text = "✔︎"
            xBedtime.textColor = UIColor.greenColor()
        }

    } else if currentDate != storedDate {

        defaults.removeObjectForKey("takenmorning")
        defaults.removeObjectForKey("takenafternoon")
        defaults.removeObjectForKey("takenevening")
        defaults.removeObjectForKey("takenbedtime")

        switchMorning.setOn(false, animated: true)
        switchAfternoon.setOn(false, animated: true)
        switchEvening.setOn(false, animated: true)
        switchBedtime.setOn(false, animated: true)

        xMorning.text = "✗"
        xMorning.textColor = UIColor.redColor()
        xAfternoon.text = "✗"
        xAfternoon.textColor = UIColor.redColor()
        xEvening.text = "✗"
        xEvening.textColor = UIColor.redColor()
        xBedtime.text = "✗"
        xBedtime.textColor = UIColor.redColor()
    }

    // for local notification buttons

    if let _ = defaults.stringForKey("remindermorning") {
        switchReminderMorning.setOn(true, animated: true)
        xReminderMorning.text = "✔︎"
        xReminderMorning.textColor = UIColor.greenColor()
    }

    if let _ = defaults.stringForKey("reminderafternoon") {
        switchReminderAfternoon.setOn(true, animated: true)
        xReminderAfternoon.text = "✔︎"
        xReminderAfternoon.textColor = UIColor.greenColor()
    }

    if let _ = defaults.stringForKey("reminderevening") {
        switchReminderEvening.setOn(true, animated: true)
        xReminderEvening.text = "✔︎"
        xReminderEvening.textColor = UIColor.greenColor()
    }

    if let _ = defaults.stringForKey("reminderbedtime") {
        switchReminderBedtime.setOn(true, animated: true)
        xReminderBedtime.text = "✔︎"
        xReminderBedtime.textColor = UIColor.greenColor()
    }

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

// Get date and time (in this case no time)
func getDate() -> String {
    let date = NSDateFormatter.localizedStringFromDate(NSDate(), dateStyle: .MediumStyle, timeStyle: .NoStyle)
    print(date)
    return date
}

@IBAction func morningSwitchTapped(sender: UISwitch) {

    storedDate = getDate()

    if switchMorning.on {
        defaults.setObject(storedDate, forKey: "storeddate")
        defaults.setObject(switchMorning.on, forKey: "takenmorning")
        switchMorning.setOn(true, animated: true)
        xMorning.text = "✔︎"
        xMorning.textColor = UIColor.greenColor()
    } else {
        if let _ = defaults.stringForKey("takenmorning") {
            xMorning.text = "✗"
            xMorning.textColor = UIColor.redColor()
            switchMorning.setOn(false, animated: true)
            defaults.removeObjectForKey("takenmorning")
        }
    }

}

@IBAction func afternoonSwitchTapped(sender: UISwitch) {

    storedDate = getDate()

    if switchAfternoon.on {
        defaults.setObject(storedDate, forKey: "storeddate")
        defaults.setObject(switchAfternoon.on, forKey: "takenafternoon")
        switchAfternoon.setOn(true, animated: true)
        xAfternoon.text = "✔︎"
        xAfternoon.textColor = UIColor.greenColor()
    } else {
        if let _ = defaults.stringForKey("takenafternoon") {
            xAfternoon.text = "✗"
            xAfternoon.textColor = UIColor.redColor()
            switchAfternoon.setOn(false, animated: true)
            defaults.removeObjectForKey("takenafternoon")
        }
    }

}

@IBAction func eveningSwitchTapped(sender: UISwitch) {

    storedDate = getDate()

    if switchEvening.on {
        defaults.setObject(storedDate, forKey: "storeddate")
        defaults.setObject(switchEvening.on, forKey: "takenevening")
        switchEvening.setOn(true, animated: true)
        xEvening.text = "✔︎"
        xEvening.textColor = UIColor.greenColor()
    } else {
        if let _ = defaults.stringForKey("takenevening") {
            xEvening.text = "✗"
            xEvening.textColor = UIColor.redColor()
            switchEvening.setOn(false, animated: true)
            defaults.removeObjectForKey("takenevening")
        }
    }

}

@IBAction func bedtimeSwitchTapped(sender: UISwitch) {

    storedDate = getDate()

    if switchBedtime.on {
        defaults.setObject(storedDate, forKey: "storeddate")
        defaults.setObject(switchBedtime.on, forKey: "takenbedtime")
        switchBedtime.setOn(true, animated: true)
        xBedtime.text = "✔︎"
        xBedtime.textColor = UIColor.greenColor()
    } else {
        if let _ = defaults.stringForKey("takenbedtime") {
            xBedtime.text = "✗"
            xBedtime.textColor = UIColor.redColor()
            switchBedtime.setOn(false, animated: true)
            defaults.removeObjectForKey("takenbedtime")
        }
    }

}


var morningNotification = UILocalNotification()

@IBAction func morningReminderTapped(sender: UISwitch) {

    if switchReminderMorning.on {

        defaults.setObject(switchReminderMorning.on, forKey: "remindermorning")

        let theDate = NSDate()
        let cal = NSCalendar.currentCalendar()
        cal.timeZone = NSCalendar.currentCalendar().timeZone
        let fireDate = cal.dateBySettingHour(9, minute: 0, second: 0, ofDate: theDate, options: NSCalendarOptions())

        morningNotification.alertBody = "Did you take your morning pills today?"
        morningNotification.repeatInterval = NSCalendarUnit.Day
        morningNotification.fireDate = fireDate
        morningNotification.soundName = UILocalNotificationDefaultSoundName
        UIApplication.sharedApplication().scheduleLocalNotification(morningNotification)

        xReminderMorning.text = "✔︎"
        xReminderMorning.textColor = UIColor.greenColor()
    } else {

        defaults.removeObjectForKey("remindermorning")

        UIApplication.sharedApplication().cancelLocalNotification(morningNotification)
        xReminderMorning.text = "✗"
        xReminderMorning.textColor = UIColor.redColor()

    }

}

var afternoonNotification = UILocalNotification()
@IBAction func afternoonReminderTapped(sender: UISwitch) {

    if switchReminderAfternoon.on {

        defaults.setObject(switchReminderAfternoon.on, forKey: "reminderafternoon")

        let theDate = NSDate()
        let cal = NSCalendar.currentCalendar()
        cal.timeZone = NSCalendar.currentCalendar().timeZone
        let fireDate = cal.dateBySettingHour(14, minute: 0, second: 0, ofDate: theDate, options: NSCalendarOptions())

        afternoonNotification.alertBody = "Did you take your afternoon pills today?"
        afternoonNotification.repeatInterval = NSCalendarUnit.Day
        afternoonNotification.fireDate = fireDate
        afternoonNotification.soundName = UILocalNotificationDefaultSoundName
        UIApplication.sharedApplication().scheduleLocalNotification(afternoonNotification)

        xReminderAfternoon.text = "✔︎"
        xReminderAfternoon.textColor = UIColor.greenColor()
    } else {

        defaults.removeObjectForKey("reminderafternoon")

        UIApplication.sharedApplication().cancelLocalNotification(afternoonNotification)
        xReminderAfternoon.text = "✗"
        xReminderAfternoon.textColor = UIColor.redColor()

    }

}

var eveningNotification = UILocalNotification()
@IBAction func eveningReminderTapped(sender: UISwitch) {

    if switchReminderEvening.on {

        defaults.setObject(switchReminderEvening.on, forKey: "reminderevening")

        let theDate = NSDate()
        let cal = NSCalendar.currentCalendar()
        cal.timeZone = NSCalendar.currentCalendar().timeZone
        let fireDate = cal.dateBySettingHour(19, minute: 0, second: 0, ofDate: theDate, options: NSCalendarOptions())

        eveningNotification.alertBody = "Did you take your evening pills tonight?"
        eveningNotification.repeatInterval = NSCalendarUnit.Day
        eveningNotification.fireDate = fireDate
        eveningNotification.soundName = UILocalNotificationDefaultSoundName
        UIApplication.sharedApplication().scheduleLocalNotification(eveningNotification)

        xReminderEvening.text = "✔︎"
        xReminderEvening.textColor = UIColor.greenColor()
    } else {

        defaults.removeObjectForKey("reminderevening")

        UIApplication.sharedApplication().cancelLocalNotification(eveningNotification)
        xReminderEvening.text = "✗"
        xReminderEvening.textColor = UIColor.redColor()

    }

}

var bedtimeNotification = UILocalNotification()
@IBAction func bedtimeReminderTapped(sender: UISwitch) {

    if switchReminderBedtime.on {

        defaults.setObject(switchReminderBedtime.on, forKey: "reminderbedtime")

        let theDate = NSDate()
        let cal = NSCalendar.currentCalendar()
        cal.timeZone = NSCalendar.currentCalendar().timeZone
        let fireDate = cal.dateBySettingHour(23, minute: 0, second: 0, ofDate: theDate, options: NSCalendarOptions())

        bedtimeNotification.alertBody = "Did you take your bedtime pills tonight?"
        bedtimeNotification.repeatInterval = NSCalendarUnit.Day
        bedtimeNotification.fireDate = fireDate
        bedtimeNotification.soundName = UILocalNotificationDefaultSoundName
        UIApplication.sharedApplication().scheduleLocalNotification(bedtimeNotification)

        xReminderBedtime.text = "✔︎"
        xReminderBedtime.textColor = UIColor.greenColor()
    } else {

        defaults.removeObjectForKey("reminderbedtime")

        UIApplication.sharedApplication().cancelLocalNotification(bedtimeNotification)
        xReminderBedtime.text = "✗"
        xReminderBedtime.textColor = UIColor.redColor()

    }

}

}