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Day 73 - Project21 - Challenge - Triggering Local Reminder 24hrs later

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Hey everyone! I was trying to solve challenge 2 for project21, when came across this thread Day 73 - Project21 - Challenge - Triggering Local Reminder 24hrs later (the original thread is archived so I can't reply there) However with this solution, if I force quit the app(press shift+command+H twice then swipe up project 21), the notification will never pop up again.

I came up with this "hack" later, which I believe is working after the app is killed, but just wanna know if there are better ways to solve it:

  1. Add a remindLater action in registerCatgories() function, with an empty array of options, and add this action to the category

    let remindLater = UNNotificationAction(identifier: "remind later", title: "Remind me later", options: [])
    let category = UNNotificationCategory(identifier: "alarm", actions: [show, remindLater], intentIdentifiers: [])
  2. add a case for the actionIdentifier in didReceive delegate method:

    case "remind later":
                scheduleLocalNotification(postpone: true)

This changes the scheduleNotification() method's signature, so modify the method accordingly, in next step

  1. change scheduleNotification():
    @objc func scheduleLocalNotification(postpone: Bool = false) {
    // What's originally there
    let timeInterval: Double = 5
    let trigger: UNTimeIntervalNotificationTrigger
    if postpone {
            trigger = UNTimeIntervalNotificationTrigger(timeInterval: 3, repeats: false)
    } else {
            trigger = UNTimeIntervalNotificationTrigger(timeInterval: timeInterval, repeats: false)
    // What's originally goes after

By default, the postpone parameter is set to false, so the timeInterval we set inside the method is used. when postpone is set to true, we add a given number of seconds to that(for testing purpose I added 3 second instead of 86400) the notification will be shown after the given time interval(In my case it's 3 seconds after clicking the "Remind me later" button.


One thing I forgot to metion: In project I didn't import UserNotifications as Paul did, but the project still works without any problem, anyone care to share some light on the reason?


Good idea @ladiesman218 !. I almost quit while handling that challenge. As I was trying to pass data in scheduleLocalNotification() but somehow it did not work. And then looking at your code I tried another appoach. I set time interval as a global variable like this:

var timeInterval: Double = 5

then in scheduleLocalNoficiation() changed trigger as:

let trigger = UNTimeIntervalNotificationTrigger(timeInterval: timeInterval, repeats: false)

and what is left to do is: change in didRecieve case as:

case "remind":
        timeInterval = 86400

and voila it works :) and the code is shorter


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