An object containing information broadcast to registered observers that bridges to Notification ; use NSNotification when you need reference semantics or other Foundation-specific behavior. iOS 2.0+ iPadOS 2.0+ macOS 10.0+ Mac Catalyst 13.0+ tvOS 9.0+ watchOS 2.0+

What is Nsnotification in Swift?

Unlike push or local notifications where you are notifying a user of any content you would like them to receive, NSNotificationCenter allows us to send and receive information between classes and/or structs based on an action that has occurred in our app.

What is addObserver in Swift?

addObserver(forName:object:queue:using:) Adds an entry to the notification center to receive notifications that passed to the provided block.

What is NotificationCenter default post?

default — This is the notification variable you can create it globally inside your class if you having more notifications. addObserver(self, — This is for the class where we are going to observer notification.

What is notification observer in Swift?

Save. Notification Center use for broadcasting singles or notifying the methods at the same time. It uses the Observer pattern to inform registered observers when a notification comes in, using a central dispatcher called NotificationCenter.

What is Nsnotification name?

A structure that defines the name of a notification. Availability.

How many types of notification are there in iOS?

three different types

Apple provides three different types of notifications in iOS: NSNotificationCenter, UILocalNotification, and Remote Notifications. In addition, there has been a Notification Center to manage notifications since iOS 5. The three notifications have three very different uses.

What is Nsobject in Swift?

This protocol is imported into Swift with the name NSObjectProtocol . An object that conforms to this protocol can be considered a first-class object. Such an object can be asked about its: Class, and the place of its class in the inheritance hierarchy. Conformance to protocols.

What is #selector in Swift?

In Swift, Objective-C selectors are represented by the Selector structure, and you create them using the #selector expression. In Swift, you create a selector for an Objective-C method by placing the name of the method within the #selector expression: #selector(MyViewController. tappedButton(_:)) .

How do I use addObserver?

First, register an observer for a notification with: addObserver(_:selector:name:object:) Then, post a notification with post(name:object:userInfo:) … … after which your selector is called. And don’t forget to remove the observer with removeObserver()

What is user default in Swift?

The user defaults is a . plist file in your app’s package. You use it to set and get simple pieces of data. It’s structure is similar to that of a dictionary and the user defaults are often regarded as a key-value store.

How do I push notifications in Swift?

Quote from the video:
Quote from video: Come in and the way that you're actually going to send the notification is by going to cloud messaging on the left here under the engage.

What is notification history?

If you have ever deleted a notification a moment before you realized you needed it, Android 11 has a handy feature. Its notification history lets you browse dismissed alerts from the previous 24 hours.

How can I see my deleted notification history?

How to see deleted notifications on Android smartphones

  1. Open Settings on your Android smartphone.
  2. If you are using stock Android 11, go to Apps & Notifications. …
  3. Tap on ‘Notifications’ or ‘Manage notifications’.
  4. Tap on Notification history.
  5. Toggle on the Notification history feature.

Can you view iPhone notification history?

Notification Center shows your notifications history, allowing you to scroll back and see what you’ve missed. There are two ways to see your alerts from the Notification Center: From the Lock Screen, swipe up from the middle of the screen. From any other screen, swipe down from the center of the top of your screen.

Can you view old notifications on iPhone?

From the lock screen, swipe up from the middle to see your notifications. If your iPhone is already unlocked, you can swipe down from the top to see your old notifications.

Where are iPhone notifications stored?

Find your notifications in Notification Center



To see your notifications in Notification Center, do any of the following: On the Lock Screen: Swipe up from the middle of the screen. On other screens: Swipe down from the top center. Then you can scroll up to see older notifications, if there are any.

How do I clear all app notifications on iPhone?

Clear All Notifications

  1. Swipe down from the top left of the screen to show the Notification Center.
  2. Long press (deeply press 3D-Touch devices) on the X until “Clear All Notifications” appears.
  3. Tap on Clear All Notifications.


Why are notifications not showing on my iPhone?

Restart Your Device



If everything seems right in the Settings > Notification menu then it’s possible a software problem may be to blame. Try restarting your iPhone to see if this solves the problem.

What are banners in notifications?

Banner alerts are the notifications that appear at the top of your screen while you’re using another app on your iPhone or iPad. You see them most often with instant messaging apps, but they can be used for any kind of notification.

What’s a push alert?

Push notifications are small, pop-up messages sent to a user’s device by a mobile app that appear even when the app isn’t open. These notifications are designed to grab attention and can convey reminders, updates, promotions, and more. Push notifications can consist of a title, a message, an image, and a URL.

Why am I not receiving any notifications?

Check That Do Not Disturb is not enabled. It may seem obvious, but forgetting Do Not Disturb is enabled is one of the most common causes for not receiving notifications. If this setting is on (enabled), turn it off, and they will start working again. Restart your phone.

Why is my iPhone not notifying me when I receive a text from one person iOS 14?

Restart your device. See if the problem persists when iMessage is turned off. If this does work for you, this may represent a useful workaround. Because most users will want iMessage enabled, try re-enabling it by going to Settings > Messages and toggling the iMessage switch to the On position.

Why are my iMessages green?

If your iPhone messages are green, it means that they’re being sent as SMS text messages rather than as iMessages, which appear in blue. iMessages only work between Apple users. You’ll always see green when writing to Android users, or when you’re not connected to the internet.

How do you mark a message unread on IOS 14?

To mark the message unread, hold the arrow at the right that would be to open the message and read it. Start to swipe the message to the left and you will see a gray, orange and red box appear. If you swipe too far, you erase the message and will need to retrieve it from the Trash folder.