What is an outlet in Swift?
An outlet is a property that is annotated with the symbol IBOutlet and whose value you can set graphically in a nib file or a storyboard. You declare an outlet in the interface of a class, and you make a connection between the outlet and another object in the nib file or storyboard.
What is an action in Swift?
Action – means a selector method which will be called on button’s tap event.
What is outlet programming?
An outlet is a property of an object that references another object.
What is the difference between @IBOutlet and IBAction?
An IBOutlet lets you reference the view from your controller code. An IBAction lets the view call a method in your controller code when the user interacts with the view.
Why outlets are weak Swift?
Outlets that you create will therefore typically be weak by default, because: Outlets that you create to, for example, subviews of a view controller’s view or a window controller’s window, are arbitrary references between objects that do not imply ownership.
What is the primary purpose of an outlet in an iOS app?
Outlets are the way your iOS app code can access — either by sending messages or setting properties — the Interface Builder objects in your storyboard. You can do all this graphically in Interface Builder, and the required code is generated for you.
What is a target Swift?
A target specifies a product to build and contains the instructions for building the product from a set of files in a project or workspace. A target inherits the project build settings, but you can override any of the project settings by specifying different settings at the target level.
What is #selector in Swift?
In Objective-C, a selector is a type that refers to the name of an Objective-C method. In Swift, you create a selector for an Objective-C method by placing the name of the method within the #selector expression: #selector(MyViewController.
What is the difference between outlet and action?
Outlet is used when you want to change some property of control i.e. text color or text size of a label. While Action is used when you want to detect a trigger i.e. when button is pressed.
What is IBAction and IBOutlet in Swift?
@IBAction is similar to @IBOutlet , but goes the other way: @IBOutlet is a way of connecting code to storyboard layouts, and @IBAction is a way of making storyboard layouts trigger code. This method takes one parameter, called sender . It’s of type UIButton because we know that’s what will be calling the method.
What is the purpose of an IBAction?
IBAction and IBOutlets are used to hook up your interface made in Interface Builder with your controller. If you wouldn’t use Interface Builder and build your interface completely in code, you could make a program without using them.
What is ARC in Swift?
Swift uses Automatic Reference Counting (ARC) to track and manage your app’s memory usage. ARC automatically frees up the memory used by class instances when those instances are no longer needed.
What is the difference between the action and the outlet?
The action provides a method to be called by a control (usually also a child view on the xib) when activated by the user. In other words, the outlet gives the obj-c code access to an object in IB; while the action gives the xib control access to the obj-c code.
What is the difference between action and outlet in UIViewController?
In other words, the outlet gives the obj-c code access to an object in IB; while the action gives the xib control access to the obj-c code. Outlet and Action connections are direct ways that a UIViewController can communicate with its UView.
What is Swift language used for?
Swift is a powerful and intuitive programming language for macOS, iOS, watchOS and tvOS. Writing Swift code is interactive and fun, the syntax is concise yet expressive, and Swift includes modern features developers love. Swift code is safe by design, yet also produces software that runs lightning-fast.
What are actions and outlets in iOS?
Actions and outlets in iOS are referred to as ibActions and ibOutlets respectively, where ib stands for interface builder. These are related to the UI elements and we will explore them after knowing visually how to implement them. Actions and Outlets – Steps Involved Step 1 − Let’s use our First iPhone Application.