What does IBOutlet mean in Swift?

The type qualifier IBOutlet is a tag applied to an property declaration so that the Interface Builder application can recognize the property as an outlet and synchronize the display and connection of it with Xcode.

What is the use of IBOutlet?

IBOutlet is used when you want to do something with a View you created in Interface Builder. For example, you put a button in Interface Builder and you want to change it’s caption/label from your code, attach IBOutlet (with a name such as button1) to that button. Then from your code, you can call [button1 dosomething].

What does IBAction mean in Swift?

“Interface Builder”. Before Xcode 4, the interface files (XIBs and NIBs) were edited in a separate program called Interface Builder, hence the prefix. IBAction is defined to void , and IBOutlet to nothing. They are just clues to Interface Builder when parsing files to make them available for connections.

Why is IBOutlet weak?

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 IBOutlet and IBAction?

@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.

How does IBAction connect to storyboard?

To connect a button to an action, hold down control while clicking and dragging from the button to the action you want to attach it to.

What is Sender in IBAction?

The sender variable is normally the object that sent the action message (this isn’t exactly guaranteed — for example, you can send an action message yourself and pass anything you want — but that’s how it’s supposed to work). You can’t just write sender.

Why is IBOutlet weak in Swift?

What is the difference between ibaction and iboutletcollection?

Unlike IBAction or IBOutlet, IBOutletCollection takes a class name as an argument, which is, incidentally, as close to Apple-sanctioned generics as one gets in Objective-C. As a top-level object, an IBOutletCollection @property should be declared strong, with an NSArray * type:

What is an IBOutlet and how do I use it?

However, an IBOutlet can also be used to expose a top-level property, like another controller or a property that could then be accessed by a referencing view controller. As with anything in modern Objective-C, properties are preferred to direct ivar access. The same is true of IBOutlet s:

What is the role of ibibaction and IBOutlet?

IBAction, IBOutlet, and IBOutletCollection play important roles in development, on both the compiler level and human level. As Objective-C continues to rapidly evolve as a platform, it is likely that they may someday be as completely vestigial as the wings of flightless birds or eyes of cavefish.

How to create an action method in Objective-C using swift?

When you attach a button to the viewController, and create an action (IBAction) using ctrl-drag, you create a method (also called a function) that looks likes this in Swift (if it dose not have arguments): In objective-C the same thing will look like this: So that means that @IBAction func OK(sender: UIButton){} is an action method.