This post lists the many ways that I know to easily configure properties in Swift
Using a helper method
var label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
configureLabel()
}
func configureLabel() {
label = UILabel()
label.backgroundColor = UIColor.greenColor()
view.addSubview(label)
}
Using anonymous function
lazy var label: UILabel = { [weak self] in
let label = UILabel()
label.backgroundColor = UIColor.greenColor()
return label
}()
Ah, by the way, did you know that
- You shouldn't call access
labelin ViewControllerdeinit, because it islazyand we haveweak self -
lazyincreases your compile time
@noescape configure Block on init
I first saw it on https://github.com/AliSoftware/Dip/blob/develop/Sources/Dip.swift#L61
public init(@noescape configBlock: (DependencyContainer->()) = { _ in }) {
configBlock(self)
}
configure Block as extension
This https://github.com/devxoul/Then makes it easier to configure your property as an extension to NSObject
extension Then where Self: AnyObject {
public func then(@noescape block: Self -> Void) -> Self {
block(self)
return self
}
}
so we have
lazy var label: UILabel = UILabel().then { [weak self] in
$0.backgroundColor = UIColor.greenColor()
}
We have to declare label: UILabel to use [weak self]
init without extension
I try to avoid extension, after reading this http://nshipster.com/new-years-2016/
public func Init<Type>(value : Type, @noescape block: (object: Type) -> Void) -> Type
{
block(object: value)
return value
}
we can use it like
lazy var label: UILabel = Init(UILabel()) { [weak self] in
$0.backgroundColor = UIColor.greenColor()
}
We have to declare label: UILabel to use [weak self]
anonymous function again
This https://gist.github.com/erica/4fa60524d9b71bfa9819 makes configuration easier
lazy var label: UILabel = { [weak self] in
$0.backgroundColor = UIColor.greenColor()
return $0
}(UILabel())
Top comments (0)