Extensions add new functionality to an existing class, structure, or enumeration type.
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Questions tagged [swift-extensions]
394 questions
0
votes
1 answer
fileprivate extension vs normal extension
I know the difference between private and fileprivate.
But what is the difference between
fileprivate extension UIStoryBoard { }
and
extension UIStoryBoard { }
Savan Kavaiya
- 33
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0
votes
2 answers
Is there a way to allow a Swift protocol extension to access something in a class that implements said protocol, but which nothing else can access?
Long-winded question I know. An example is probably simpler:
var thing = ThingDoer()
thing.doSomething()
class ThingDoer: DoThings {
private func sortOfPrivateDoSomething () {}
}
extension DoThings {
func doSomething () {
…
Joseph Beuys' Mum
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0
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2 answers
How to Extend URLRequest
The result of trying to write maintainable, clean code:
func fetchNumbersFromServer(completion: @escaping (NumbersResult) -> Void) {
let urlString = "https://some-site.com/some-file"
var request = URLRequest(url: URL.init(string:…
David
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0
votes
2 answers
Swift protocol default implementation for optional readonly variables
I have the following piece of code, the protocol MyDisplayable has three optional Strings, and I have a default implementation of the protocol via extension. My question is, since I'm sure the extension returns the three strings, is there a way I…
Heuristic
- 5,087
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0
votes
2 answers
How can I override this class function?
I have an extension class, where I'm extending UIButton like below, it's working fine.
extension UIButton {
class func backButtonTarget(_ target: Any, action: Selector) -> UIBarButtonItem {
let backButton = UIButton(frame:…
Abhishek Mitra
- 3,335
- 4
- 25
- 46
0
votes
1 answer
Extension for Resizing an image within a For Loop
I have written an extension to resize a given image:
extension NSImage {
func resizeImage(width: CGFloat, _ height: CGFloat) -> NSImage {
let img = NSImage(size: CGSize(width:width, height:height))
img.lockFocus()
let…
techno
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0 answers
Why can't I call function that was defaulted through protocol extension?
I have extended the following protocol with a default parameter.
protocol XDelegate {
func close(response: Bool, status: Status)
}
extension XDelegate{
func close(response: Bool, status: Status = .UNDEFINED){}
}
whenever I call…
mfaani
- 33,269
- 19
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0
votes
1 answer
UIView extension with optional properties
Here's my code right now:
@objc protocol BaseView {
@objc optional var header: UILabel { get set }
@objc optional var footer: UILabel { get set }
}
class ViewWithHeader: UIView, BaseView {
@IBOutlet var header: UILabel!
}
class…
Rawr
- 2,206
- 3
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0
votes
0 answers
Use original class variable in an Extension that conforms to a Protocol
I have a situation where I want to be able to use an existing field from a class to satisfy an extension to the class that specifies a protocol. Something like this:
class SomeThing {
var foo: String
}
protocol MyProtocol {
var foo: String…
Kevin
- 1,132
- 2
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- 24
0
votes
2 answers
Storing values in array vs creating an extension function in Swift
I was storing couple of UIColors inside an array and changed my code to get them as a return value of a function as an UIColor extension.
Array version:
var colors : [UIColor] = [UIColor(red:0.35, green:0.40, blue:0.45, alpha:1.00),…
mikro098
- 2,173
- 2
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- 48
0
votes
1 answer
UIButton Extension For UIBarButtonItem
I'm writing an extension by taking a swift file and did codes in following way:
import Foundation
import UIKit
extension UIButton{
func backButtonTarget(_ target: Any, action: Selector) -> UIBarButtonItem {
let backButton =…
Abhishek Mitra
- 3,335
- 4
- 25
- 46
0
votes
1 answer
Extending NSDecimalNumber to conform to ExpressibleByStringLiteral crashes LLDB RPC server
A playground contains only an extension of NSDecimalNumber that conforms it to ExpressibleByStringLiteral and a variable x that attempts to utilize that extension, and the LLDB RPC server crashes:
import Cocoa
extension NSDecimalNumber:…
Ky -
- 30,724
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0
votes
1 answer
Swift: Extend Array with generics method with namespace
I'm writing some extension methods for swift Array type.
The environment is Xcode8.3(8E162) and Swift3.1
I want to make the final code look like [1, 2, 3].cc.find { $0 < 2 } Here cc is like rx in RxSwift and snp in SnapKit.
To achieve that, I…
Cokile Ceoi
- 1,326
- 2
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- 26
0
votes
0 answers
Associated type in protocol extension
I want to create a protocol and extension which I will use in three different view controllers for API loading.
protocol WebAPILoader {
// URL of remote resource
var url: URL? { get set }
// Array supposed to store loaded data.
…
cap-slow
- 71
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0
votes
0 answers
Do Swift extensions take priority over subclasses?
I'm thinking of defining:
extension UIViewController {
override var prefersStatusBarHidden: Bool {
return true
}
}
Does this also work for subclasses, like:
class UINavigationController: UIViewController {
override var…
Kartick Vaddadi
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