Questions tagged [protocol-extension]
90 questions
0
votes
1 answer
method in protocol extension gets called instead of method implementation in View Controller
so I have a viewController which holds a custom view,
and that viewController class conforms to ViewProtocol
I expect when someAction method triggered in someCustomizedView
it will print " method in otherCustomizedClass called "
but it prints ("…
Ian
- 239
- 1
- 14
0
votes
2 answers
"self as?" within protocol extension
I was trying for casting "self" within protocol extension. It crashed with EXC_BAD_ACCESS error when running on real device but worked well on simulator. What should I do to make this work? Thanks
My whole code:
protocol SomeProtocol: class…
Cuong Nguyen
- 376
- 1
- 5
- 8
0
votes
2 answers
Is this a bug in Xcode or a practice should be avoid by programmer?
In the first place, I looked for a way to simplify coding by providing default argument values for protocol functions. I took the solution here and then found some fatal subsequence it may bring:
protocol Foo {
func foo(_ a: Int)
}
extension…
Nandin Borjigin
- 2,094
- 1
- 16
- 37
0
votes
1 answer
How to invoke protocol extension default implementation with type constraints
Consider the following example:
class ManObj {
func baseFunc() {
print("ManObj baseFunc")
}
}
class SubObj: ManObj {
}
protocol Model {
}
extension Model { // This is protocol extension
func someFunc() { // Protocol extension…
ewcy
- 323
- 2
- 9
0
votes
2 answers
Protocol-Oriented Programming Extension variable init twice
Here is the situation. I have a protocol, and extension of it.
protocol CustomViewAddable {
var aView: UIView { get }
var bView: UIView { get }
func setupCustomView()
}
extension CustomViewAddable where Self: UIViewController {
var…
stan liu
- 1,712
- 1
- 11
- 14
0
votes
1 answer
Segmentation fault 11 for function naming in protocol extension
The problem is really simple. This causes a segmentation fault:
extension Sequence {
func parallelForEach(_ f: @escaping (T) -> R, completion: @escaping ([R]) -> ()) where Iterator.Element == T {
}
}
Clearly I don't know how to…
Richard Birkett
- 771
- 9
- 20
0
votes
0 answers
Swift Protocol Extensions: Adding #selector for a UIViewController
I am trying to add a UITapGestureRecognizer to a UIViewController via a swift protocol extension. I run into a problem when I try intialize the tapGestureRecognizer with a #selector. I have setup the following in a playground
protocol Tapable {
…
Lneuner
- 1,090
- 1
- 9
- 19
0
votes
1 answer
Swift protocol extension static-methods dispatch with superclass and subclass
I'm having a similar but slightly different problem described in: Swift protocol extension method dispatch with superclass and subclass.
The problem is related to static methods on protocols.
I have the following code:
protocol Protocol: class {
…
duhanebel
- 845
- 4
- 17
0
votes
0 answers
Swift: extending sequences with a generic element
In Swift, one can extend a sequence that contains elements of a particular type, e.g.:
extension SequenceType where Generator.Element == Rect {
func intersection() -> Rect? { ... }
}
// when using
let intersection = [rect1, rect2,…
MrMobster
- 1,851
- 16
- 25
0
votes
1 answer
Adding protocol conformance to existing class then checking if implements?
I'm trying to group a couple of existing classes into a single custom protocol so I can treat them the same. For example, I'd like to group these two classes together under a single protocol like this:
protocol CLKComplicationTemplateRingable {
…
TruMan1
- 33,665
- 59
- 184
- 335
0
votes
1 answer
Swift 2 Protocol extensions usage
I'm trying to catch up with this protocol-oriented-programming coolness using Swift 2 but I'm currently quite lost.
I'm trying to apply the theory to practical use cases so let's start with the most obvious:
Let's say I have a UITextField and I want…
rmvz3
- 1,133
- 2
- 16
- 27
0
votes
0 answers
Protocol extensions - unable to find matching property
Using these protocol definitions:
protocol Presenter: AnyObject {
typealias InteractorType
var interactor: InteractorType { get }
}
protocol Activable: AnyObject {
var active: Bool { get set }
}
extension Activable where Self:…
Jakub Vano
- 3,833
- 15
- 29
0
votes
1 answer
Swift 2.0: Protocol Extension Class Method returning Self
In order to extend some functionalities of my NSManagedObject subclasses, I have defined a series of protocols:
protocol ManagedObjectFindable {
static func find(format:String, arguments: [AnyObject]?, inContext context:NSManagedObjectContext,…
ambientlight
- 7,212
- 3
- 49
- 61
0
votes
1 answer
Stubbing methods for unit testing in swift 2
I am finding it difficult to stub methods in structs in swift. I can do it currently using a way that I'll explain below, but it feels wrong to me and would like an opinion on it.
I do not use any third party libraries for stubbing, instead I prefer…
Kedar
- 1,298
- 10
- 20
-1
votes
1 answer
Swift Extension computed variable not read correctly until declared in protocol
I have a protocol extension which declares and assigns a static computed variable:
protocol DataType {
}
extension DataType {
static var mocks: [Self] { [] }
}
Then I have another protocol named Provider which has an associatedtype…
apunn
- 97
- 8