Can I make #selector refer to a closure in Swift?

Question

I want to make a selector argument of my method refer to a closure property, both of them exist in the same scope. For example,

func backgroundC         


        

Answer 1

@werediver's answer is excellent. Here's an update that allows you to call it as a function.

import Foundation

public extension Selector {
  /// Wraps a closure in a `Selector`.
  /// - Note: Callable as a function.
  final class Perform: NSObject {
    public init(_ perform: @escaping () -> Void) {
      self.perform = perform
      super.init()
    }

    private let perform: () -> Void
  }
}

//MARK: public
public extension Selector.Perform {
  @objc func callAsFunction() { perform() }
  var selector: Selector { #selector(callAsFunction) }
}

You need to manage strong references to Selector.Performs. One way to do that is to subclass UIKit classes that were designed to work with target-action:

/// A `UITapGestureRecognizer` that wraps a closure.
public final class TapGestureRecognizer: UITapGestureRecognizer {
  public init(_ perform: @escaping () -> Void) {
    self.perform = .init(perform)
    super.init(target: self.perform, action: self.perform.selector)
  }

  public let perform: Selector.Perform
}

let tapRecognizer = TapGestureRecognizer { print("