added uiControl publisher

Signed-off-by: Matt Bruce <matt.bruce@verizon.com>

VDS.xcodeproj/project.pbxproj

@@ -47,6 +47,7 @@
 		EAB1D2CD28ABE76100DAE764 /* Withable.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAB1D2CC28ABE76000DAE764 /* Withable.swift */; };
 		EAB1D2CF28ABEF2B00DAE764 /* Typography.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAB1D2CE28ABEF2B00DAE764 /* Typography.swift */; };
 		EAB1D2E628AE842000DAE764 /* Publisher+Bind.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAB1D2E328AE842000DAE764 /* Publisher+Bind.swift */; };
+		EAB1D2EA28AE84AA00DAE764 /* UIControlPublisher.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAB1D2E928AE84AA00DAE764 /* UIControlPublisher.swift */; };
 		EAF7F0952899861000B287F5 /* Checkbox.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAF7F0932899861000B287F5 /* Checkbox.swift */; };
 		EAF7F0962899861000B287F5 /* CheckboxModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAF7F0942899861000B287F5 /* CheckboxModel.swift */; };
 		EAF7F09A2899B17200B287F5 /* CATransaction.swift in Sources */ = {isa = PBXBuildFile; fileRef = EAF7F0992899B17200B287F5 /* CATransaction.swift */; };
@@ -128,6 +129,7 @@
 		EAB1D2CC28ABE76000DAE764 /* Withable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Withable.swift; sourceTree = "<group>"; };
 		EAB1D2CE28ABEF2B00DAE764 /* Typography.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Typography.swift; sourceTree = "<group>"; };
 		EAB1D2E328AE842000DAE764 /* Publisher+Bind.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "Publisher+Bind.swift"; sourceTree = "<group>"; };
+		EAB1D2E928AE84AA00DAE764 /* UIControlPublisher.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UIControlPublisher.swift; sourceTree = "<group>"; };
 		EAF7F0932899861000B287F5 /* Checkbox.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Checkbox.swift; sourceTree = "<group>"; };
 		EAF7F0942899861000B287F5 /* CheckboxModel.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CheckboxModel.swift; sourceTree = "<group>"; };
 		EAF7F0992899B17200B287F5 /* CATransaction.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CATransaction.swift; sourceTree = "<group>"; };
@@ -374,6 +376,7 @@
 			children = (
 				EAB1D2E328AE842000DAE764 /* Publisher+Bind.swift */,
 				EAB1D2C628A6E76300DAE764 /* ModelHandlerPublisher.swift */,
+				EAB1D2E928AE84AA00DAE764 /* UIControlPublisher.swift */,
 			);
 			path = Publishers;
 			sourceTree = "<group>";
@@ -560,6 +563,7 @@
 				EA33624728931B050071C351 /* Initable.swift in Sources */,
 				EAF7F0A4289B017C00B287F5 /* LabelAttributeModel.swift in Sources */,
 				EAF7F0B1289B177F00B287F5 /* LabelAttributeColor.swift in Sources */,
+				EAB1D2EA28AE84AA00DAE764 /* UIControlPublisher.swift in Sources */,
 				EAF7F13328A2A16500B287F5 /* LabelAttributeAttachment.swift in Sources */,
 				EAF7F0B9289C139800B287F5 /* ColorConfiguration.swift in Sources */,
 				EA3361BD288B2C760071C351 /* TypeAlias.swift in Sources */,

VDS/Publishers/UIControlPublisher.swift

@@ -0,0 +1,73 @@
+//
+//  UIControlPublisher.swift
+//  VDS
+//
+//  Created by Matt Bruce on 8/18/22.
+//
+
+import Foundation
+import UIKit
+import Combine
+
+/// A custom subscription to capture UIControl target events.
+final class UIControlSubscription<SubscriberType: Subscriber, Control: UIControl>: Subscription where SubscriberType.Input == Control {
+    private var subscriber: SubscriberType?
+    private let control: Control
+
+    init(subscriber: SubscriberType, control: Control, event: UIControl.Event) {
+        self.subscriber = subscriber
+        self.control = control
+        control.addTarget(self, action: #selector(eventHandler), for: event)
+    }
+
+    func request(_ demand: Subscribers.Demand) {
+        // We do nothing here as we only want to send events when they occur.
+        // See, for more info: https://developer.apple.com/documentation/combine/subscribers/demand
+    }
+
+    func cancel() {
+        subscriber = nil
+    }
+
+    @objc private func eventHandler() {
+        _ = subscriber?.receive(control)
+    }
+
+    deinit {
+        print("UIControlTarget deinit")
+    }
+}
+
+/// A custom `Publisher` to work with our custom `UIControlSubscription`.
+struct UIControlPublisher<Control: UIControl>: Publisher {
+
+    typealias Output = Control
+    typealias Failure = Never
+
+    let control: Control
+    let controlEvents: UIControl.Event
+
+    init(control: Control, events: UIControl.Event) {
+        self.control = control
+        self.controlEvents = events
+    }
+
+    /// This function is called to attach the specified `Subscriber` to this `Publisher` by `subscribe(_:)`
+    ///
+    /// - SeeAlso: `subscribe(_:)`
+    /// - Parameters:
+    ///     - subscriber: The subscriber to attach to this `Publisher`.
+    ///                   once attached it can begin to receive values.
+    func receive<S>(subscriber: S) where S : Subscriber, S.Failure == UIControlPublisher.Failure, S.Input == UIControlPublisher.Output {
+        subscriber.receive(subscription: UIControlSubscription(subscriber: subscriber, control: control, event: controlEvents))
+    }
+}
+
+/// Extending the `UIControl` types to be able to produce a `UIControl.Event` publisher.
+protocol CombineCompatible { }
+extension UIControl: CombineCompatible { }
+extension CombineCompatible where Self: UIControl {
+    func publisher(for events: UIControl.Event) -> UIControlPublisher<Self> {
+        return UIControlPublisher(control: self, events: events)
+    }
+}