Add KVO, Combine, and SwiftUI support (#42)

LaunchAtLogin.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		D92CFD2224C5D909005B91BE /* Toggle.swift in Sources */ = {isa = PBXBuildFile; fileRef = D92CFD2124C5D909005B91BE /* Toggle.swift */; };
 		E32E9B681EB87D7B000FEEE9 /* LaunchAtLogin.h in Headers */ = {isa = PBXBuildFile; fileRef = E32E9B661EB87D7B000FEEE9 /* LaunchAtLogin.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		E32E9B6F1EB87DC5000FEEE9 /* LaunchAtLogin.swift in Sources */ = {isa = PBXBuildFile; fileRef = E32E9B6E1EB87DC5000FEEE9 /* LaunchAtLogin.swift */; };
 		E32E9B771EB87EA3000FEEE9 /* main.swift in Sources */ = {isa = PBXBuildFile; fileRef = E32E9B761EB87EA3000FEEE9 /* main.swift */; };
@@ -26,6 +27,7 @@
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXFileReference section */
+		D92CFD2124C5D909005B91BE /* Toggle.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Toggle.swift; sourceTree = "<group>"; };
 		E32E9B631EB87D7B000FEEE9 /* LaunchAtLogin.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = LaunchAtLogin.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		E32E9B661EB87D7B000FEEE9 /* LaunchAtLogin.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = LaunchAtLogin.h; sourceTree = "<group>"; usesTabs = 1; };
 		E32E9B671EB87D7B000FEEE9 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -79,10 +81,11 @@
 		E32E9B651EB87D7B000FEEE9 /* LaunchAtLogin */ = {
 			isa = PBXGroup;
 			children = (
-				E32E9B6E1EB87DC5000FEEE9 /* LaunchAtLogin.swift */,
-				E32E9B661EB87D7B000FEEE9 /* LaunchAtLogin.h */,
 				E32E9B921EB889AE000FEEE9 /* copy-helper.sh */,
 				E32E9B671EB87D7B000FEEE9 /* Info.plist */,
+				E32E9B661EB87D7B000FEEE9 /* LaunchAtLogin.h */,
+				E32E9B6E1EB87DC5000FEEE9 /* LaunchAtLogin.swift */,
+				D92CFD2124C5D909005B91BE /* Toggle.swift */,
 			);
 			path = LaunchAtLogin;
 			sourceTree = "<group>";
@@ -220,6 +223,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				E32E9B6F1EB87DC5000FEEE9 /* LaunchAtLogin.swift in Sources */,
+				D92CFD2224C5D909005B91BE /* Toggle.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

LaunchAtLogin/LaunchAtLogin.swift

@@ -1,7 +1,18 @@
+import Combine
 import Foundation
 import ServiceManagement
 
-public struct LaunchAtLogin {
+public enum LaunchAtLogin {
+	public static let kvo = KVO()
+
+	@available(macOS 10.15, *)
+	public static let observable = Observable()
+
+	@available(macOS 10.15, *)
+	private static var _publisher = CurrentValueSubject<Bool, Never>(isEnabled)
+	@available(macOS 10.15, *)
+	public static var publisher = _publisher.eraseToAnyPublisher()
+
 	private static let id = "\(Bundle.main.bundleIdentifier!)-LaunchAtLoginHelper"
 
 	public static var isEnabled: Bool {
@@ -15,7 +26,38 @@ public struct LaunchAtLogin {
 			return job?["OnDemand"] as? Bool ?? false
 		}
 		set {
+			if #available(macOS 10.15, *) {
+				observable.objectWillChange.send()
+			}
+
+			kvo.willChangeValue(for: \.isEnabled)
 			SMLoginItemSetEnabled(id as CFString, newValue)
+			kvo.didChangeValue(for: \.isEnabled)
+
+			if #available(macOS 10.15, *) {
+				_publisher.send(newValue)
+			}
+		}
+	}
+}
+
+// MARK: - LaunchAtLoginObservable
+extension LaunchAtLogin {
+	@available(macOS 10.15, *)
+	public final class Observable: ObservableObject {
+		public var isEnabled: Bool {
+			get { LaunchAtLogin.isEnabled }
+			set { LaunchAtLogin.isEnabled = newValue }
+		}
+	}
+}
+
+// MARK: - LaunchAtLoginKVO
+extension LaunchAtLogin {
+	public final class KVO: NSObject {
+		@objc dynamic public var isEnabled: Bool {
+			get { LaunchAtLogin.isEnabled }
+			set { LaunchAtLogin.isEnabled = newValue }
 		}
 	}
 }

LaunchAtLogin/Toggle.swift

@@ -0,0 +1,90 @@
+//
+//  LaunchAtLogin+Toggle.swift
+//  LaunchAtLogin
+//
+//  Created by Sergey Kuryanov on 20.07.2020.
+//  Copyright © 2020 Sindre Sorhus. All rights reserved.
+//
+
+import SwiftUI
+
+@available(macOS 10.15, *)
+extension LaunchAtLogin {
+	/// A control that toggles launch at login between on and off states.
+	///
+	/// You create a toggle by providing a label. Set the label to a view
+	/// that visually describes the purpose of switching between
+	/// launch at login states. For example:
+	///
+	///     var body: some View {
+	///         LaunchAtLogin.Toggle {
+	///             Text("Launch at login")
+	///         }
+	///     }
+	///
+	/// For the common case of text-only labels, you can use the convenience
+	/// initializer that takes a title string (or localized string key) as its first
+	/// parameter, instead of a trailing closure:
+	///
+	///     var body: some View {
+	///         LaunchAtLogin.Toggle("Launch at login")
+	///     }
+	///
+	/// Default initializer will use "Launch at login" as a title.
+	///
+	///     var body: some View {
+	///         LaunchAtLogin.Toggle()
+	///     }
+	///
+	public struct Toggle<Label>: View where Label: View {
+		@ObservedObject private var launchAtLogin = LaunchAtLogin.observable
+
+		public let label: Label
+
+		/// Creates a launch at login toggle that displays a custom label.
+		///
+		/// - Parameters:
+		///   - label: A view that describes the purpose of the toggle.
+		public init(@ViewBuilder label: () -> Label) {
+			self.label = label()
+		}
+
+		public var body: some View {
+			SwiftUI.Toggle(isOn: $launchAtLogin.isEnabled) {
+				label
+			}
+		}
+	}
+}
+
+@available(macOS 10.15, *)
+extension LaunchAtLogin.Toggle where Label == Text {
+	/// Creates a launch at login toggle that generates its label from a localized string key.
+	///
+	/// This initializer creates a ``Text`` view on your behalf with provided `titleKey`
+	///
+	/// - Parameters:
+	///   - titleKey: The key for the toggle's localized title, that describes
+	///     the purpose of the toggle.
+	public init(_ titleKey: LocalizedStringKey) {
+		label = Text(titleKey)
+	}
+
+	/// Creates a launch at login toggle that generates its label from a string.
+	///
+	/// This initializer creates a ``Text`` view on your behalf with provided `title`.
+	///
+	/// - Parameters:
+	///   - title: A string that describes the purpose of the toggle.
+	public init<S>(_ title: S) where S: StringProtocol {
+		label = Text(title)
+	}
+
+	/// Creates a launch at login toggle with default title.
+	///
+	/// This initializer creates a ``Text`` view on your behalf with ``Launch at login``
+	/// default title.
+	public init() {
+		self.init("Launch at login")
+	}
+}

readme.md

@@ -28,7 +28,13 @@ Add a new ["Run Script Phase"](http://stackoverflow.com/a/39633955/64949) **belo
 "${PROJECT_DIR}/Carthage/Build/Mac/LaunchAtLogin.framework/Resources/copy-helper.sh"
 ```
 
-Use it in your app:
+### Use it in your app:
+
+No need to store any state to UserDefaults.
+
+*Note that the [Mac App Store guidelines](https://developer.apple.com/app-store/review/guidelines/) requires “launch at login” functionality to be enabled in response to a user action. This is usually solved by making it a preference that is disabled by default. Many apps also let the user activate it in a welcome screen.*
+
+#### As static property:
 
 ```swift
 import LaunchAtLogin
@@ -42,9 +48,91 @@ print(LaunchAtLogin.isEnabled)
 //=> true
 ```
 
-No need to store any state to UserDefaults.
+#### SwiftUI:
 
-*Note that the [Mac App Store guidelines](https://developer.apple.com/app-store/review/guidelines/) requires “launch at login” functionality to be enabled in response to a user action. This is usually solved by making it a preference that is disabled by default. Many apps also let the user activate it in a welcome screen.*
+You can use `LaunchAtLogin.Toggle` view: a control that toggles launch at login between on and off states.
+
+You create a toggle by providing a label. Set the label to a view that visually describes the purpose of switching between launch at login states. For example:
+
+```swift
+struct ContentView: View {
+	var body: some View {
+		LaunchAtLogin.Toggle {
+			Text("Launch at login")
+		}
+	}
+}
+```
+
+For the common case of text-only labels, you can use the convenience initializer that takes a title string (or localized string key) as its first parameter, instead of a trailing closure:
+
+```swift
+struct ContentView: View {
+	var body: some View {
+		LaunchAtLogin.Toggle("Launch at login")
+	}
+}
+```
+Default initializer will use "Launch at login" as a title.
+
+```swift
+struct ContentView: View {
+	var body: some View {
+		LaunchAtLogin.Toggle()
+	}
+}
+```
+
+As alternative you can use `LaunchAtLogin.observable` as binding with `@ObservedObject`:
+
+```swift
+import SwiftUI
+import LaunchAtLogin
+
+struct ContentView: View {
+	@ObservedObject private var launchAtLogin = LaunchAtLogin.observable
+
+	var body: some View {
+		Toggle(isOn: $launchAtLogin.isEnabled) {
+			Text("Launch at login")
+		}
+	}
+}
+```
+#### Combine:
+
+Just subscribe to `LaunchAtLogin.publisher`:
+
+```swift
+import Combine
+import LaunchAtLogin
+
+final class ViewModel {
+	private var isLaunchAtLoginEnabled = LaunchAtLogin.isEnabled
+	private var cancellables = Set<AnyCancellable>()
+
+	func bind() {
+		LaunchAtLogin
+			.publisher
+			.assign(to: \.isLaunchAtLoginEnabled, on: self)
+			.store(in: &cancellables)
+	}
+}
+```
+
+#### Storyboards:
+
+Bind control to  `LaunchAtLogin.kvo` exposed property:
+
+```swift
+import Cocoa
+import LaunchAtLogin
+
+final class ViewController: NSViewController {
+	@objc dynamic var launchAtLogin = LaunchAtLogin.kvo
+}
+```
+![storyboard_binding](.github/storyboard_binding.png)
 
 ## How does it work?