Add Switch UIViewRepresentable (#107)

Author: Kyle-Ye

Sources/OpenSwiftUI/Integration/Representable/Platform/PlatformViewRepresentable.swift

@@ -57,3 +57,13 @@ struct PlatformViewRepresentableContext<RepresentableType: PlatformViewRepresent
     var values: PlatformViewRepresentableValues
     let coordinator: RepresentableType.Coordinator
 }
+
+
+// TODO
+class PlatformViewCoordinator: NSObject {
+//    var weakDispatchUpdate: (()->Void) -> Void
+    
+    override init() {
+        super.init()
+    }
+}

Sources/OpenSwiftUI/View/Toggle/Switch.swift

@@ -0,0 +1,86 @@
+//
+//  Switch.swift
+//  OpenSwiftUI
+//
+//  Audited for RELEASE_2021
+//  Status: Blocked by Color
+//  ID: 1246D37251EA3A918B392E2B95F8B7EF
+
+#if os(iOS)
+import UIKit
+
+// FIXME
+struct Color {}
+
+private struct Switch: UIViewRepresentable {
+    typealias UIViewType = UISwitch
+    typealias Coordinator = PlatformSwitchCoordinator
+    
+    @Binding var isOn: Bool
+    var tint: Color?
+    
+    func makeUIView(context: Context) -> UISwitch {
+        let view = UISwitch()
+        view.addTarget(
+            context.coordinator,
+            action: #selector(PlatformSwitchCoordinator.isOnChanged),
+            for: .valueChanged
+        )
+        return view
+    }
+    
+    func updateUIView(_ uiView: UISwitch, context: Context) {
+        let isOn = isOn
+        let animated: Bool
+        if let animation = context.transaction.animation, !context.transaction.disablesAnimations {
+            animated = true
+        } else {
+            animated = false
+        }
+        uiView.setOn(isOn, animated: animated)
+        uiView.preferredStyle = .sliding
+        
+        let color: UIColor?
+        if let tint {
+            // TODO: Resolve the color from the environment
+            color = nil
+        } else {
+            color = nil
+        }
+        let onTintColor = uiView.onTintColor
+        if let color {
+            if onTintColor == nil || color != onTintColor {
+                uiView.onTintColor = color
+            }
+        } else {
+            if onTintColor != nil {
+                uiView.onTintColor = nil
+            }
+        }
+        context.coordinator._isOn = _isOn
+    }
+    
+    func makeCoordinator() -> Coordinator {
+        PlatformSwitchCoordinator(isOn: _isOn)
+    }
+    
+}
+
+private class PlatformSwitchCoordinator: PlatformViewCoordinator {
+    var _isOn: Binding<Bool>
+    
+    init(isOn: Binding<Bool>) {
+        _isOn = isOn
+        super.init()
+    }
+
+    @objc
+    func isOnChanged(_ sender: UISwitch) {
+        Update.perform {
+            _isOn.wrappedValue = sender.isOn
+        }
+        sender.setOn(_isOn.wrappedValue, animated: true)
+    }
+}
+
+#endif