updated source code

packages/webview_flutter/webview_flutter_wkwebview/darwin/Tests/ColorProxyAPITests.swift

@@ -0,0 +1,18 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import UIKit
+import XCTest
+
+@testable import webview_flutter_wkwebview
+
+class ColorProxyAPITests: XCTestCase {
+  func testPigeonDefaultConstructor() {
+    let registrar = TestProxyApiRegistrar()
+    let api = registrar.apiDelegate.pigeonApiUIColor(registrar)
+
+    let instance = try? api.pigeonDelegate.pigeonDefaultConstructor(pigeonApi: api, red: 1.0, green: 1.0, blue: 1.0, alpha: 1.0)
+    XCTAssertNotNil(instance)
+  }
+}

packages/webview_flutter/webview_flutter_wkwebview/darwin/Tests/UIViewProxyAPITests.swift

@@ -17,14 +17,12 @@ class UIViewProxyAPITests: XCTestCase {
       let api = registrar.apiDelegate.pigeonApiUIView(registrar)
 
       let instance = UIView(frame: .zero)
-      let value = 0xFFF4_4336
+      let red = 0.5
+      let green = 0.5
+      let blue = 0.5
+      let alpha = 0.5
       try? api.pigeonDelegate.setBackgroundColor(
-        pigeonApi: api, pigeonInstance: instance, value: Int64(value))
-
-      let red = CGFloat(Double((value >> 16 & 0xff)) / 255.0)
-      let green = CGFloat(Double(value >> 8 & 0xff) / 255.0)
-      let blue = CGFloat(Double(value & 0xff) / 255.0)
-      let alpha = CGFloat(Double(value >> 24 & 0xff) / 255.0)
+        pigeonApi: api, pigeonInstance: instance, value: UIColor(red: red, green: green, blue: blue, alpha: alpha))
 
       XCTAssertEqual(
         instance.backgroundColor, UIColor(red: red, green: green, blue: blue, alpha: alpha))

packages/webview_flutter/webview_flutter_wkwebview/darwin/webview_flutter_wkwebview/Sources/webview_flutter_wkwebview/ColorProxyAPIDelegate.swift

@@ -0,0 +1,16 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import Foundation
+import UIKit
+
+/// ProxyApi implementation for `UIColor`.
+///
+/// This class may handle instantiating native object instances that are attached to a Dart instance
+/// or handle method calls on the associated native class or an instance of that class.
+class ColorProxyAPIDelegate : PigeonApiDelegateUIColor {
+  func pigeonDefaultConstructor(pigeonApi: PigeonApiUIColor, red: Double, green: Double, blue: Double, alpha: Double) throws -> UIColor {
+    return UIColor(red: red, green: green, blue: blue, alpha: alpha)
+  }
+}

packages/webview_flutter/webview_flutter_wkwebview/darwin/webview_flutter_wkwebview/Sources/webview_flutter_wkwebview/ProxyAPIRegistrar.swift

@@ -301,4 +301,8 @@ class ProxyAPIDelegate: WebKitLibraryPigeonProxyApiDelegate {
     return PigeonApiSecCertificate(
       pigeonRegistrar: registrar, delegate: SecCertificateProxyAPIDelegate())
   }
+
+  func pigeonApiUIColor(_ registrar: WebKitLibraryPigeonProxyApiRegistrar) -> PigeonApiUIColor {
+    return PigeonApiUIColor(pigeonRegistrar: registrar, delegate: ColorProxyAPIDelegate())
+  }
 }

packages/webview_flutter/webview_flutter_wkwebview/darwin/webview_flutter_wkwebview/Sources/webview_flutter_wkwebview/UIViewProxyAPIDelegate.swift

@@ -12,19 +12,10 @@
 /// or handle method calls on the associated native class or an instance of that class.
 class UIViewProxyAPIDelegate: PigeonApiDelegateUIView {
   #if os(iOS)
-    func setBackgroundColor(pigeonApi: PigeonApiUIView, pigeonInstance: UIView, value: Int64?)
+    func setBackgroundColor(pigeonApi: PigeonApiUIView, pigeonInstance: UIView, value: UIColor?)
       throws
     {
-      if value == nil {
-        pigeonInstance.backgroundColor = nil
-      } else {
-        let red = CGFloat(Double((value! >> 16 & 0xff)) / 255.0)
-        let green = CGFloat(Double(value! >> 8 & 0xff) / 255.0)
-        let blue = CGFloat(Double(value! & 0xff) / 255.0)
-        let alpha = CGFloat(Double(value! >> 24 & 0xff) / 255.0)
-
-        pigeonInstance.backgroundColor = UIColor(red: red, green: green, blue: blue, alpha: alpha)
-      }
+      pigeonInstance.backgroundColor = value
     }
 
     func setOpaque(pigeonApi: PigeonApiUIView, pigeonInstance: UIView, opaque: Bool) throws {

packages/webview_flutter/webview_flutter_wkwebview/lib/src/common/platform_webview.dart

@@ -324,7 +324,7 @@ class PlatformWebView {
   }
 
   /// The view’s background color.
-  Future<void> setBackgroundColor(int? value) {
+  Future<void> setBackgroundColor(UIColor? value) {
     final WKWebView webView = nativeWebView;
     switch (webView) {
       case UIViewWKWebView():