[webview_flutter_wkwebview] Fixes exception from native WKWebViewConfiguration.defaultWebpagePreferences sometimes returning nil

packages/webview_flutter/webview_flutter_wkwebview/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 3.22.1
+
+* Fixes exception from native `WKWebViewConfiguration.defaultWebpagePreferences` sometimes returning
+  `nil`.
+
 ## 3.22.0
 
 * Adds support to respond to recoverable SSL certificate errors. See `WebKitNavigationDelegate.setOnSSlAuthError`.

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

@@ -135,4 +135,17 @@ class WebViewConfigurationProxyAPITests: XCTestCase {
 
     XCTAssertEqual(value, instance.defaultWebpagePreferences)
   }
+
+  @available(iOS 13.0, macOS 10.15, *)
+  @MainActor func testSetDefaultWebpagePreferences() {
+    let registrar = TestProxyApiRegistrar()
+    let api = registrar.apiDelegate.pigeonApiWKWebViewConfiguration(registrar)
+
+    let instance = WKWebViewConfiguration()
+    let preferences = WKWebpagePreferences()
+    try? api.pigeonDelegate.setDefaultWebpagePreferences(
+      pigeonApi: api, pigeonInstance: instance, preferences: preferences)
+
+    XCTAssertEqual(instance.defaultWebpagePreferences, preferences)
+  }
 }

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

@@ -8,6 +8,14 @@ import XCTest
 @testable import webview_flutter_wkwebview
 
 class WebpagePreferencesProxyAPITests: XCTestCase {
+  func testPigeonDefaultConstructor() {
+    let registrar = TestProxyApiRegistrar()
+    let api = registrar.apiDelegate.pigeonApiWKWebpagePreferences(registrar)
+
+    let instance = try? api.pigeonDelegate.pigeonDefaultConstructor(pigeonApi: api)
+    XCTAssertNotNil(instance)
+  }
+
   @available(iOS 14.0, macOS 11.0, *)
   @MainActor func testSetAllowsContentJavaScript() {
     let registrar = TestProxyApiRegistrar()

packages/webview_flutter/webview_flutter_wkwebview/darwin/webview_flutter_wkwebview/Sources/webview_flutter_wkwebview/WebKitLibrary.g.swift

@@ -3440,7 +3440,12 @@ protocol PigeonApiDelegateWKWebViewConfiguration {
   @available(iOS 13.0.0, macOS 10.15.0, *)
   func getDefaultWebpagePreferences(
     pigeonApi: PigeonApiWKWebViewConfiguration, pigeonInstance: WKWebViewConfiguration
-  ) throws -> WKWebpagePreferences
+  ) throws -> WKWebpagePreferences?
+  /// The default preferences to use when loading and rendering content.
+  @available(iOS 13.0.0, macOS 10.15.0, *)
+  func setDefaultWebpagePreferences(
+    pigeonApi: PigeonApiWKWebViewConfiguration, pigeonInstance: WKWebViewConfiguration,
+    preferences: WKWebpagePreferences) throws
 }
 
 protocol PigeonApiProtocolWKWebViewConfiguration {
@@ -3705,6 +3710,47 @@ final class PigeonApiWKWebViewConfiguration: PigeonApiProtocolWKWebViewConfigura
         getDefaultWebpagePreferencesChannel.setMessageHandler(nil)
       }
     }
+    if #available(iOS 13.0.0, macOS 10.15.0, *) {
+      let setDefaultWebpagePreferencesChannel = FlutterBasicMessageChannel(
+        name:
+          "dev.flutter.pigeon.webview_flutter_wkwebview.WKWebViewConfiguration.setDefaultWebpagePreferences",
+        binaryMessenger: binaryMessenger, codec: codec)
+      if let api = api {
+        setDefaultWebpagePreferencesChannel.setMessageHandler { message, reply in
+          let args = message as! [Any?]
+          let pigeonInstanceArg = args[0] as! WKWebViewConfiguration
+          let preferencesArg = args[1] as! WKWebpagePreferences
+          do {
+            try api.pigeonDelegate.setDefaultWebpagePreferences(
+              pigeonApi: api, pigeonInstance: pigeonInstanceArg, preferences: preferencesArg)
+            reply(wrapResult(nil))
+          } catch {
+            reply(wrapError(error))
+          }
+        }
+      } else {
+        setDefaultWebpagePreferencesChannel.setMessageHandler(nil)
+      }
+    } else {
+      let setDefaultWebpagePreferencesChannel = FlutterBasicMessageChannel(
+        name:
+          "dev.flutter.pigeon.webview_flutter_wkwebview.WKWebViewConfiguration.setDefaultWebpagePreferences",
+        binaryMessenger: binaryMessenger, codec: codec)
+      if api != nil {
+        setDefaultWebpagePreferencesChannel.setMessageHandler { message, reply in
+          reply(
+            wrapError(
+              FlutterError(
+                code: "PigeonUnsupportedOperationError",
+                message:
+                  "Call to setDefaultWebpagePreferences requires @available(iOS 13.0.0, macOS 10.15.0, *).",
+                details: nil
+              )))
+        }
+      } else {
+        setDefaultWebpagePreferencesChannel.setMessageHandler(nil)
+      }
+    }
   }
 
   ///Creates a Dart instance of WKWebViewConfiguration and attaches it to [pigeonInstance].
@@ -7150,6 +7196,10 @@ final class PigeonApiURL: PigeonApiProtocolURL {
   }
 }
 protocol PigeonApiDelegateWKWebpagePreferences {
+  /// Creates a `WKWebpagePreferences`.
+  @available(iOS 13.0.0, macOS 10.15.0, *)
+  func pigeonDefaultConstructor(pigeonApi: PigeonApiWKWebpagePreferences) throws
+    -> WKWebpagePreferences
   /// A Boolean value that indicates whether JavaScript from web content is
   /// allowed to run.
   @available(iOS 13.0.0, macOS 10.15.0, *)
@@ -7185,6 +7235,47 @@ final class PigeonApiWKWebpagePreferences: PigeonApiProtocolWKWebpagePreferences
         readerWriter: WebKitLibraryPigeonInternalProxyApiCodecReaderWriter(
           pigeonRegistrar: api!.pigeonRegistrar))
       : FlutterStandardMessageCodec.sharedInstance()
+    if #available(iOS 13.0.0, macOS 10.15.0, *) {
+      let pigeonDefaultConstructorChannel = FlutterBasicMessageChannel(
+        name:
+          "dev.flutter.pigeon.webview_flutter_wkwebview.WKWebpagePreferences.pigeon_defaultConstructor",
+        binaryMessenger: binaryMessenger, codec: codec)
+      if let api = api {
+        pigeonDefaultConstructorChannel.setMessageHandler { message, reply in
+          let args = message as! [Any?]
+          let pigeonIdentifierArg = args[0] as! Int64
+          do {
+            api.pigeonRegistrar.instanceManager.addDartCreatedInstance(
+              try api.pigeonDelegate.pigeonDefaultConstructor(pigeonApi: api),
+              withIdentifier: pigeonIdentifierArg)
+            reply(wrapResult(nil))
+          } catch {
+            reply(wrapError(error))
+          }
+        }
+      } else {
+        pigeonDefaultConstructorChannel.setMessageHandler(nil)
+      }
+    } else {
+      let pigeonDefaultConstructorChannel = FlutterBasicMessageChannel(
+        name:
+          "dev.flutter.pigeon.webview_flutter_wkwebview.WKWebpagePreferences.pigeon_defaultConstructor",
+        binaryMessenger: binaryMessenger, codec: codec)
+      if api != nil {
+        pigeonDefaultConstructorChannel.setMessageHandler { message, reply in
+          reply(
+            wrapError(
+              FlutterError(
+                code: "PigeonUnsupportedOperationError",
+                message:
+                  "Call to pigeonDefaultConstructor requires @available(iOS 13.0.0, macOS 10.15.0, *).",
+                details: nil
+              )))
+        }
+      } else {
+        pigeonDefaultConstructorChannel.setMessageHandler(nil)
+      }
+    }
     if #available(iOS 13.0.0, macOS 10.15.0, *) {
       let setAllowsContentJavaScriptChannel = FlutterBasicMessageChannel(
         name:

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

@@ -96,7 +96,15 @@ class WebViewConfigurationProxyAPIDelegate: PigeonApiDelegateWKWebViewConfigurat
   @available(iOS 13.0, macOS 10.15, *)
   func getDefaultWebpagePreferences(
     pigeonApi: PigeonApiWKWebViewConfiguration, pigeonInstance: WKWebViewConfiguration
-  ) throws -> WKWebpagePreferences {
+  ) throws -> WKWebpagePreferences? {
     return pigeonInstance.defaultWebpagePreferences
   }
+
+  @available(iOS 13.0, macOS 10.15, *)
+  func setDefaultWebpagePreferences(
+    pigeonApi: PigeonApiWKWebViewConfiguration, pigeonInstance: WKWebViewConfiguration,
+    preferences: WKWebpagePreferences
+  ) throws {
+    pigeonInstance.defaultWebpagePreferences = preferences
+  }
 }

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

@@ -9,6 +9,13 @@ import WebKit
 /// 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 WebpagePreferencesProxyAPIDelegate: PigeonApiDelegateWKWebpagePreferences {
+  @available(iOS 13.0, macOS 10.15, *)
+  func pigeonDefaultConstructor(pigeonApi: PigeonApiWKWebpagePreferences) throws
+    -> WKWebpagePreferences
+  {
+    return WKWebpagePreferences()
+  }
+
   @available(iOS 13.0, macOS 10.15, *)
   func setAllowsContentJavaScript(
     pigeonApi: PigeonApiWKWebpagePreferences, pigeonInstance: WKWebpagePreferences, allow: Bool

packages/webview_flutter/webview_flutter_wkwebview/lib/src/common/web_kit.g.dart

@@ -3698,7 +3698,7 @@ class WKWebViewConfiguration extends NSObject {
   }
 
   /// The default preferences to use when loading and rendering content.
-  Future<WKWebpagePreferences> getDefaultWebpagePreferences() async {
+  Future<WKWebpagePreferences?> getDefaultWebpagePreferences() async {
     final _PigeonInternalProxyApiBaseCodec pigeonChannelCodec =
         _pigeonVar_codecWKWebViewConfiguration;
     final BinaryMessenger? pigeonVar_binaryMessenger = pigeon_binaryMessenger;
@@ -3722,13 +3722,39 @@ class WKWebViewConfiguration extends NSObject {
         message: pigeonVar_replyList[1] as String?,
         details: pigeonVar_replyList[2],
       );
-    } else if (pigeonVar_replyList[0] == null) {
+    } else {
+      return (pigeonVar_replyList[0] as WKWebpagePreferences?);
+    }
+  }
+
+  /// The default preferences to use when loading and rendering content.
+  Future<void> setDefaultWebpagePreferences(
+      WKWebpagePreferences preferences) async {
+    final _PigeonInternalProxyApiBaseCodec pigeonChannelCodec =
+        _pigeonVar_codecWKWebViewConfiguration;
+    final BinaryMessenger? pigeonVar_binaryMessenger = pigeon_binaryMessenger;
+    const String pigeonVar_channelName =
+        'dev.flutter.pigeon.webview_flutter_wkwebview.WKWebViewConfiguration.setDefaultWebpagePreferences';
+    final BasicMessageChannel<Object?> pigeonVar_channel =
+        BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final Future<Object?> pigeonVar_sendFuture =
+        pigeonVar_channel.send(<Object?>[this, preferences]);
+    final List<Object?>? pigeonVar_replyList =
+        await pigeonVar_sendFuture as List<Object?>?;
+    if (pigeonVar_replyList == null) {
+      throw _createConnectionError(pigeonVar_channelName);
+    } else if (pigeonVar_replyList.length > 1) {
       throw PlatformException(
-        code: 'null-error',
-        message: 'Host platform returned null value for non-null return value.',
+        code: pigeonVar_replyList[0]! as String,
+        message: pigeonVar_replyList[1] as String?,
+        details: pigeonVar_replyList[2],
       );
     } else {
-      return (pigeonVar_replyList[0] as WKWebpagePreferences?)!;
+      return;
     }
   }
 
@@ -8202,6 +8228,44 @@ class URL extends NSObject {
 ///
 /// See https://developer.apple.com/documentation/webkit/wkwebpagepreferences.
 class WKWebpagePreferences extends NSObject {
+  /// Creates a `WKWebpagePreferences`.
+  WKWebpagePreferences({
+    super.pigeon_binaryMessenger,
+    super.pigeon_instanceManager,
+    super.observeValue,
+  }) : super.pigeon_detached() {
+    final int pigeonVar_instanceIdentifier =
+        pigeon_instanceManager.addDartCreatedInstance(this);
+    final _PigeonInternalProxyApiBaseCodec pigeonChannelCodec =
+        _pigeonVar_codecWKWebpagePreferences;
+    final BinaryMessenger? pigeonVar_binaryMessenger = pigeon_binaryMessenger;
+    const String pigeonVar_channelName =
+        'dev.flutter.pigeon.webview_flutter_wkwebview.WKWebpagePreferences.pigeon_defaultConstructor';
+    final BasicMessageChannel<Object?> pigeonVar_channel =
+        BasicMessageChannel<Object?>(
+      pigeonVar_channelName,
+      pigeonChannelCodec,
+      binaryMessenger: pigeonVar_binaryMessenger,
+    );
+    final Future<Object?> pigeonVar_sendFuture =
+        pigeonVar_channel.send(<Object?>[pigeonVar_instanceIdentifier]);
+    () async {
+      final List<Object?>? pigeonVar_replyList =
+          await pigeonVar_sendFuture as List<Object?>?;
+      if (pigeonVar_replyList == null) {
+        throw _createConnectionError(pigeonVar_channelName);
+      } else if (pigeonVar_replyList.length > 1) {
+        throw PlatformException(
+          code: pigeonVar_replyList[0]! as String,
+          message: pigeonVar_replyList[1] as String?,
+          details: pigeonVar_replyList[2],
+        );
+      } else {
+        return;
+      }
+    }();
+  }
+
   /// Constructs [WKWebpagePreferences] without creating the associated native object.
   ///
   /// This should only be used by subclasses created by this library or to

packages/webview_flutter/webview_flutter_wkwebview/lib/src/legacy/web_kit_webview_widget.dart

@@ -512,8 +512,14 @@ class WebKitWebViewPlatformController extends WebViewPlatformController {
   Future<void> _setJavaScriptMode(JavascriptMode mode) async {
     // Attempt to set the value that requires iOS 14+.
     try {
-      final WKWebpagePreferences webpagePreferences =
+      WKWebpagePreferences? webpagePreferences =
           await webView.configuration.getDefaultWebpagePreferences();
+      if (webpagePreferences == null) {
+        webpagePreferences = webViewProxy.createWebpagePreferences();
+        unawaited(webView.configuration.setDefaultWebpagePreferences(
+          webpagePreferences,
+        ));
+      }
       switch (mode) {
         case JavascriptMode.disabled:
           await webpagePreferences.setAllowsContentJavaScript(false);
@@ -769,4 +775,9 @@ class WebViewWidgetProxy {
       didReceiveAuthenticationChallenge: didReceiveAuthenticationChallenge,
     );
   }
+
+  /// Constructs a [WKWebpagePreferences].
+  WKWebpagePreferences createWebpagePreferences() {
+    return WKWebpagePreferences();
+  }
 }

packages/webview_flutter/webview_flutter_wkwebview/lib/src/webkit_proxy.dart

@@ -31,6 +31,7 @@ class WebKitProxy {
     this.newPlatformWebView = PlatformWebView.new,
     this.newWKUIDelegate = WKUIDelegate.new,
     this.newUIScrollViewDelegate = UIScrollViewDelegate.new,
+    this.newWKWebpagePreferences = WKWebpagePreferences.new,
     this.createAsyncAuthenticationChallengeResponse =
         AuthenticationChallengeResponse.createAsync,
     this.withUserAsyncURLCredential = URLCredential.withUserAsync,
@@ -187,6 +188,9 @@ class WebKitProxy {
     )? scrollViewDidScroll,
   }) newUIScrollViewDelegate;
 
+  /// Constructs [WKWebpagePreferences].
+  final WKWebpagePreferences Function() newWKWebpagePreferences;
+
   /// Calls to [AuthenticationChallengeResponse.createAsync].
   final Future<AuthenticationChallengeResponse> Function(
     UrlSessionAuthChallengeDisposition disposition,

packages/webview_flutter/webview_flutter_wkwebview/lib/src/webkit_webview_controller.dart

@@ -619,8 +619,15 @@ class WebKitWebViewController extends PlatformWebViewController {
   Future<void> setJavaScriptMode(JavaScriptMode javaScriptMode) async {
     // Attempt to set the value that requires iOS 14+.
     try {
-      final WKWebpagePreferences webpagePreferences =
+      WKWebpagePreferences? webpagePreferences =
           await _webView.configuration.getDefaultWebpagePreferences();
+      if (webpagePreferences == null) {
+        webpagePreferences =
+            _webKitParams.webKitProxy.newWKWebpagePreferences();
+        unawaited(_webView.configuration.setDefaultWebpagePreferences(
+          webpagePreferences,
+        ));
+      }
       switch (javaScriptMode) {
         case JavaScriptMode.disabled:
           await webpagePreferences.setAllowsContentJavaScript(false);

packages/webview_flutter/webview_flutter_wkwebview/pigeons/web_kit.dart

@@ -711,7 +711,10 @@ abstract class WKWebViewConfiguration extends NSObject {
   void setMediaTypesRequiringUserActionForPlayback(AudiovisualMediaType type);
 
   /// The default preferences to use when loading and rendering content.
-  WKWebpagePreferences getDefaultWebpagePreferences();
+  WKWebpagePreferences? getDefaultWebpagePreferences();
+
+  /// The default preferences to use when loading and rendering content.
+  void setDefaultWebpagePreferences(WKWebpagePreferences preferences);
 }
 
 /// An object for managing interactions between JavaScript code and your web
@@ -1213,6 +1216,9 @@ abstract class URL extends NSObject {
   ),
 )
 abstract class WKWebpagePreferences extends NSObject {
+  /// Creates a `WKWebpagePreferences`.
+  WKWebpagePreferences();
+
   /// A Boolean value that indicates whether JavaScript from web content is
   /// allowed to run.
   void setAllowsContentJavaScript(bool allow);

packages/webview_flutter/webview_flutter_wkwebview/pubspec.yaml

@@ -2,7 +2,7 @@ name: webview_flutter_wkwebview
 description: A Flutter plugin that provides a WebView widget based on Apple's WKWebView control.
 repository: https://github.com/flutter/packages/tree/main/packages/webview_flutter/webview_flutter_wkwebview
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+webview%22
-version: 3.22.0
+version: 3.22.1
 
 environment:
   sdk: ^3.5.0