Make dart low-level code for offset changes listener mirror the Andro…

…id API closely

packages/webview_flutter/webview_flutter_android/android/src/main/java/io/flutter/plugins/webviewflutter/GeneratedAndroidWebView.java

@@ -1575,6 +1575,21 @@ public void create(@NonNull Long identifierArg, @NonNull Reply<Void> callback) {
           new ArrayList<Object>(Collections.singletonList(identifierArg)),
           channelReply -> callback.reply(null));
     }
+
+    public void onScrollChanged(
+        @NonNull Long webViewInstanceIdArg,
+        @NonNull Long xArg,
+        @NonNull Long yArg,
+        @NonNull Long oldXArg,
+        @NonNull Long oldYArg,
+        @NonNull Reply<Void> callback) {
+      BasicMessageChannel<Object> channel =
+          new BasicMessageChannel<>(
+              binaryMessenger, "dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged", getCodec());
+      channel.send(
+          new ArrayList<Object>(Arrays.asList(webViewInstanceIdArg, xArg, yArg, oldXArg, oldYArg)),
+          channelReply -> callback.reply(null));
+    }
   }
   /** Generated interface from Pigeon that represents a handler of messages from Flutter. */
   public interface WebSettingsHostApi {

packages/webview_flutter/webview_flutter_android/android/src/main/java/io/flutter/plugins/webviewflutter/WebViewFlutterApiImpl.java

@@ -60,13 +60,17 @@ void setApi(@NonNull WebViewFlutterApi api) {
 
   public void onScrollChanged(
       @NonNull WebView instance,
-      @NonNull Long xArg,
-      @NonNull Long yArg,
+      @NonNull Long x,
+      @NonNull Long y,
+      @NonNull Long oldX,
+      @NonNull Long oldY,
       @NonNull WebViewFlutterApi.Reply<Void> callback) {
-    api.onScrollPosChange(
+    api.onScrollChanged(
         Objects.requireNonNull(instanceManager.getIdentifierForStrongReference(instance)),
-        xArg,
-        yArg,
+        x,
+        y,
+        oldX,
+        oldY,
         callback);
   }
 }

packages/webview_flutter/webview_flutter_android/android/src/main/java/io/flutter/plugins/webviewflutter/WebViewHostApiImpl.java

@@ -157,10 +157,10 @@ public WebChromeClient getWebChromeClient() {
     }
 
     @Override
-    protected void onScrollChanged(int l, int t, int oldL, int oldT) {
-      super.onScrollChanged(l, t, oldL, oldT);
+    protected void onScrollChanged(int left, int top, int oldLeft, int oldTop) {
+      super.onScrollChanged(left, top, oldLeft, oldTop);
       api.onScrollChanged(
-          this, (long) l, (long) t, reply -> {});
+          this, (long) left, (long) top, (long) oldLeft, (long) oldTop, reply -> {});
     }
 
     /**

packages/webview_flutter/webview_flutter_android/android/src/test/java/io/flutter/plugins/webviewflutter/WebViewTest.java

@@ -368,12 +368,12 @@ public void onScrollChanged() {
     flutterApiImpl.setApi(mockFlutterApi);
     flutterApiImpl.create(mockWebView, reply -> {});
 
-    flutterApiImpl.onScrollChanged(mockWebView, 0L, 1L, reply -> {});
+    flutterApiImpl.onScrollChanged(mockWebView, 0L, 1L, 2L, 3L, reply -> {});
 
     final long instanceIdentifier =
         Objects.requireNonNull(instanceManager.getIdentifierForStrongReference(mockWebView));
     verify(mockFlutterApi)
-        .onScrollPosChange(eq(instanceIdentifier), eq(0L), eq(1L), any());
+        .onScrollChanged(eq(instanceIdentifier), eq(0L), eq(1L), eq(2L), eq(3L), any());
 
     instanceManager.stopFinalizationListener();
   }

packages/webview_flutter/webview_flutter_android/example/integration_test/webview_flutter_test.dart

@@ -684,7 +684,8 @@ Future<void> main() async {
           base64Encode(const Utf8Encoder().convert(scrollTestPage));
 
       final Completer<void> pageLoaded = Completer<void>();
-      Completer<ContentOffsetChange> offsetsCompleter = Completer<ContentOffsetChange>();
+      Completer<ContentOffsetChange> offsetsCompleter =
+          Completer<ContentOffsetChange>();
       final PlatformWebViewController controller = PlatformWebViewController(
         const PlatformWebViewControllerCreationParams(),
       )
@@ -701,9 +702,7 @@ Future<void> main() async {
             ),
           ),
         )
-        ..setOnContentOffsetChanged(
-            (ContentOffsetChange contentOffsetChange) {
-              print('comppp $contentOffsetChange');
+        ..setOnContentOffsetChanged((ContentOffsetChange contentOffsetChange) {
           offsetsCompleter.complete(contentOffsetChange);
         });
 
@@ -734,16 +733,22 @@ Future<void> main() async {
       expect(scrollPos.dx, X_SCROLL);
       expect(scrollPos.dy, Y_SCROLL);
       await expectLater(
-          offsetsCompleter.future.then((ContentOffsetChange contentOffsetChange) => <int>[contentOffsetChange.x, contentOffsetChange.y]), completion(<int>[X_SCROLL, Y_SCROLL]));
-
+          offsetsCompleter.future.then(
+              (ContentOffsetChange contentOffsetChange) =>
+                  <int>[contentOffsetChange.x, contentOffsetChange.y]),
+          completion(<int>[X_SCROLL, Y_SCROLL]));
+
       // Check scrollBy() (on top of scrollTo())
       offsetsCompleter = Completer<ContentOffsetChange>();
       await controller.scrollBy(X_SCROLL, Y_SCROLL);
       scrollPos = await controller.getScrollPosition();
       expect(scrollPos.dx, X_SCROLL * 2);
       expect(scrollPos.dy, Y_SCROLL * 2);
       await expectLater(
-          offsetsCompleter.future.then((ContentOffsetChange contentOffsetChange) => <int>[contentOffsetChange.x, contentOffsetChange.y]), completion(<int>[X_SCROLL * 2, Y_SCROLL * 2]));
+          offsetsCompleter.future.then(
+              (ContentOffsetChange contentOffsetChange) =>
+                  <int>[contentOffsetChange.x, contentOffsetChange.y]),
+          completion(<int>[X_SCROLL * 2, Y_SCROLL * 2]));
     });
   });
 

packages/webview_flutter/webview_flutter_android/lib/src/android_proxy.dart

@@ -28,8 +28,8 @@ class AndroidWebViewProxy {
 
   /// Constructs a [android_webview.WebView].
   final android_webview.WebView Function(
-      {Function(ContentOffsetChange contentOffsetChange)?
-          onScrollChanged}) createAndroidWebView;
+          {Function(ContentOffsetChange contentOffsetChange)? onScrollChanged})
+      createAndroidWebView;
 
   /// Constructs a [android_webview.WebChromeClient].
   final android_webview.WebChromeClient Function({

packages/webview_flutter/webview_flutter_android/lib/src/android_webview.g.dart

@@ -1050,6 +1050,8 @@ abstract class WebViewFlutterApi {
   /// Create a new Dart instance and add it to the `InstanceManager`.
   void create(int identifier);
 
+  void onScrollChanged(int webViewInstanceId, int x, int y, int oldX, int oldY);
+
   static void setup(WebViewFlutterApi? api,
       {BinaryMessenger? binaryMessenger}) {
     {
@@ -1071,6 +1073,38 @@ abstract class WebViewFlutterApi {
         });
       }
     }
+    {
+      final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
+          'dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged', codec,
+          binaryMessenger: binaryMessenger);
+      if (api == null) {
+        channel.setMessageHandler(null);
+      } else {
+        channel.setMessageHandler((Object? message) async {
+          assert(message != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null.');
+          final List<Object?> args = (message as List<Object?>?)!;
+          final int? arg_webViewInstanceId = (args[0] as int?);
+          assert(arg_webViewInstanceId != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null, expected non-null int.');
+          final int? arg_x = (args[1] as int?);
+          assert(arg_x != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null, expected non-null int.');
+          final int? arg_y = (args[2] as int?);
+          assert(arg_y != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null, expected non-null int.');
+          final int? arg_oldX = (args[3] as int?);
+          assert(arg_oldX != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null, expected non-null int.');
+          final int? arg_oldY = (args[4] as int?);
+          assert(arg_oldY != null,
+              'Argument for dev.flutter.pigeon.WebViewFlutterApi.onScrollChanged was null, expected non-null int.');
+          api.onScrollChanged(
+              arg_webViewInstanceId!, arg_x!, arg_y!, arg_oldX!, arg_oldY!);
+          return;
+        });
+      }
+    }
   }
 }
 

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_api_impls.dart

@@ -8,7 +8,8 @@ import 'dart:typed_data';
 import 'dart:ui';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
-import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart' show ContentOffsetChange;
+import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart'
+    show ContentOffsetChange;
 
 import 'android_webview.dart';
 import 'android_webview.g.dart';
@@ -384,8 +385,8 @@ class WebViewFlutterApiImpl implements WebViewFlutterApi {
   }
 
   @override
-  void onScrollPosChange(
-      int webViewInstanceId, int x, int y) {
+  void onScrollChanged(
+      int webViewInstanceId, int x, int y, int oldX, int oldY) {
     final WebView? webViewInstance = instanceManager
         .getInstanceWithWeakReference(webViewInstanceId) as WebView?;
     assert(

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

@@ -105,11 +105,12 @@ class AndroidWebViewController extends PlatformWebViewController {
       _androidWebViewParams.androidWebViewProxy.createAndroidWebView(
           onScrollChanged: withWeakReferenceTo(this,
               (WeakReference<AndroidWebViewController> weakReference) {
-            return (ContentOffsetChange contentOffsetChange) async {
-              final Function(ContentOffsetChange)? callback = weakReference.target?._onContentOffsetChangedCallback;
-              callback?.call(contentOffsetChange);
-            };
-          }));
+    return (ContentOffsetChange contentOffsetChange) async {
+      final Function(ContentOffsetChange)? callback =
+          weakReference.target?._onContentOffsetChangedCallback;
+      callback?.call(contentOffsetChange);
+    };
+  }));
 
   late final android_webview.WebChromeClient _webChromeClient =
       _androidWebViewParams.androidWebViewProxy.createAndroidWebChromeClient(

packages/webview_flutter/webview_flutter_android/pigeons/android_webview.dart

@@ -229,8 +229,7 @@ abstract class WebViewFlutterApi {
   /// Create a new Dart instance and add it to the `InstanceManager`.
   void create(int identifier);
 
-  void onScrollPosChange(
-      int webViewInstanceId, int x, int y);
+  void onScrollChanged(int webViewInstanceId, int x, int y, int oldX, int oldY);
 }
 
 @HostApi(dartHostTestHandler: 'TestWebSettingsHostApi')

packages/webview_flutter/webview_flutter_android/test/android_navigation_delegate_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/android_navigation_delegate_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'package:mockito/mockito.dart' as _i1;
 

packages/webview_flutter/webview_flutter_android/test/android_webview_controller_test.dart

@@ -90,9 +90,11 @@ void main() {
                     )? onPermissionRequest,
                   }) =>
                       MockWebChromeClient(),
-              createAndroidWebView:
-                  ({dynamic Function(ContentOffsetChange contentOffsetChange)? onScrollChanged}) =>
-                      nonNullMockWebView,
+              createAndroidWebView: (
+                      {dynamic Function(
+                              ContentOffsetChange contentOffsetChange)?
+                          onScrollChanged}) =>
+                  nonNullMockWebView,
               createAndroidWebViewClient: ({
                 void Function(android_webview.WebView webView, String url)?
                     onPageFinished,

packages/webview_flutter/webview_flutter_android/test/android_webview_controller_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/android_webview_controller_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'dart:async' as _i9;
 import 'dart:typed_data' as _i14;

packages/webview_flutter/webview_flutter_android/test/android_webview_cookie_manager_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/android_webview_cookie_manager_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'dart:async' as _i5;
 import 'dart:ui' as _i4;
@@ -412,6 +414,17 @@ class MockAndroidWebViewController extends _i1.Mock
         returnValueForMissingStub: _i5.Future<void>.value(),
       ) as _i5.Future<void>);
   @override
+  _i5.Future<void> setOnContentOffsetChanged(
+          void Function(_i3.ContentOffsetChange)? onOffsetChange) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #setOnContentOffsetChanged,
+          [onOffsetChange],
+        ),
+        returnValue: _i5.Future<void>.value(),
+        returnValueForMissingStub: _i5.Future<void>.value(),
+      ) as _i5.Future<void>);
+  @override
   _i5.Future<void> setMediaPlaybackRequiresUserGesture(bool? require) =>
       (super.noSuchMethod(
         Invocation.method(

packages/webview_flutter/webview_flutter_android/test/android_webview_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/android_webview_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'dart:async' as _i5;
 import 'dart:typed_data' as _i7;

packages/webview_flutter/webview_flutter_android/test/instance_manager_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/instance_manager_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'package:mockito/mockito.dart' as _i1;
 

packages/webview_flutter/webview_flutter_android/test/legacy/webview_android_cookie_manager_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/legacy/webview_android_cookie_manager_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'dart:async' as _i3;
 

packages/webview_flutter/webview_flutter_android/test/legacy/webview_android_widget_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in webview_flutter_android/test/legacy/webview_android_widget_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'dart:async' as _i5;
 import 'dart:typed_data' as _i6;