Include initial offset when using PlatformViewSurface (#114103)

* add position to layout creation

* make position nullable

* fix tests

* test

* clear test size

* clear device pixel ratio

* add more documentaiton

* add comment about localToGlobal

Author: bparrishMines

packages/flutter/lib/src/rendering/platform_view.dart

@@ -192,7 +192,7 @@ class RenderAndroidView extends PlatformViewRenderBox {
     markNeedsPaint();
   }
 
-  // Sets the offset of the underlaying platform view on the platform side.
+  // Sets the offset of the underlying platform view on the platform side.
   //
   // This allows the Android native view to draw the a11y highlights in the same
   // location on the screen as the platform view widget in the Flutter framework.

packages/flutter/lib/src/services/platform_views.dart

@@ -779,7 +779,7 @@ abstract class AndroidViewController extends PlatformViewController {
   ///
   /// If [_createRequiresSize] is true, `size` is non-nullable, and the call
   /// should instead be deferred until the size is available.
-  Future<void> _sendCreateMessage({required covariant Size? size});
+  Future<void> _sendCreateMessage({required covariant Size? size, Offset? position});
 
   /// Sends the message to resize the platform view to [size].
   Future<Size> _sendResizeMessage(Size size);
@@ -788,7 +788,7 @@ abstract class AndroidViewController extends PlatformViewController {
   bool get awaitingCreation => _state == _AndroidViewState.waitingForSize;
 
   @override
-  Future<void> create({Size? size}) async {
+  Future<void> create({Size? size, Offset? position}) async {
     assert(_state != _AndroidViewState.disposed, 'trying to create a disposed Android view');
     assert(_state == _AndroidViewState.waitingForSize, 'Android view is already sized. View id: $viewId');
 
@@ -798,7 +798,7 @@ abstract class AndroidViewController extends PlatformViewController {
     }
 
     _state = _AndroidViewState.creating;
-    await _sendCreateMessage(size: size);
+    await _sendCreateMessage(size: size, position: position);
     _state = _AndroidViewState.created;
 
     for (final PlatformViewCreatedCallback callback in _platformViewCreatedCallbacks) {
@@ -1011,7 +1011,7 @@ class SurfaceAndroidViewController extends AndroidViewController {
   bool get _createRequiresSize => true;
 
   @override
-  Future<bool> _sendCreateMessage({required Size size}) async {
+  Future<bool> _sendCreateMessage({required Size size, Offset? position}) async {
     assert(!size.isEmpty, 'trying to create $TextureAndroidViewController without setting a valid size.');
 
     final dynamic response = await _AndroidViewControllerInternals.sendCreateMessage(
@@ -1022,6 +1022,7 @@ class SurfaceAndroidViewController extends AndroidViewController {
       layoutDirection: _layoutDirection,
       creationParams: _creationParams,
       size: size,
+      position: position,
     );
     if (response is int) {
       (_internals as _TextureAndroidViewControllerInternals).textureId = response;
@@ -1076,13 +1077,14 @@ class ExpensiveAndroidViewController extends AndroidViewController {
   bool get _createRequiresSize => false;
 
   @override
-  Future<void> _sendCreateMessage({required Size? size}) async {
+  Future<void> _sendCreateMessage({required Size? size, Offset? position}) async {
     await _AndroidViewControllerInternals.sendCreateMessage(
       viewId: viewId,
       viewType: _viewType,
       hybrid: true,
       layoutDirection: _layoutDirection,
       creationParams: _creationParams,
+      position: position,
     );
   }
 
@@ -1133,7 +1135,7 @@ class TextureAndroidViewController extends AndroidViewController {
   bool get _createRequiresSize => true;
 
   @override
-  Future<void> _sendCreateMessage({required Size size}) async {
+  Future<void> _sendCreateMessage({required Size size, Offset? position}) async {
     assert(!size.isEmpty, 'trying to create $TextureAndroidViewController without setting a valid size.');
 
     _internals.textureId = await _AndroidViewControllerInternals.sendCreateMessage(
@@ -1143,6 +1145,7 @@ class TextureAndroidViewController extends AndroidViewController {
       layoutDirection: _layoutDirection,
       creationParams: _creationParams,
       size: size,
+      position: position,
     ) as int;
   }
 
@@ -1190,7 +1193,8 @@ abstract class _AndroidViewControllerInternals {
       required bool hybrid,
       bool hybridFallback = false,
       _CreationParams? creationParams,
-      Size? size}) {
+      Size? size,
+      Offset? position}) {
     final Map<String, dynamic> args = <String, dynamic>{
       'id': viewId,
       'viewType': viewType,
@@ -1199,6 +1203,8 @@ abstract class _AndroidViewControllerInternals {
       if (size != null) 'width': size.width,
       if (size != null) 'height': size.height,
       if (hybridFallback == true) 'hybridFallback': hybridFallback,
+      if (position != null) 'left': position.dx,
+      if (position != null) 'top': position.dy,
     };
     if (creationParams != null) {
       final ByteData paramsByteData = creationParams.codec.encodeMessage(creationParams.data)!;
@@ -1449,7 +1455,11 @@ abstract class PlatformViewController {
   /// [size] is the view's initial size in logical pixel.
   /// [size] can be omitted if the concrete implementation doesn't require an initial size
   /// to create the platform view.
-  Future<void> create({Size? size}) async {}
+  ///
+  /// [position] is the view's initial position in logical pixels.
+  /// [position] can be omitted if the concrete implementation doesn't require
+  /// an initial position.
+  Future<void> create({Size? size, Offset? position}) async {}
 
   /// Disposes the platform view.
   ///

packages/flutter/lib/src/widgets/platform_view.dart

@@ -5,6 +5,7 @@
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
+import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';
 
 import 'basic.dart';
@@ -879,9 +880,9 @@ class _PlatformViewLinkState extends State<PlatformViewLink> {
     if (!_platformViewCreated) {
       // Depending on the implementation, the first non-empty size can be used
       // to size the platform view.
-      return _PlatformViewPlaceHolder(onLayout: (Size size) {
+      return _PlatformViewPlaceHolder(onLayout: (Size size, Offset position) {
         if (controller.awaitingCreation && !size.isEmpty) {
-          controller.create(size: size);
+          controller.create(size: size, position: position);
         }
       });
     }
@@ -1188,7 +1189,7 @@ class _PlatformLayerBasedAndroidViewSurface extends PlatformViewSurface {
 
 /// A callback used to notify the size of the platform view placeholder.
 /// This size is the initial size of the platform view.
-typedef _OnLayoutCallback = void Function(Size size);
+typedef _OnLayoutCallback = void Function(Size size, Offset position);
 
 /// A [RenderBox] that notifies its size to the owner after a layout.
 class _PlatformViewPlaceholderBox extends RenderConstrainedBox {
@@ -1204,7 +1205,10 @@ class _PlatformViewPlaceholderBox extends RenderConstrainedBox {
   @override
   void performLayout() {
     super.performLayout();
-    onLayout(size);
+    // A call to `localToGlobal` requires waiting for a frame to render first.
+    SchedulerBinding.instance.addPostFrameCallback((_) {
+      onLayout(size, localToGlobal(Offset.zero));
+    });
   }
 }
 

packages/flutter/test/services/fake_platform_views.dart

@@ -60,6 +60,8 @@ class FakeAndroidViewController implements AndroidViewController {
 
   bool _createCalledSuccessfully = false;
 
+  Offset? createPosition;
+
   final List<PlatformViewCreatedCallback> _createdCallbacks = <PlatformViewCreatedCallback>[];
 
   /// Events that are dispatched.
@@ -131,12 +133,13 @@ class FakeAndroidViewController implements AndroidViewController {
   }
 
   @override
-  Future<void> create({Size? size}) async {
+  Future<void> create({Size? size, Offset? position}) async {
     assert(!_createCalledSuccessfully);
     if (requiresSize && size != null) {
       assert(!size.isEmpty);
     }
-    _createCalledSuccessfully = size != null || !requiresSize;
+    _createCalledSuccessfully = size != null && position != null || !requiresSize;
+    createPosition = position;
   }
 
   @override
@@ -214,6 +217,8 @@ class FakeAndroidPlatformViewsController {
     final bool? hybrid = args['hybrid'] as bool?;
     final bool? hybridFallback = args['hybridFallback'] as bool?;
     final Uint8List? creationParams = args['params'] as Uint8List?;
+    final double? top = args['top'] as double?;
+    final double? left = args['left'] as double?;
 
     if (_views.containsKey(id)) {
       throw PlatformException(
@@ -239,6 +244,7 @@ class FakeAndroidPlatformViewsController {
         hybrid: hybrid,
         hybridFallback: hybridFallback,
         creationParams: creationParams,
+        position: left != null && top != null ? Offset(left, top) : null,
     );
     // Return a hybrid result (null rather than a texture ID) if:
     final bool hybridResult =
@@ -538,7 +544,7 @@ class FakeHtmlPlatformViewsController {
 @immutable
 class FakeAndroidPlatformView {
   const FakeAndroidPlatformView(this.id, this.type, this.size, this.layoutDirection,
-    {this.hybrid, this.hybridFallback, this.creationParams});
+    {this.hybrid, this.hybridFallback, this.creationParams, this.position});
 
   final int id;
   final String type;
@@ -547,6 +553,7 @@ class FakeAndroidPlatformView {
   final int layoutDirection;
   final bool? hybrid;
   final bool? hybridFallback;
+  final Offset? position;
 
   FakeAndroidPlatformView copyWith({Size? size, int? layoutDirection}) => FakeAndroidPlatformView(
     id,
@@ -556,6 +563,7 @@ class FakeAndroidPlatformView {
     hybrid: hybrid,
     hybridFallback: hybridFallback,
     creationParams: creationParams,
+    position: position,
   );
 
   @override
@@ -570,7 +578,8 @@ class FakeAndroidPlatformView {
         && other.size == size
         && other.hybrid == hybrid
         && other.hybridFallback == hybridFallback
-        && other.layoutDirection == layoutDirection;
+        && other.layoutDirection == layoutDirection
+        && other.position == position;
   }
 
   @override
@@ -582,13 +591,14 @@ class FakeAndroidPlatformView {
     layoutDirection,
     hybrid,
     hybridFallback,
+    position,
   );
 
   @override
   String toString() {
     return 'FakeAndroidPlatformView(id: $id, type: $type, size: $size, '
       'layoutDirection: $layoutDirection, hybrid: $hybrid, '
-      'hybridFallback: $hybridFallback, creationParams: $creationParams)';
+      'hybridFallback: $hybridFallback, creationParams: $creationParams, position: $position)';
   }
 }
 

packages/flutter/test/widgets/platform_view_test.dart

@@ -2599,6 +2599,51 @@ void main() {
       },
     );
 
+    testWidgets('PlatformViewLink includes offset in create call when using texture layer', (WidgetTester tester) async {
+      late FakeAndroidViewController controller;
+
+      final PlatformViewLink platformViewLink = PlatformViewLink(
+        viewType: 'webview',
+        onCreatePlatformView: (PlatformViewCreationParams params) {
+          controller = FakeAndroidViewController(params.id, requiresSize: true);
+          controller.create();
+          // This test should be simulating one of the texture-based display
+          // modes, where `create` is a no-op when not provided a size, and
+          // creation is triggered via a later call to setSize, or to `create`
+          // with a size.
+          expect(controller.awaitingCreation, true);
+          return controller;
+        },
+        surfaceFactory: (BuildContext context, PlatformViewController controller) {
+          return PlatformViewSurface(
+            gestureRecognizers: const <Factory<OneSequenceGestureRecognizer>>{},
+            controller: controller,
+            hitTestBehavior: PlatformViewHitTestBehavior.opaque,
+          );
+        },
+      );
+
+      TestWidgetsFlutterBinding.instance.window.physicalSizeTestValue = const Size(400, 200);
+      TestWidgetsFlutterBinding.instance.window.devicePixelRatioTestValue = 1.0;
+
+      await tester.pumpWidget(
+        Container(
+          constraints: const BoxConstraints.expand(),
+          alignment: Alignment.center,
+          child: SizedBox(
+            width: 100,
+            height: 50,
+            child: platformViewLink,
+          ),
+        )
+      );
+
+      expect(controller.createPosition, const Offset(150, 75));
+
+      TestWidgetsFlutterBinding.instance.window.clearPhysicalSizeTestValue();
+      TestWidgetsFlutterBinding.instance.window.clearDevicePixelRatioTestValue();
+    });
+
     testWidgets(
       'PlatformViewLink does not double-call create for Android Hybrid Composition',
       (WidgetTester tester) async {
@@ -2616,7 +2661,7 @@ void main() {
             controller = FakeAndroidViewController(params.id);
             controller.create();
             // This test should be simulating Hybrid Composition mode, where
-            // `create` takes effect immidately.
+            // `create` takes effect immediately.
             expect(controller.awaitingCreation, false);
             return controller;
           },