feature: implemented modifyRegular + fixed a bug where a widget tree was mandatory on accident

Author: mattkae

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

@@ -42,24 +42,22 @@ abstract class WindowController with ChangeNotifier {
           _size = metadata.size;
           notifyListeners();
 
-          SchedulerBinding.instance.addPostFrameCallback((_) async {
-            _listener = _WindowListener(
-              viewId: metadata.view.viewId,
-              onChanged: (_WindowChangeProperties properties) {
-                if (properties.size != null) {
-                  _size = properties.size!;
-                  notifyListeners();
-                }
-              },
-              onDestroyed: () {
-                _view = null;
-                _isPendingDestroy = false;
+          _listener = _WindowListener(
+            viewId: metadata.view.viewId,
+            onChanged: (_WindowChangeProperties properties) {
+              if (properties.size != null) {
+                _size = properties.size!;
                 notifyListeners();
-                onDestroyed?.call();
-              },
-            );
-            _WindowingAppGlobalData.instance._listen(_listener);
-          });
+              }
+            },
+            onDestroyed: () {
+              _view = null;
+              _isPendingDestroy = false;
+              notifyListeners();
+              onDestroyed?.call();
+            },
+          );
+          _WindowingAppGlobalData.instance._listen(_listener);
         })
         .catchError((Object? error) {
           onError?.call(error.toString());
@@ -138,8 +136,12 @@ class RegularWindowController extends WindowController {
   WindowArchetype get type => WindowArchetype.regular;
 
   /// Modify the properties of the window.
-  Future<void> modify({Size? size}) {
-    throw UnimplementedError();
+  /// [size] the new size of the window
+  /// [title] the new title of the window
+  /// [state] the new state of the window
+  Future<void> modify({Size? size, String? title, WindowState? state}) {
+    assert(isReady, 'Window is not ready');
+    return _modifyRegular(viewId: view.viewId, size: size, title: title, state: state);
   }
 }
 
@@ -266,6 +268,16 @@ Future<_WindowCreationResult> _createRegular({
   );
 }
 
+Future<void> _modifyRegular({required int viewId, Size? size, String? title, WindowState? state}) {
+  assert(size != null || title != null || state != null);
+  return SystemChannels.windowing.invokeMethod('modifyRegular', <String, dynamic>{
+    'viewId': viewId,
+    'size': size != null ? <double>[size.width, size.height] : null,
+    'title': title,
+    'state': state?.toString(),
+  });
+}
+
 Future<_WindowCreationResult> _createWindow({
   required WindowArchetype archetype,
   required Future<Map<Object?, Object?>> Function(MethodChannel channel) viewBuilder,

packages/flutter/test/widgets/window_test.dart

@@ -6,14 +6,22 @@ import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/flutter_test.dart';
 
-Future<Object?>? Function(MethodCall)? _createWindowMethodCallHandler(WidgetTester tester) {
+import '../rendering/proxy_box_test.dart';
+
+Future<Object?>? Function(MethodCall)? _createWindowMethodCallHandler({
+  required WidgetTester tester,
+  void Function(MethodCall)? onMethodCall,
+}) {
   return (MethodCall call) async {
+    onMethodCall?.call(call);
     final Map<Object?, Object?> args = call.arguments as Map<Object?, Object?>;
     if (call.method == 'createWindow') {
       final List<Object?> size = args['size']! as List<Object?>;
       final String state = args['state'] as String? ?? WindowState.restored.toString();
 
       return <String, Object?>{'viewId': tester.view.viewId, 'size': size, 'state': state};
+    } else if (call.method == 'modifyRegular') {
+      return null;
     } else if (call.method == 'destroyWindow') {
       await tester.binding.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.windowing.name,
@@ -38,18 +46,10 @@ void main() {
 
     tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
       SystemChannels.windowing,
-      _createWindowMethodCallHandler(tester),
+      _createWindowMethodCallHandler(tester: tester),
     );
 
     final RegularWindowController controller = RegularWindowController(size: windowSize);
-    await tester.pumpWidget(
-      wrapWithView: false,
-      Builder(
-        builder: (BuildContext context) {
-          return RegularWindow(controller: controller, child: Container());
-        },
-      ),
-    );
 
     await tester.pump();
 
@@ -89,7 +89,7 @@ void main() {
 
     tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
       SystemChannels.windowing,
-      _createWindowMethodCallHandler(tester),
+      _createWindowMethodCallHandler(tester: tester),
     );
 
     bool destroyed = false;
@@ -123,19 +123,10 @@ void main() {
 
       tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
         SystemChannels.windowing,
-        _createWindowMethodCallHandler(tester),
+        _createWindowMethodCallHandler(tester: tester),
       );
 
       final RegularWindowController controller = RegularWindowController(size: initialSize);
-      await tester.pumpWidget(
-        wrapWithView: false,
-        Builder(
-          builder: (BuildContext context) {
-            return RegularWindow(controller: controller, child: Container());
-          },
-        ),
-      );
-
       await tester.pump();
 
       await tester.binding.defaultBinaryMessenger.handlePlatformMessage(
@@ -153,4 +144,140 @@ void main() {
       expect(controller.size, newSize);
     },
   );
+
+  testWidgets('RegularWindowController.modify can be called when provided with a "size" argument', (
+    WidgetTester tester,
+  ) async {
+    const Size initialSize = Size(800, 600);
+    const Size newSize = Size(400, 300);
+
+    bool wasCalled = false;
+    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+      SystemChannels.windowing,
+      _createWindowMethodCallHandler(
+        tester: tester,
+        onMethodCall: (MethodCall call) {
+          if (call.method != 'modifyRegular') {
+            return;
+          }
+
+          final Map<Object?, Object?> args = call.arguments as Map<Object?, Object?>;
+          final int viewId = args['viewId']! as int;
+          final List<Object?>? size = args['size'] as List<Object?>?;
+          final String? title = args['title'] as String?;
+          final String? state = args['state'] as String?;
+          expect(viewId, tester.view.viewId);
+          expect(size, <double>[newSize.width, newSize.height]);
+          expect(title, null);
+          expect(state, null);
+          wasCalled = true;
+        },
+      ),
+    );
+
+    final RegularWindowController controller = RegularWindowController(size: initialSize);
+    await tester.pump();
+
+    await controller.modify(size: newSize);
+    await tester.pump();
+
+    expect(wasCalled, true);
+  });
+
+  testWidgets(
+    'RegularWindowController.modify can be called when provided with a "title" argument',
+    (WidgetTester tester) async {
+      const Size initialSize = Size(800, 600);
+      const String newTitle = 'New Title';
+
+      bool wasCalled = false;
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        SystemChannels.windowing,
+        _createWindowMethodCallHandler(
+          tester: tester,
+          onMethodCall: (MethodCall call) {
+            if (call.method != 'modifyRegular') {
+              return;
+            }
+
+            final Map<Object?, Object?> args = call.arguments as Map<Object?, Object?>;
+            final int viewId = args['viewId']! as int;
+            final List<Object?>? size = args['size'] as List<Object?>?;
+            final String? title = args['title'] as String?;
+            final String? state = args['state'] as String?;
+            expect(viewId, tester.view.viewId);
+            expect(size, null);
+            expect(title, newTitle);
+            expect(state, null);
+            wasCalled = true;
+          },
+        ),
+      );
+
+      final RegularWindowController controller = RegularWindowController(size: initialSize);
+      await tester.pump();
+
+      await controller.modify(title: newTitle);
+      await tester.pump();
+
+      expect(wasCalled, true);
+    },
+  );
+
+  testWidgets(
+    'RegularWindowController.modify can be called when provided with a "state" argument',
+    (WidgetTester tester) async {
+      const Size initialSize = Size(800, 600);
+      const WindowState newState = WindowState.minimized;
+
+      bool wasCalled = false;
+      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        SystemChannels.windowing,
+        _createWindowMethodCallHandler(
+          tester: tester,
+          onMethodCall: (MethodCall call) {
+            if (call.method != 'modifyRegular') {
+              return;
+            }
+
+            final Map<Object?, Object?> args = call.arguments as Map<Object?, Object?>;
+            final int viewId = args['viewId']! as int;
+            final List<Object?>? size = args['size'] as List<Object?>?;
+            final String? title = args['title'] as String?;
+            final String? state = args['state'] as String?;
+            expect(viewId, tester.view.viewId);
+            expect(size, null);
+            expect(title, null);
+            expect(state, newState.toString());
+            wasCalled = true;
+          },
+        ),
+      );
+
+      final RegularWindowController controller = RegularWindowController(size: initialSize);
+      await tester.pump();
+
+      await controller.modify(state: newState);
+      await tester.pump();
+
+      expect(wasCalled, true);
+    },
+  );
+
+  testWidgets('RegularWindowController.modify throws when no arguments are provided', (
+    WidgetTester tester,
+  ) async {
+    const Size initialSize = Size(800, 600);
+    const WindowState newState = WindowState.minimized;
+
+    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+      SystemChannels.windowing,
+      _createWindowMethodCallHandler(tester: tester),
+    );
+
+    final RegularWindowController controller = RegularWindowController(size: initialSize);
+    await tester.pump();
+
+    expect(() async => controller.modify(), throwsA(isA<AssertionError>()));
+  });
 }