Update ThemeData.dialogTheme type to accept DialogThemeData (#155129)

Following https://github.com/flutter/flutter/pull/153982, this PR is to normalize `ThemeData.dialogTheme`; change the `DialogTheme dialogTheme` property to `DialogThemeData dialogTheme` in ThemeData. In `ThemeData()` and `ThemeData.copyWith()`, the dialogTheme parameter type is changed to `Object?` to accept both `DialogTheme` and `DialogThemeData` so that we won't cause immediate breaking change and make sure rolling is smooth. Once all component themes are normalized, these `Object?` types should be changed to `xxxThemeData`.

There's no way to create a dart fix because we can't add a "@deprecated" label for `DialogTheme`; `DialogTheme` is a new `InheritedWidget` subclass now.

Addresses the "theme normalization" sub project within https://github.com/flutter/flutter/issues/91772

packages/flutter/lib/src/material/date_picker.dart

@@ -707,7 +707,7 @@ class _DatePickerDialogState extends State<DatePickerDialog> with RestorationMix
     // layout issues.
     final double textScaleFactor = MediaQuery.textScalerOf(context).clamp(maxScaleFactor: _kMaxTextScaleFactor).scale(_fontSizeToScale) / _fontSizeToScale;
     final Size dialogSize = _dialogSize(context) * textScaleFactor;
-    final DialogTheme dialogTheme = theme.dialogTheme;
+    final DialogThemeData dialogTheme = theme.dialogTheme;
     return Dialog(
       backgroundColor: datePickerTheme.backgroundColor ?? defaults.backgroundColor,
       elevation: useMaterial3
@@ -1660,7 +1660,7 @@ class _DateRangePickerDialogState extends State<DateRangePickerDialog> with Rest
               : localizations.dateRangePickerHelpText.toUpperCase()
           ),
         );
-        final DialogTheme dialogTheme = theme.dialogTheme;
+        final DialogThemeData dialogTheme = theme.dialogTheme;
         size = orientation == Orientation.portrait
           ? (useMaterial3 ? _inputPortraitDialogSizeM3 : _inputPortraitDialogSizeM2)
           : _inputRangeLandscapeDialogSize;

packages/flutter/lib/src/material/dialog.dart

@@ -230,7 +230,7 @@ class Dialog extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final ThemeData theme = Theme.of(context);
-    final DialogThemeData dialogTheme = DialogTheme.of(context).data;
+    final DialogThemeData dialogTheme = DialogTheme.of(context);
     final EdgeInsets effectivePadding = MediaQuery.viewInsetsOf(context)
       + (insetPadding ?? dialogTheme.insetPadding ?? _defaultInsetPadding);
     final DialogThemeData defaults = theme.useMaterial3
@@ -720,7 +720,7 @@ class AlertDialog extends StatelessWidget {
     assert(debugCheckHasMaterialLocalizations(context));
     final ThemeData theme = Theme.of(context);
 
-    final DialogThemeData dialogTheme = DialogTheme.of(context).data;
+    final DialogThemeData dialogTheme = DialogTheme.of(context);
     final DialogThemeData defaults = theme.useMaterial3 ? _DialogDefaultsM3(context) : _DialogDefaultsM2(context);
 
     String? label = semanticLabel;
@@ -1235,7 +1235,7 @@ class SimpleDialog extends StatelessWidget {
 
     // The paddingScaleFactor is used to adjust the padding of Dialog
     // children.
-    final TextStyle defaultTextStyle = titleTextStyle ?? DialogTheme.of(context).data.titleTextStyle ?? theme.textTheme.titleLarge!;
+    final TextStyle defaultTextStyle = titleTextStyle ?? DialogTheme.of(context).titleTextStyle ?? theme.textTheme.titleLarge!;
     final double fontSize = defaultTextStyle.fontSize ?? kDefaultFontSize;
     final double fontSizeToScale = fontSize == 0.0 ? kDefaultFontSize : fontSize;
     final double effectiveTextScale = MediaQuery.textScalerOf(context).scale(fontSizeToScale) / fontSizeToScale;
@@ -1445,7 +1445,7 @@ Future<T?> showDialog<T>({
     builder: builder,
     barrierColor: barrierColor
       ?? DialogTheme.of(context).barrierColor
-      ?? Theme.of(context).dialogTheme.data.barrierColor
+      ?? Theme.of(context).dialogTheme.barrierColor
       ?? Colors.black54,
     barrierDismissible: barrierDismissible,
     barrierLabel: barrierLabel,

packages/flutter/lib/src/material/dialog_theme.dart

@@ -190,9 +190,9 @@ class DialogTheme extends InheritedTheme with Diagnosticable {
   }
 
   /// The [ThemeData.dialogTheme] property of the ambient [Theme].
-  static DialogTheme of(BuildContext context) {
+  static DialogThemeData of(BuildContext context) {
     final DialogTheme? dialogTheme = context.dependOnInheritedWidgetOfExactType<DialogTheme>();
-    return dialogTheme ?? Theme.of(context).dialogTheme;
+    return dialogTheme?.data ?? Theme.of(context).dialogTheme;
   }
 
   @override

packages/flutter/lib/src/material/theme_data.dart

@@ -320,7 +320,8 @@ class ThemeData with Diagnosticable {
     ChipThemeData? chipTheme,
     DataTableThemeData? dataTableTheme,
     DatePickerThemeData? datePickerTheme,
-    DialogTheme? dialogTheme,
+    // TODO(QuncCccccc): Change the parameter type to DialogThemeData
+    Object? dialogTheme,
     DividerThemeData? dividerTheme,
     DrawerThemeData? drawerTheme,
     DropdownMenuThemeData? dropdownMenuTheme,
@@ -497,7 +498,15 @@ class ThemeData with Diagnosticable {
     chipTheme ??= const ChipThemeData();
     dataTableTheme ??= const DataTableThemeData();
     datePickerTheme ??= const DatePickerThemeData();
-    dialogTheme ??= const DialogTheme();
+    // TODO(QuncCccccc): Clean this up once the type of `dialogTheme` is changed to `DialogThemeData`
+    if (dialogTheme != null) {
+      if (dialogTheme is DialogTheme) {
+        dialogTheme = dialogTheme.data;
+      } else if (dialogTheme is! DialogThemeData) {
+        throw ArgumentError('dialogTheme must be either a DialogThemeData or a DialogTheme');
+      }
+    }
+    dialogTheme ??= const DialogThemeData();
     dividerTheme ??= const DividerThemeData();
     drawerTheme ??= const DrawerThemeData();
     dropdownMenuTheme ??= const DropdownMenuThemeData();
@@ -590,7 +599,7 @@ class ThemeData with Diagnosticable {
       chipTheme: chipTheme,
       dataTableTheme: dataTableTheme,
       datePickerTheme: datePickerTheme,
-      dialogTheme: dialogTheme,
+      dialogTheme: dialogTheme as DialogThemeData,
       dividerTheme: dividerTheme,
       drawerTheme: drawerTheme,
       dropdownMenuTheme: dropdownMenuTheme,
@@ -1276,7 +1285,7 @@ class ThemeData with Diagnosticable {
   final DatePickerThemeData datePickerTheme;
 
   /// A theme for customizing the shape of a dialog.
-  final DialogTheme dialogTheme;
+  final DialogThemeData dialogTheme;
 
   /// A theme for customizing the color, thickness, and indents of [Divider]s,
   /// [VerticalDivider]s, etc.
@@ -1462,7 +1471,8 @@ class ThemeData with Diagnosticable {
     ChipThemeData? chipTheme,
     DataTableThemeData? dataTableTheme,
     DatePickerThemeData? datePickerTheme,
-    DialogTheme? dialogTheme,
+    // TODO(QuncCccccc): Change the parameter type to DialogThemeData
+    Object? dialogTheme,
     DividerThemeData? dividerTheme,
     DrawerThemeData? drawerTheme,
     DropdownMenuThemeData? dropdownMenuTheme,
@@ -1510,6 +1520,15 @@ class ThemeData with Diagnosticable {
     ButtonBarThemeData? buttonBarTheme,
   }) {
     cupertinoOverrideTheme = cupertinoOverrideTheme?.noDefault();
+
+    // TODO(QuncCccccc): Clean this up once the type of `dialogTheme` is changed to `DialogThemeData`
+    if (dialogTheme != null) {
+      if (dialogTheme is DialogTheme) {
+        dialogTheme = dialogTheme.data;
+      } else if (dialogTheme is! DialogThemeData) {
+        throw ArgumentError('dialogTheme must be either a DialogThemeData or a DialogTheme');
+      }
+    }
     return ThemeData.raw(
       // For the sanity of the reader, make sure these properties are in the same
       // order in every place that they are separated by section comments (e.g.
@@ -1571,7 +1590,7 @@ class ThemeData with Diagnosticable {
       chipTheme: chipTheme ?? this.chipTheme,
       dataTableTheme: dataTableTheme ?? this.dataTableTheme,
       datePickerTheme: datePickerTheme ?? this.datePickerTheme,
-      dialogTheme: dialogTheme ?? this.dialogTheme,
+      dialogTheme: dialogTheme as DialogThemeData? ?? this.dialogTheme,
       dividerTheme: dividerTheme ?? this.dividerTheme,
       drawerTheme: drawerTheme ?? this.drawerTheme,
       dropdownMenuTheme: dropdownMenuTheme ?? this.dropdownMenuTheme,
@@ -1764,7 +1783,7 @@ class ThemeData with Diagnosticable {
       chipTheme: ChipThemeData.lerp(a.chipTheme, b.chipTheme, t)!,
       dataTableTheme: DataTableThemeData.lerp(a.dataTableTheme, b.dataTableTheme, t),
       datePickerTheme: DatePickerThemeData.lerp(a.datePickerTheme, b.datePickerTheme, t),
-      dialogTheme: DialogTheme.lerp(a.dialogTheme, b.dialogTheme, t),
+      dialogTheme: DialogThemeData.lerp(a.dialogTheme, b.dialogTheme, t),
       dividerTheme: DividerThemeData.lerp(a.dividerTheme, b.dividerTheme, t),
       drawerTheme: DrawerThemeData.lerp(a.drawerTheme, b.drawerTheme, t)!,
       dropdownMenuTheme: DropdownMenuThemeData.lerp(a.dropdownMenuTheme, b.dropdownMenuTheme, t),
@@ -2062,7 +2081,7 @@ class ThemeData with Diagnosticable {
     properties.add(DiagnosticsProperty<ChipThemeData>('chipTheme', chipTheme, level: DiagnosticLevel.debug));
     properties.add(DiagnosticsProperty<DataTableThemeData>('dataTableTheme', dataTableTheme, defaultValue: defaultData.dataTableTheme, level: DiagnosticLevel.debug));
     properties.add(DiagnosticsProperty<DatePickerThemeData>('datePickerTheme', datePickerTheme, defaultValue: defaultData.datePickerTheme, level: DiagnosticLevel.debug));
-    properties.add(DiagnosticsProperty<DialogTheme>('dialogTheme', dialogTheme, defaultValue: defaultData.dialogTheme, level: DiagnosticLevel.debug));
+    properties.add(DiagnosticsProperty<DialogThemeData>('dialogTheme', dialogTheme, defaultValue: defaultData.dialogTheme, level: DiagnosticLevel.debug));
     properties.add(DiagnosticsProperty<DividerThemeData>('dividerTheme', dividerTheme, defaultValue: defaultData.dividerTheme, level: DiagnosticLevel.debug));
     properties.add(DiagnosticsProperty<DrawerThemeData>('drawerTheme', drawerTheme, defaultValue: defaultData.drawerTheme, level: DiagnosticLevel.debug));
     properties.add(DiagnosticsProperty<DropdownMenuThemeData>('dropdownMenuTheme', dropdownMenuTheme, defaultValue: defaultData.dropdownMenuTheme, level: DiagnosticLevel.debug));

packages/flutter/test/material/date_picker_test.dart

@@ -603,7 +603,7 @@ void main() {
       expect(defaultDialogMaterial.elevation, datePickerDefaultDialogTheme.elevation);
 
       // Test that it honors ThemeData.dialogTheme settings
-      const DialogTheme customDialogTheme = DialogTheme(
+      const DialogThemeData customDialogTheme = DialogThemeData(
         shape: RoundedRectangleBorder(
           borderRadius: BorderRadius.all(Radius.circular(40.0)),
         ),

packages/flutter/test/material/dialog_theme_test.dart

@@ -244,13 +244,118 @@ void main() {
     expect(padding.padding, themeActionsPadding);
   });
 
+  testWidgets('Local DialogThemeData overrides global dialogTheme', (WidgetTester tester) async {
+    const Color themeBackgroundColor = Color(0xff123456);
+    const double themeElevation = 8.0;
+    const Color themeShadowColor = Color(0xff000001);
+    const Color themeSurfaceTintColor = Color(0xff000002);
+    const BeveledRectangleBorder themeShape = BeveledRectangleBorder(borderRadius: BorderRadius.all(Radius.circular(20.5)));
+    const AlignmentGeometry themeAlignment = Alignment.bottomLeft;
+    const Color themeIconColor = Color(0xff654321);
+    const TextStyle themeTitleTextStyle = TextStyle(color: Color(0xffffffff));
+    const TextStyle themeContentTextStyle = TextStyle(color: Color(0xff000000));
+    const EdgeInsetsGeometry themeActionsPadding = EdgeInsets.all(8.0);
+    const Color themeBarrierColor = Color(0xff000005);
+    const EdgeInsets themeInsetPadding = EdgeInsets.all(30.0);
+    const Clip themeClipBehavior = Clip.antiAlias;
+
+    const Color globalBackgroundColor = Color(0xff654321);
+    const double globalElevation = 7.0;
+    const Color globalShadowColor = Color(0xff200001);
+    const Color globalSurfaceTintColor = Color(0xff222002);
+    const BeveledRectangleBorder globalShape = BeveledRectangleBorder(borderRadius: BorderRadius.all(Radius.circular(25.5)));
+    const AlignmentGeometry globalAlignment = Alignment.centerRight;
+    const Color globalIconColor = Color(0xff666666);
+    const TextStyle globalTitleTextStyle = TextStyle(color: Color(0xff000000));
+    const TextStyle globalContentTextStyle = TextStyle(color: Color(0xffdddddd));
+    const EdgeInsetsGeometry globalActionsPadding = EdgeInsets.all(18.0);
+    const Color globalBarrierColor = Color(0xff111115);
+    const EdgeInsets globalInsetPadding = EdgeInsets.all(35.0);
+    const Clip globalClipBehavior = Clip.hardEdge;
+    const AlertDialog dialog = AlertDialog(
+      title: Text('Title'),
+      content: Text('Content'),
+      icon: Icon(Icons.search),
+      actions: <Widget>[
+        Icon(Icons.cancel)
+      ],
+    );
+
+    const DialogThemeData dialogTheme = DialogThemeData(
+      backgroundColor: themeBackgroundColor,
+      elevation: themeElevation,
+      shadowColor: themeShadowColor,
+      surfaceTintColor: themeSurfaceTintColor,
+      shape: themeShape,
+      alignment: themeAlignment,
+      iconColor: themeIconColor,
+      titleTextStyle: themeTitleTextStyle,
+      contentTextStyle: themeContentTextStyle,
+      actionsPadding: themeActionsPadding,
+      barrierColor: themeBarrierColor,
+      insetPadding: themeInsetPadding,
+      clipBehavior: themeClipBehavior,
+    );
+
+    const DialogThemeData globalDialogTheme = DialogThemeData(
+      backgroundColor: globalBackgroundColor,
+      elevation: globalElevation,
+      shadowColor: globalShadowColor,
+      surfaceTintColor: globalSurfaceTintColor,
+      shape: globalShape,
+      alignment: globalAlignment,
+      iconColor: globalIconColor,
+      titleTextStyle: globalTitleTextStyle,
+      contentTextStyle: globalContentTextStyle,
+      actionsPadding: globalActionsPadding,
+      barrierColor: globalBarrierColor,
+      insetPadding: globalInsetPadding,
+      clipBehavior: globalClipBehavior,
+    );
+
+    await tester.pumpWidget(_appWithDialog(
+      tester,
+      dialog,
+      dialogTheme: dialogTheme,
+      theme: ThemeData(dialogTheme: globalDialogTheme),
+    ));
+    await tester.tap(find.text('X'));
+    await tester.pumpAndSettle();
+
+    final Material materialWidget = _getMaterialAlertDialog(tester);
+    expect(materialWidget.color, themeBackgroundColor);
+    expect(materialWidget.elevation, themeElevation);
+    expect(materialWidget.shadowColor, themeShadowColor);
+    expect(materialWidget.surfaceTintColor, themeSurfaceTintColor);
+    expect(materialWidget.shape, themeShape);
+    expect(materialWidget.clipBehavior, Clip.antiAlias);
+    final Offset bottomLeft = tester.getBottomLeft(find.descendant(
+      of: find.byType(Dialog),
+      matching: find.byType(Material)
+    ));
+    expect(bottomLeft.dx, 30.0); // 30 is the padding value.
+    expect(bottomLeft.dy, 570.0); // 600 - 30
+    expect(_getIconRenderObject(tester, Icons.search).text.style?.color, themeIconColor);
+    expect(_getTextRenderObject(tester, 'Title').text.style?.color, themeTitleTextStyle.color);
+    expect(_getTextRenderObject(tester, 'Content').text.style?.color, themeContentTextStyle.color);
+    final ModalBarrier modalBarrier = tester.widget(find.byType(ModalBarrier).last);
+    expect(modalBarrier.color, themeBarrierColor);
+
+    final Finder findPadding = find.ancestor(
+      of: find.byIcon(Icons.cancel),
+      matching: find.byType(Padding)
+    ).first;
+    final Padding padding = tester.widget<Padding>(findPadding);
+    expect(padding.padding, themeActionsPadding);
+  });
+
   testWidgets('Dialog background color', (WidgetTester tester) async {
     const Color customColor = Colors.pink;
     const AlertDialog dialog = AlertDialog(
       title: Text('Title'),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(backgroundColor: customColor));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(backgroundColor: customColor));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -269,7 +374,7 @@ void main() {
       actions: <Widget>[ ],
     );
     final ThemeData theme = ThemeData(
-      dialogTheme: const DialogTheme(
+      dialogTheme: const DialogThemeData(
         elevation: customElevation,
         shadowColor: shadowColor,
         surfaceTintColor: surfaceTintColor,
@@ -295,7 +400,7 @@ void main() {
       title: Text('Title'),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(shape: customBorder));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(shape: customBorder));
 
     await tester.pumpWidget(
       _appWithDialog(tester, dialog, theme: theme),
@@ -312,7 +417,7 @@ void main() {
       title: Text('Title'),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(alignment: Alignment.bottomLeft));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(alignment: Alignment.bottomLeft));
 
     await tester.pumpWidget(
       _appWithDialog(tester, dialog, theme: theme),
@@ -335,7 +440,7 @@ void main() {
     );
     final ThemeData theme = ThemeData(
       useMaterial3: true,
-      dialogTheme: const DialogTheme(alignment: Alignment.bottomLeft),
+      dialogTheme: const DialogThemeData(alignment: Alignment.bottomLeft),
     );
 
     await tester.pumpWidget(
@@ -359,7 +464,7 @@ void main() {
       actions: <Widget>[ ],
       alignment: Alignment.topRight,
     );
-    final ThemeData theme = ThemeData(useMaterial3: false, dialogTheme: const DialogTheme(alignment: Alignment.bottomLeft));
+    final ThemeData theme = ThemeData(useMaterial3: false, dialogTheme: const DialogThemeData(alignment: Alignment.bottomLeft));
 
     await tester.pumpWidget(
       _appWithDialog(tester, dialog, theme: theme),
@@ -383,7 +488,7 @@ void main() {
     );
     final ThemeData theme = ThemeData(
       useMaterial3: true,
-      dialogTheme: const DialogTheme(shape: customBorder),
+      dialogTheme: const DialogThemeData(shape: customBorder),
     );
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
@@ -403,7 +508,7 @@ void main() {
       title: Text('Title'),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(useMaterial3: false, dialogTheme: const DialogTheme(shape: customBorder));
+    final ThemeData theme = ThemeData(useMaterial3: false, dialogTheme: const DialogThemeData(shape: customBorder));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -419,7 +524,7 @@ void main() {
     const Color iconColor = Colors.pink, dialogThemeColor = Colors.green, iconThemeColor = Colors.yellow;
     final ThemeData theme = ThemeData(
       iconTheme: const IconThemeData(color: iconThemeColor),
-      dialogTheme: const DialogTheme(iconColor: dialogThemeColor),
+      dialogTheme: const DialogThemeData(iconColor: dialogThemeColor),
     );
     const AlertDialog dialog = AlertDialog(
       icon: Icon(Icons.ac_unit),
@@ -440,7 +545,7 @@ void main() {
     const Color dialogThemeColor = Colors.green, iconThemeColor = Colors.yellow;
     final ThemeData theme = ThemeData(
       iconTheme: const IconThemeData(color: iconThemeColor),
-      dialogTheme: const DialogTheme(iconColor: dialogThemeColor),
+      dialogTheme: const DialogThemeData(iconColor: dialogThemeColor),
     );
     const AlertDialog dialog = AlertDialog(
       icon: Icon(Icons.ac_unit),
@@ -513,7 +618,7 @@ void main() {
       title: Text(titleText),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(titleTextStyle: titleTextStyle));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(titleTextStyle: titleTextStyle));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -573,7 +678,7 @@ void main() {
     const SimpleDialog dialog = SimpleDialog(
       title: Text(titleText),
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(titleTextStyle: titleTextStyle));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(titleTextStyle: titleTextStyle));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -623,7 +728,7 @@ void main() {
       content: Text(contentText),
       actions: <Widget>[ ],
     );
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(contentTextStyle: contentTextStyle));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(contentTextStyle: contentTextStyle));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -664,7 +769,7 @@ void main() {
   testWidgets('Custom barrierColor - Theme', (WidgetTester tester) async {
     const Color barrierColor = Colors.blue;
     const SimpleDialog dialog = SimpleDialog();
-    final ThemeData theme = ThemeData(dialogTheme: const DialogTheme(barrierColor: barrierColor));
+    final ThemeData theme = ThemeData(dialogTheme: const DialogThemeData(barrierColor: barrierColor));
 
     await tester.pumpWidget(_appWithDialog(tester, dialog, theme: theme));
     await tester.tap(find.text('X'));
@@ -677,7 +782,7 @@ void main() {
   testWidgets('DialogTheme.insetPadding updates Dialog insetPadding', (WidgetTester tester) async {
     // The default testing screen (800, 600)
     const Rect screenRect = Rect.fromLTRB(0.0, 0.0, 800.0, 600.0);
-    const DialogTheme dialogTheme = DialogTheme(
+    const DialogThemeData dialogTheme = DialogThemeData(
       insetPadding: EdgeInsets.fromLTRB(10, 15, 20, 25)
     );
     const Dialog dialog = Dialog(child: Placeholder());
@@ -702,7 +807,7 @@ void main() {
   });
 
   testWidgets('DialogTheme.clipBehavior updates the dialogs clip behavior', (WidgetTester tester) async {
-    const DialogTheme dialogTheme = DialogTheme(clipBehavior: Clip.hardEdge);
+    const DialogThemeData dialogTheme = DialogThemeData(clipBehavior: Clip.hardEdge);
     const Dialog dialog = Dialog(child: Placeholder());
 
     await tester.pumpWidget(_appWithDialog(
@@ -723,7 +828,7 @@ void main() {
       child: Placeholder(),
     );
     final ThemeData theme = ThemeData(
-      dialogTheme: const DialogTheme(clipBehavior: Clip.hardEdge),
+      dialogTheme: const DialogThemeData(clipBehavior: Clip.hardEdge),
     );
 
     await tester.pumpWidget(
@@ -743,7 +848,7 @@ void main() {
     );
     final ThemeData theme = ThemeData(
       useMaterial3: false,
-      dialogTheme: const DialogTheme(clipBehavior: Clip.hardEdge),
+      dialogTheme: const DialogThemeData(clipBehavior: Clip.hardEdge),
     );
 
     await tester.pumpWidget(

packages/flutter/test/material/theme_data_test.dart

@@ -893,7 +893,7 @@ void main() {
       chipTheme: chipTheme,
       dataTableTheme: const DataTableThemeData(),
       datePickerTheme: const DatePickerThemeData(),
-      dialogTheme: const DialogTheme(backgroundColor: Colors.black),
+      dialogTheme: const DialogThemeData(backgroundColor: Colors.black),
       dividerTheme: const DividerThemeData(color: Colors.black),
       drawerTheme: const DrawerThemeData(),
       dropdownMenuTheme: const DropdownMenuThemeData(),
@@ -1007,7 +1007,7 @@ void main() {
       chipTheme: otherChipTheme,
       dataTableTheme: const DataTableThemeData(),
       datePickerTheme: const DatePickerThemeData(backgroundColor: Colors.amber),
-      dialogTheme: const DialogTheme(backgroundColor: Colors.white),
+      dialogTheme: const DialogThemeData(backgroundColor: Colors.white),
       dividerTheme: const DividerThemeData(color: Colors.white),
       drawerTheme: const DrawerThemeData(),
       dropdownMenuTheme: const DropdownMenuThemeData(),