Remove unneeded types (#949)

add_to_app/books/flutter_module_books/lib/api.dart

@@ -18,7 +18,7 @@ class Book {
   Thumbnail? thumbnail;
 
   Object encode() {
-    final Map<Object?, Object?> pigeonMap = <Object?, Object?>{};
+    final pigeonMap = <Object?, Object?>{};
     pigeonMap['title'] = title;
     pigeonMap['subtitle'] = subtitle;
     pigeonMap['author'] = author;
@@ -30,7 +30,7 @@ class Book {
   }
 
   static Book decode(Object message) {
-    final Map<Object?, Object?> pigeonMap = message as Map<Object?, Object?>;
+    final pigeonMap = message as Map<Object?, Object?>;
     return Book()
       ..title = pigeonMap['title'] as String?
       ..subtitle = pigeonMap['subtitle'] as String?
@@ -48,13 +48,13 @@ class Thumbnail {
   String? url;
 
   Object encode() {
-    final Map<Object?, Object?> pigeonMap = <Object?, Object?>{};
+    final pigeonMap = <Object?, Object?>{};
     pigeonMap['url'] = url;
     return pigeonMap;
   }
 
   static Thumbnail decode(Object message) {
-    final Map<Object?, Object?> pigeonMap = message as Map<Object?, Object?>;
+    final pigeonMap = message as Map<Object?, Object?>;
     return Thumbnail()..url = pigeonMap['url'] as String?;
   }
 }
@@ -89,7 +89,7 @@ abstract class FlutterBookApi {
   void displayBookDetails(Book book);
   static void setup(FlutterBookApi? api) {
     {
-      const BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
+      const channel = BasicMessageChannel<Object?>(
           'dev.flutter.pigeon.FlutterBookApi.displayBookDetails', codec);
       if (api == null) {
         channel.setMessageHandler(null);
@@ -146,7 +146,7 @@ class HostBookApi {
   static const MessageCodec<Object?> codec = _HostBookApiCodec();
 
   Future<void> cancel() async {
-    final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
+    final channel = BasicMessageChannel<Object?>(
         'dev.flutter.pigeon.HostBookApi.cancel', codec,
         binaryMessenger: _binaryMessenger);
     final Map<Object?, Object?>? replyMap =
@@ -158,8 +158,7 @@ class HostBookApi {
         details: null,
       );
     } else if (replyMap['error'] != null) {
-      final Map<Object?, Object?> error =
+      final error = (replyMap['error'] as Map<Object?, Object?>?)!;
-          (replyMap['error'] as Map<Object?, Object?>?)!;
       throw PlatformException(
         code: (error['code'] as String?)!,
         message: error['message'] as String?,

add_to_app/multiple_flutters/multiple_flutters_module/lib/main.dart

@@ -73,7 +73,7 @@ class _MyHomePageState extends State<MyHomePage> {
       body: Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
+          children: [
             const Text(
               'You have pushed the button this many times:',
             ),

android_splash_screen/lib/main.dart

@@ -59,7 +59,7 @@ class _MyHomePageState extends State<MyHomePage> {
     return Scaffold(
       body: Center(
         child: Column(
-          children: <Widget>[
+          children: [
             const Padding(
                 padding: EdgeInsets.only(top: 42, bottom: 250),
                 child: Align(

animations/lib/src/basics/08_fade_transition.dart

@@ -53,7 +53,7 @@ class _FadeTransitionDemoState extends State<FadeTransitionDemo>
       body: Center(
         child: Column(
           mainAxisSize: MainAxisSize.min,
-          children: <Widget>[
+          children: [
             FadeTransition(
               opacity: _animation,
               child: const Icon(

animations/lib/src/misc/animated_list.dart

@@ -78,7 +78,7 @@ class _AnimatedListDemoState extends State<AnimatedListDemo> {
     return Scaffold(
       appBar: AppBar(
         title: const Text('AnimatedList'),
-        actions: <Widget>[
+        actions: [
           IconButton(
             icon: const Icon(Icons.add),
             onPressed: addUser,

animations/lib/src/misc/card_swipe.dart

@@ -42,11 +42,11 @@ class _CardSwipeDemoState extends State<CardSwipeDemo> {
         padding: const EdgeInsets.all(12.0),
         child: Center(
           child: Column(
-            children: <Widget>[
+            children: [
               Expanded(
                 child: ClipRect(
                   child: Stack(
-                    children: <Widget>[
+                    children: [
                       for (final fileName in fileNames)
                         SwipeableCard(
                           imageAssetName: fileName,

experimental/desktop_photo_search/lib/main.dart

@@ -115,7 +115,7 @@ class UnsplashHomePage extends StatelessWidget {
                         onPhotoSave: (photo) async {
                           final path = await getSavePath(
                             suggestedName: '${photo.id}.jpg',
-                            acceptedTypeGroups: <XTypeGroup>[
+                            acceptedTypeGroups: [
                               XTypeGroup(
                                 label: 'JPG',
                                 extensions: ['jpg'],

experimental/desktop_photo_search/lib/src/widgets/about_dialog.dart

@@ -42,7 +42,7 @@ class PolicyDialog extends StatelessWidget {
                   text: TextSpan(
                     text: '• ',
                     style: const TextStyle(color: Colors.black, fontSize: 18),
-                    children: <TextSpan>[
+                    children: [
                       TextSpan(
                         text: 'https://policies.google.com/terms',
                         style: const TextStyle(
@@ -64,7 +64,7 @@ class PolicyDialog extends StatelessWidget {
                   text: TextSpan(
                     text: '• ',
                     style: const TextStyle(color: Colors.black, fontSize: 18),
-                    children: <TextSpan>[
+                    children: [
                       TextSpan(
                         text: 'https://unsplash.com/terms',
                         style: const TextStyle(
@@ -86,7 +86,7 @@ class PolicyDialog extends StatelessWidget {
           );
         },
       ),
-      actions: <Widget>[
+      actions: [
         TextButton(
           onPressed: () {
             Navigator.of(context).pop();

experimental/desktop_photo_search/lib/src/widgets/photo_search_dialog.dart

@@ -49,7 +49,7 @@ class _PhotoSearchDialogState extends State<PhotoSearchDialog> {
             }
           },
         ),
-        actions: <Widget>[
+        actions: [
           TextButton(
             onPressed: () {
               Navigator.of(context).pop();

experimental/web_dashboard/lib/src/widgets/dialogs.dart

@@ -17,7 +17,7 @@ class NewCategoryDialog extends StatelessWidget {
   Widget build(BuildContext context) {
     return const SimpleDialog(
       title: Text('New Category'),
-      children: <Widget>[
+      children: [
         NewCategoryForm(),
       ],
     );

experimental/web_dashboard/lib/src/widgets/edit_entry.dart

@@ -27,7 +27,7 @@ class _NewEntryFormState extends State<NewEntryForm> {
 
     return Column(
       crossAxisAlignment: CrossAxisAlignment.start,
-      children: <Widget>[
+      children: [
         Padding(
           padding: const EdgeInsets.all(8.0),
           child: CategoryDropdown(

form_app/lib/src/autofill.dart

@@ -65,7 +65,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                         hintText: '(123) 456-7890',
                         labelText: 'Telephone',
                       ),
-                      autofillHints: <String>[AutofillHints.telephoneNumber],
+                      autofillHints: [AutofillHints.telephoneNumber],
                     ),
                     const TextField(
                       keyboardType: TextInputType.streetAddress,
@@ -74,7 +74,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                         hintText: '123 4th Ave',
                         labelText: 'Street Address',
                       ),
-                      autofillHints: <String>[AutofillHints.streetAddressLine1],
+                      autofillHints: [AutofillHints.streetAddressLine1],
                     ),
                     const TextField(
                       keyboardType: TextInputType.number,
@@ -83,7 +83,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                         hintText: '12345',
                         labelText: 'Postal Code',
                       ),
-                      autofillHints: <String>[AutofillHints.postalCode],
+                      autofillHints: [AutofillHints.postalCode],
                     ),
                     const TextField(
                       textInputAction: TextInputAction.next,
@@ -91,7 +91,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                         hintText: 'United States',
                         labelText: 'Country',
                       ),
-                      autofillHints: <String>[AutofillHints.countryName],
+                      autofillHints: [AutofillHints.countryName],
                     ),
                     const TextField(
                       keyboardType: TextInputType.number,
@@ -99,7 +99,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                         hintText: '1',
                         labelText: 'Country Code',
                       ),
-                      autofillHints: <String>[AutofillHints.countryCode],
+                      autofillHints: [AutofillHints.countryCode],
                     ),
                   ].expand(
                     (widget) => [

ios_app_clip/lib/main.dart

@@ -43,7 +43,7 @@ class _DemoState extends State<Demo> {
         child: Center(
           child: Column(
             mainAxisAlignment: MainAxisAlignment.center,
-            children: <Widget>[
+            children: [
               Text(deviceInfo),
               const Padding(padding: EdgeInsets.only(top: 18)),
               const FlutterLogo(size: 128),

jsonexample/test/simple_object_unit_test.dart

@@ -11,7 +11,7 @@ import 'package:jsonexample/dart_convert/converted_simple_object.dart';
 import 'package:jsonexample/json_serializable/serializable_simple_object.dart';
 
 void main() {
-  const typicalObjectJson = <String, dynamic>{
+  const typicalObjectJson = {
     'aString': 'Blah, blah, blah.',
     'anInt': 1,
     'aDouble': 1.0,
@@ -20,7 +20,7 @@ void main() {
     'aListOfDoubles': [1.0, 2.0, 3.0]
   };
 
-  const emptyListJson = <String, dynamic>{
+  const emptyListJson = {
     'aString': 'Blah, blah, blah.',
     'anInt': 1,
     'aDouble': 1.0,
@@ -29,7 +29,7 @@ void main() {
     'aListOfDoubles': <double>[]
   };
 
-  const unexpectedPropertiesJson = <String, dynamic>{
+  const unexpectedPropertiesJson = {
     'aString': 'Blah, blah, blah.',
     'anInt': 1,
     'aDouble': 1.0,

place_tracker/lib/stub_data.dart

@@ -145,7 +145,7 @@ class StubData {
     ),
   ];
 
-  static const reviewStrings = <String>[
+  static const reviewStrings = [
     'My favorite place in Portland. The employees are wonderful and so is the food. I go here at least once a month!',
     'Staff was very friendly. Great atmosphere and good music. Would recommend.',
     'Best. Place. In. Town. Period.'

platform_channels/lib/src/add_pet_details.dart

@@ -25,7 +25,7 @@ class _AddPetDetailsState extends State<AddPetDetails> {
     return Scaffold(
       appBar: AppBar(
         title: const Text('Add Pet Details'),
-        actions: <Widget>[
+        actions: [
           IconButton(
             icon: const Icon(Icons.add),
             onPressed: () {

provider_counter/lib/main.dart

@@ -63,7 +63,7 @@ class MyHomePage extends StatelessWidget {
       body: Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
+          children: [
             const Text('You have pushed the button this many times:'),
             // Consumer looks for an ancestor Provider widget
             // and retrieves its model (Counter, in this case).

testing_app/lib/screens/home.dart

@@ -17,7 +17,7 @@ class HomePage extends StatelessWidget {
     return Scaffold(
       appBar: AppBar(
         title: const Text('Testing Sample'),
-        actions: <Widget>[
+        actions: [
           TextButton.icon(
             style: TextButton.styleFrom(primary: Colors.white),
             onPressed: () {

veggieseasons/lib/screens/details.dart

@@ -174,7 +174,7 @@ class InfoView extends StatelessWidget {
         children: [
           Row(
             mainAxisSize: MainAxisSize.max,
-            children: <Widget>[
+            children: [
               FutureBuilder<Set<VeggieCategory>>(
                 future: prefs.preferredCategories,
                 builder: (context, snapshot) {

veggieseasons/lib/screens/settings.dart

@@ -233,7 +233,7 @@ class SettingsScreen extends StatelessWidget {
             content: const Text(
               'Are you sure you want to reset the current settings?',
             ),
-            actions: <Widget>[
+            actions: [
               CupertinoDialogAction(
                 isDestructiveAction: true,
                 child: const Text('Yes'),
@@ -266,7 +266,7 @@ class SettingsScreen extends StatelessWidget {
               Styles.scaffoldBackground(CupertinoTheme.brightnessOf(context)),
           child: CustomScrollView(
             restorationId: 'list',
-            slivers: <Widget>[
+            slivers: [
               const CupertinoSliverNavigationBar(
                 largeTitle: Text('Settings'),
               ),
@@ -274,7 +274,7 @@ class SettingsScreen extends StatelessWidget {
                 top: false,
                 sliver: SliverList(
                   delegate: SliverChildListDelegate(
-                    <Widget>[
+                    [
                       SettingsGroup(
                         items: [
                           _buildCaloriesItem(context, prefs),

veggieseasons/lib/widgets/settings_item.dart

@@ -130,7 +130,7 @@ class SettingsItemState extends State<SettingsItem> {
                   child: widget.subtitle != null
                       ? Column(
                           crossAxisAlignment: CrossAxisAlignment.start,
-                          children: <Widget>[
+                          children: [
                             const SizedBox(height: 8.5),
                             Text(widget.label,
                                 style: themeData.textTheme.textStyle),

veggieseasons/lib/widgets/veggie_card.dart

@@ -122,7 +122,7 @@ class VeggieCard extends StatelessWidget {
         padding: const EdgeInsets.all(16),
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
-          children: <Widget>[
+          children: [
             Text(
               veggie.name,
               style: Styles.cardTitleText(themeData),

web/charts/lib/axes/line_disjoint_axis.dart

@@ -153,7 +153,7 @@ class DisjointMeasureAxisLineChart extends StatelessWidget {
         primaryMeasureAxis: const charts.NumericAxisSpec(
             tickProviderSpec: charts.StaticNumericTickProviderSpec(
           // Create the ticks to be used the domain axis.
-          <charts.TickSpec<num>>[
+          [
             charts.TickSpec(0, label: ''),
             charts.TickSpec(1, label: ''),
             charts.TickSpec(2, label: ''),

web/charts/lib/axes/statically_provided_ticks.dart

@@ -81,7 +81,7 @@ class StaticallyProvidedTicks extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     // Create the ticks to be used the domain axis.
-    final staticTicks = <charts.TickSpec<String>>[
+    final staticTicks = [
       const charts.TickSpec(
           // Value must match the domain value.
           '2014',

web/charts/lib/drawer.dart

@@ -29,7 +29,7 @@ class GalleryDrawer extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return Drawer(
-      child: ListView(children: <Widget>[
+      child: ListView(children: [
         // Performance overlay toggle.
         ListTile(
           leading: const Icon(Icons.assessment),

web/charts/lib/gallery_scaffold.dart

@@ -57,7 +57,7 @@ class _GalleryScaffoldState extends State<GalleryScaffold> {
       appBar: AppBar(title: Text(widget.title)),
       body: Padding(
           padding: const EdgeInsets.all(8.0),
-          child: Column(children: <Widget>[
+          child: Column(children: [
             SizedBox(height: 250.0, child: widget.childBuilder()),
           ])),
       floatingActionButton: FloatingActionButton(

web/github_dataviz/lib/catmull.dart

@@ -60,7 +60,7 @@ class CatmullInterpolator implements Interpolator {
   }
 
   static void test() {
-    List<Point2D> controlPoints = <Point2D>[];
+    final controlPoints = <Point2D>[];
     controlPoints.add(Point2D(-1, 1));
     controlPoints.add(Point2D(0, 1));
     controlPoints.add(Point2D(1, -1));

web/github_dataviz/lib/layered_chart.dart

@@ -49,9 +49,9 @@ class LayeredChartState extends State<LayeredChart> {
     graphHeight = MathUtils.clampedMap(screenRatio, 0.5, 2.5, 50, 150);
 
     int m = dataToPlot.length;
-    paths = <Path>[];
+    paths = [];
-    capPaths = <Path>[];
+    capPaths = [];
-    maxValues = <double>[];
+    maxValues = [];
     for (int i = 0; i < m; i++) {
       int n = dataToPlot[i].series.length;
       maxValues.add(0);
@@ -71,11 +71,11 @@ class LayeredChartState extends State<LayeredChart> {
     double xWidth = (endX - startX) / numPoints;
     double capRangeX = capSize * cos(capTheta);
     double tanCapTheta = tan(capTheta);
-    List<double> curvePoints = <double>[];
+    final curvePoints = <double>[];
     for (int i = 0; i < m; i++) {
       List<int> series = dataToPlot[i].series;
       int n = series.length;
-      List<Point2D> controlPoints = <Point2D>[];
+      final controlPoints = <Point2D>[];
       controlPoints.add(Point2D(-1, 0));
       double last = 0;
       for (int j = 0; j < n; j++) {
@@ -135,7 +135,7 @@ class LayeredChartState extends State<LayeredChart> {
       capPaths[i].lineTo(startX, startY + 1);
       capPaths[i].close();
     }
-    labelPainter = <TextPainter>[];
+    labelPainter = [];
     for (int i = 0; i < dataToPlot.length; i++) {
       TextSpan span = TextSpan(
           style: const TextStyle(
@@ -148,7 +148,7 @@ class LayeredChartState extends State<LayeredChart> {
       tp.layout();
       labelPainter.add(tp);
     }
-    milestonePainter = <TextPainter>[];
+    milestonePainter = [];
     for (int i = 0; i < milestones.length; i++) {
       TextSpan span = TextSpan(
           style: const TextStyle(

web/github_dataviz/lib/main.dart

@@ -48,7 +48,7 @@ class _MainLayoutState extends State<MainLayout> with TickerProviderStateMixin {
 
     createAnimation(0);
 
-    weekLabels = <WeekLabel>[];
+    weekLabels = [];
     weekLabels.add(WeekLabel.forDate(DateTime(2019, 2, 26), 'v1.2'));
     weekLabels.add(WeekLabel.forDate(DateTime(2018, 12, 4), 'v1.0'));
 //    weekLabels.add(WeekLabel.forDate(new DateTime(2018, 9, 19), "Preview 2"));
@@ -155,7 +155,7 @@ class _MainLayoutState extends State<MainLayout> with TickerProviderStateMixin {
     Column mainColumn = Column(
       mainAxisAlignment: MainAxisAlignment.center,
       mainAxisSize: MainAxisSize.max,
-      children: <Widget>[
+      children: [
         Expanded(child: layeredChart),
         Padding(
           padding: const EdgeInsets.only(

web/particle_background/lib/main.dart

@@ -20,7 +20,7 @@ class ParticleBackgroundPage extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return Stack(
-      children: <Widget>[
+      children: [
         Positioned.fill(child: AnimatedBackground()),
         Positioned.fill(child: Particles(30)),
         Positioned.fill(child: CenteredText()),