Add:创建 flutter go web 版

packages/flutter_web/test/widgets/scrollable_fling_test.dart

@@ -0,0 +1,132 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_web_test/flutter_web_test.dart';
+import 'package:flutter_web/material.dart';
+
+const TextStyle testFont = const TextStyle(
+  color: const Color(0xFF00FF00),
+  fontFamily: 'Ahem',
+);
+
+Future<void> pumpTest(WidgetTester tester, TargetPlatform platform) async {
+  await tester.pumpWidget(new Container());
+  await tester.pumpWidget(new MaterialApp(
+    theme: new ThemeData(
+      platform: platform,
+    ),
+    home: new Container(
+      color: const Color(0xFF111111),
+      child: new ListView.builder(
+        itemBuilder: (BuildContext context, int index) {
+          return new Text('$index', style: testFont);
+        },
+      ),
+    ),
+  ));
+  return null;
+}
+
+const double dragOffset = 213.82;
+
+void main() {
+  testWidgets('Flings on different platforms', (WidgetTester tester) async {
+    double getCurrentOffset() {
+      return tester
+          .state<ScrollableState>(find.byType(Scrollable))
+          .position
+          .pixels;
+    }
+
+    await pumpTest(tester, TargetPlatform.android);
+    await tester.fling(
+        find.byType(ListView), const Offset(0.0, -dragOffset), 1000.0);
+    expect(getCurrentOffset(), dragOffset);
+    await tester.pump(); // trigger fling
+    expect(getCurrentOffset(), dragOffset);
+    await tester.pump(const Duration(seconds: 5));
+    final double result1 = getCurrentOffset();
+
+    await pumpTest(tester, TargetPlatform.iOS);
+    await tester.fling(
+        find.byType(ListView), const Offset(0.0, -dragOffset), 1000.0);
+    // Scroll starts ease into the scroll on iOS.
+    expect(getCurrentOffset(), moreOrLessEquals(210.71026666666666));
+    await tester.pump(); // trigger fling
+    expect(getCurrentOffset(), moreOrLessEquals(210.71026666666666));
+    await tester.pump(const Duration(seconds: 5));
+    final double result2 = getCurrentOffset();
+
+    expect(
+        result1,
+        lessThan(
+            result2)); // iOS (result2) is slipperier than Android (result1)
+  });
+
+  testWidgets('fling and tap to stop', (WidgetTester tester) async {
+    final List<String> log = <String>[];
+
+    final List<Widget> textWidgets = <Widget>[];
+    for (int i = 0; i < 250; i += 1)
+      textWidgets.add(new GestureDetector(
+          onTap: () {
+            log.add('tap $i');
+          },
+          child: new Text('$i', style: testFont)));
+    await tester.pumpWidget(
+      new Directionality(
+          textDirection: TextDirection.ltr,
+          child: new ListView(children: textWidgets)),
+    );
+
+    expect(log, equals(<String>[]));
+    await tester.tap(find.byType(Scrollable));
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21']));
+    await tester.fling(
+        find.byType(Scrollable), const Offset(0.0, -200.0), 1000.0);
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21']));
+    await tester.tap(
+        find.byType(Scrollable)); // should stop the fling but not tap anything
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21']));
+    await tester.tap(find.byType(Scrollable));
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21', 'tap 35']));
+  });
+
+  testWidgets('fling and wait and tap', (WidgetTester tester) async {
+    final List<String> log = <String>[];
+
+    final List<Widget> textWidgets = <Widget>[];
+    for (int i = 0; i < 250; i += 1)
+      textWidgets.add(new GestureDetector(
+          onTap: () {
+            log.add('tap $i');
+          },
+          child: new Text('$i', style: testFont)));
+    await tester.pumpWidget(
+      new Directionality(
+          textDirection: TextDirection.ltr,
+          child: new ListView(children: textWidgets)),
+    );
+
+    expect(log, equals(<String>[]));
+    await tester.tap(find.byType(Scrollable));
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21']));
+    await tester.fling(
+        find.byType(Scrollable), const Offset(0.0, -200.0), 1000.0);
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21']));
+    await tester.pump(const Duration(
+        seconds:
+            50)); // long wait, so the fling will have ended at the end of it
+    expect(log, equals(<String>['tap 21']));
+    await tester.tap(find.byType(Scrollable));
+    await tester.pump(const Duration(milliseconds: 50));
+    expect(log, equals(<String>['tap 21', 'tap 48']));
+  });
+}