packages/flutter/test/material/persistent_bottom_sheet_test.dart

// 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_test/flutter_test.dart';
import 'package:flutter/material.dart';

void main() {
  testWidgets('Verify that a BottomSheet can be rebuilt with ScaffoldFeatureController.setState()', (WidgetTester tester) async {
    final GlobalKey<ScaffoldState> scaffoldKey = new GlobalKey<ScaffoldState>();
    PersistentBottomSheetController<Null> bottomSheet;
    int buildCount = 0;

    await tester.pumpWidget(new MaterialApp(
      home: new Scaffold(
        key: scaffoldKey,
        body: const Center(child: const Text('body'))
      )
    ));

    bottomSheet = scaffoldKey.currentState.showBottomSheet<Null>((_) {
      return new Builder(
        builder: (BuildContext context) {
          buildCount += 1;
          return new Container(height: 200.0);
        }
      );
    });

    await tester.pump();
    expect(buildCount, equals(1));

    bottomSheet.setState((){ });
    await tester.pump();
    expect(buildCount, equals(2));
  });

  testWidgets('Verify that a scrollable BottomSheet can be dismissed', (WidgetTester tester) async {
    final GlobalKey<ScaffoldState> scaffoldKey = new GlobalKey<ScaffoldState>();

    await tester.pumpWidget(new MaterialApp(
      home: new Scaffold(
        key: scaffoldKey,
        body: const Center(child: const Text('body'))
      )
    ));

    scaffoldKey.currentState.showBottomSheet<Null>((BuildContext context) {
      return new ListView(
        shrinkWrap: true,
        primary: false,
        children: <Widget>[
          new Container(height: 100.0, child: const Text('One')),
          new Container(height: 100.0, child: const Text('Two')),
          new Container(height: 100.0, child: const Text('Three')),
        ],
      );
    });

    await tester.pumpAndSettle();

    expect(find.text('Two'), findsOneWidget);

    await tester.drag(find.text('Two'), const Offset(0.0, 400.0));
    await tester.pumpAndSettle();

    expect(find.text('Two'), findsNothing);
  });

}