Revert "Remove catalog (#67470)" (#67542)

This reverts commit 2462f696.

examples/catalog/README.md

+Samples Catalog
+=======
+
+A collection of sample apps that demonstrate how Flutter can be used.
+
+Each sample app is contained in a single `.dart` file located in the `lib`
+directory. To run each sample app, specify the corresponding file on the
+`flutter run` command line, for example:
+
+```
+flutter run lib/animated_list.dart
+flutter run lib/app_bar_bottom.dart
+flutter run lib/basic_app_bar.dart
+...
+```
+
+The apps are intended to be short and easily understood. Classes that represent
+the sample's focus are at the top of the file; data and support classes follow.
+
+Each sample app contains a comment (usually at the end) which provides some
+standard documentation that also appears in the web view of the catalog.
+See the "Generating..." section below.
+
+Generating the web view of the catalog
+---------
+
+Markdown and a screenshot of each app are produced by `bin/sample_page.dart`
+and saved in the `.generated` directory. The markdown file contains
+the text taken from the Sample Catalog comment found in the app's source
+file, followed by the source code itself.
+
+This `sample_page.dart` command-line app must be run from the `examples/catalog`
+directory. It relies on templates also found in the bin directory, and it
+generates and executes `test_driver` apps to collect the screenshots:
+
+```
+cd examples/catalog
+dart bin/sample_page.dart
+```

examples/catalog/android/app/build.gradle

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+def localProperties = new Properties()
+def localPropertiesFile = rootProject.file('local.properties')
+if (localPropertiesFile.exists()) {
+    localPropertiesFile.withReader('UTF-8') { reader ->
+        localProperties.load(reader)
+    }
+}
+
+def flutterRoot = localProperties.getProperty('flutter.sdk')
+if (flutterRoot == null) {
+    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
+}
+
+def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
+if (flutterVersionCode == null) {
+    flutterVersionCode = '1'
+}
+
+def flutterVersionName = localProperties.getProperty('flutter.versionName')
+if (flutterVersionName == null) {
+    flutterVersionName = '1.0'
+}
+
+apply plugin: 'com.android.application'
+apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+
+android {
+    compileSdkVersion 29
+
+    lintOptions {
+        disable 'InvalidPackage'
+    }
+
+    defaultConfig {
+        applicationId "io.flutter.examples.catalog"
+        minSdkVersion 16
+        targetSdkVersion 29
+        versionCode flutterVersionCode.toInteger()
+        versionName flutterVersionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig signingConfigs.debug
+        }
+    }
+}
+
+flutter {
+    source '../..'
+}

examples/catalog/android/app/src/main/AndroidManifest.xml

+<!-- Copyright 2014 The Flutter Authors. All rights reserved.
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file. -->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.yourcompany.animated_list">
+
+    <!-- The INTERNET permission is required for development. Specifically,
+         flutter needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+
+    <application android:label="animated_list" android:icon="@mipmap/ic_launcher">
+        <activity android:name="io.flutter.embedding.android.FlutterActivity"
+                  android:theme="@android:style/Theme.Black.NoTitleBar"
+                  android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+                  android:hardwareAccelerated="true"
+                  android:windowSoftInputMode="adjustResize">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+    </application>
+</manifest>

examples/catalog/android/build.gradle

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+buildscript {
+    repositories {
+        google()
+        jcenter()
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:3.5.0'
+    }
+}
+
+allprojects {
+    repositories {
+        google()
+        jcenter()
+    }
+}
+
+rootProject.buildDir = '../build'
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+}
+subprojects {
+    project.evaluationDependsOn(':app')
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}

examples/catalog/android/gradle.properties

+org.gradle.jvmargs=-Xmx1536M
+android.useAndroidX=true
+android.enableJetifier=true
+android.enableR8=true

examples/catalog/android/gradle/wrapper/gradle-wrapper.properties

+#Fri Jun 23 08:50:38 CEST 2017
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.2-all.zip

examples/catalog/android/settings.gradle

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+include ':app'
+
+def localPropertiesFile = new File(rootProject.projectDir, "local.properties")
+def properties = new Properties()
+
+assert localPropertiesFile.exists()
+localPropertiesFile.withReader("UTF-8") { reader -> properties.load(reader) }
+
+def flutterSdkPath = properties.getProperty("flutter.sdk")
+assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
+apply from: "$flutterSdkPath/packages/flutter_tools/gradle/app_plugin_loader.gradle"

examples/catalog/bin/class_index.md.template

+---
+layout: page
+title: "@(class) Sample Apps"
+permalink: /catalog/samples/@(link)/
+---
+
+All of the sample apps listed here use the Flutter @(class) class in an interesting way. The <a href="/catalog/samples/">Sample App Catalog</a> page lists all of the sample apps.
+
+<div class="container-fluid">
+@(entries)
+</div>

examples/catalog/bin/entry.md.template

+  <div class="row" style="margin-bottom: 32px">
+    <a href="/catalog/samples/@(link)/">
+      <div class="col-md-3">
+        <img style="border:1px solid #000000" src="@(android screenshot)" alt="Android screenshot" class="img-responsive">
+      </div>
+   </a>
+    <div class="col-md-9">
+      <p>
+        @(summary)
+      </p>
+      <p>
+        This app features the following classes: @(classes).
+      </p>
+      <p>
+        <a href="/catalog/samples/@(link)/">Learn more</a>.
+      </p>
+    </div>
+  </div>

examples/catalog/bin/index.md.template

+---
+layout: page
+title: "Sample App Catalog"
+permalink: /catalog/samples/
+---
+
+This catalog lists applications that demonstrate how to implement common mobile design patterns with Flutter. Each sample demonstrates how a few Flutter widgets can be put together to implement a meaningful user interface. The samples are short - just one Dart file - but they're complete applications. They should be easy to try out and tweak with your favorite IDE/code editor.
+
+If there are other sample apps that you'd like to see we'd appreciate hearing from you on our [Gitter channel](https://gitter.im/flutter/flutter) or [mailing list](https://groups.google.com/d/forum/flutter-dev).
+
+<div class="container-fluid">
+@(entries)
+</div>

examples/catalog/bin/sample_page.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This application generates markdown pages and screenshots for each
+// sample app. For more information see ../README.md.
+
+import 'dart:io';
+
+import 'package:path/path.dart';
+
+class SampleError extends Error {
+  SampleError(this.message);
+  final String message;
+  @override
+  String toString() => 'SampleError($message)';
+}
+
+// Sample apps are .dart files in the lib directory which contain a block
+// comment that begins with a '/* Sample Catalog' line, and ends with a line
+// that just contains '*/'. The following keywords may appear at the
+// beginning of lines within the comment. A keyword's value is all of
+// the following text up to the next keyword or the end of the comment,
+// sans leading and trailing whitespace.
+const String sampleCatalogKeywords = r'^Title:|^Summary:|^Description:|^Classes:|^Sample:|^See also:';
+
+Directory outputDirectory;
+Directory sampleDirectory;
+Directory testDirectory;
+Directory driverDirectory;
+
+void logMessage(String s) { print(s); }
+void logError(String s) { print(s); }
+
+File inputFile(String dir, String name) {
+  return File(dir + Platform.pathSeparator + name);
+}
+
+File outputFile(String name, [Directory directory]) {
+  return File((directory ?? outputDirectory).path + Platform.pathSeparator + name);
+}
+
+void initialize() {
+  outputDirectory = Directory('.generated');
+  sampleDirectory = Directory('lib');
+  testDirectory = Directory('test');
+  driverDirectory = Directory('test_driver');
+  outputDirectory.createSync();
+}
+
+// Return a copy of template with each occurrence of @(foo) replaced
+// by values[foo].
+String expandTemplate(String template, Map<String, String> values) {
+  // Matches @(foo), match[1] == 'foo'
+  final RegExp tokenRE = RegExp(r'@\(([\w ]+)\)', multiLine: true);
+  return template.replaceAllMapped(tokenRE, (Match match) {
+    if (match.groupCount != 1)
+      throw SampleError('bad template keyword $match[0]');
+    final String keyword = match[1];
+    return values[keyword] ?? '';
+  });
+}
+
+void writeExpandedTemplate(File output, String template, Map<String, String> values) {
+  output.writeAsStringSync(expandTemplate(template, values));
+  logMessage('wrote $output');
+}
+
+class SampleInfo {
+  SampleInfo(this.sourceFile, this.commit);
+
+  final File sourceFile;
+  final String commit;
+  String sourceCode;
+  Map<String, String> commentValues;
+
+  // If sourceFile is lib/foo.dart then sourceName is foo. The sourceName
+  // is used to create derived filenames like foo.md or foo.png.
+  String get sourceName => basenameWithoutExtension(sourceFile.path);
+
+  // The website's link to this page will be /catalog/samples/@(link)/.
+  String get link => sourceName.replaceAll('_', '-');
+
+  // The name of the widget class that defines this sample app, like 'FooSample'.
+  String get sampleClass => commentValues['sample'];
+
+  // The value of the 'Classes:' comment as a list of class names.
+  Iterable<String> get highlightedClasses {
+    final String classNames = commentValues['classes'];
+    if (classNames == null)
+      return const <String>[];
+    return classNames.split(',').map<String>((String s) => s.trim()).where((String s) => s.isNotEmpty);
+  }
+
+  // The relative import path for this sample, like '../lib/foo.dart'.
+  String get importPath => '..' + Platform.pathSeparator + sourceFile.path;
+
+  // Return true if we're able to find the "Sample Catalog" comment in the
+  // sourceFile, and we're able to load its keyword/value pairs into
+  // the commentValues Map. The rest of the file's contents are saved
+  // in sourceCode.
+  bool initialize() {
+    final String contents = sourceFile.readAsStringSync();
+
+    final RegExp startRE = RegExp(r'^/\*\s+^Sample\s+Catalog', multiLine: true);
+    final RegExp endRE = RegExp(r'^\*/', multiLine: true);
+    final Match startMatch = startRE.firstMatch(contents);
+    if (startMatch == null)
+      return false;
+
+    final int startIndex = startMatch.end;
+    final Match endMatch = endRE.firstMatch(contents.substring(startIndex));
+    if (endMatch == null)
+      return false;
+
+    final String comment = contents.substring(startIndex, startIndex + endMatch.start);
+    sourceCode = contents.substring(0, startMatch.start) + contents.substring(startIndex + endMatch.end);
+    if (sourceCode.trim().isEmpty)
+      throw SampleError('did not find any source code in $sourceFile');
+
+    final RegExp keywordsRE = RegExp(sampleCatalogKeywords, multiLine: true);
+    final List<Match> keywordMatches = keywordsRE.allMatches(comment).toList();
+    if (keywordMatches.isEmpty)
+      throw SampleError('did not find any keywords in the Sample Catalog comment in $sourceFile');
+
+    commentValues = <String, String>{};
+    for (int i = 0; i < keywordMatches.length; i += 1) {
+      final String keyword = comment.substring(keywordMatches[i].start, keywordMatches[i].end - 1);
+      final String value = comment.substring(
+        keywordMatches[i].end,
+        i == keywordMatches.length - 1 ? null : keywordMatches[i + 1].start,
+      );
+      commentValues[keyword.toLowerCase()] = value.trim();
+    }
+    commentValues['name'] = sourceName;
+    commentValues['path'] = 'examples/catalog/${sourceFile.path}';
+    commentValues['source'] = sourceCode.trim();
+    commentValues['link'] = link;
+    commentValues['android screenshot'] = 'https://storage.googleapis.com/flutter-catalog/$commit/${sourceName}_small.png';
+
+    return true;
+  }
+}
+
+void generate(String commit) {
+  initialize();
+
+  final List<SampleInfo> samples = <SampleInfo>[];
+  for (final FileSystemEntity entity in sampleDirectory.listSync()) {
+    if (entity is File && entity.path.endsWith('.dart')) {
+      final SampleInfo sample = SampleInfo(entity, commit);
+      if (sample.initialize()) // skip files that lack the Sample Catalog comment
+        samples.add(sample);
+    }
+  }
+
+  // Causes the generated imports to appear in alphabetical order.
+  // Avoid complaints from flutter lint.
+  samples.sort((SampleInfo a, SampleInfo b) {
+    return a.sourceName.compareTo(b.sourceName);
+  });
+
+  final String entryTemplate = inputFile('bin', 'entry.md.template').readAsStringSync();
+
+  // Write the sample catalog's home page: index.md
+  final Iterable<String> entries = samples.map<String>((SampleInfo sample) {
+    return expandTemplate(entryTemplate, sample.commentValues);
+  });
+  writeExpandedTemplate(
+    outputFile('index.md'),
+    inputFile('bin', 'index.md.template').readAsStringSync(),
+    <String, String>{
+      'entries': entries.join('\n'),
+    },
+  );
+
+  // Write the sample app files, like animated_list.md
+  for (final SampleInfo sample in samples) {
+    writeExpandedTemplate(
+      outputFile(sample.sourceName + '.md'),
+      inputFile('bin', 'sample_page.md.template').readAsStringSync(),
+      sample.commentValues,
+    );
+  }
+
+  // For each unique class listened in a sample app's "Classes:" list, generate
+  // a file that's structurally the same as index.md but only contains samples
+  // that feature one class. For example AnimatedList_index.md would only
+  // include samples that had AnimatedList in their "Classes:" list.
+  final Map<String, List<SampleInfo>> classToSamples = <String, List<SampleInfo>>{};
+  for (final SampleInfo sample in samples) {
+    for (final String className in sample.highlightedClasses) {
+      classToSamples[className] ??= <SampleInfo>[];
+      classToSamples[className].add(sample);
+    }
+  }
+  for (final String className in classToSamples.keys) {
+    final Iterable<String> entries = classToSamples[className].map<String>((SampleInfo sample) {
+      return expandTemplate(entryTemplate, sample.commentValues);
+    });
+    writeExpandedTemplate(
+      outputFile('${className}_index.md'),
+      inputFile('bin', 'class_index.md.template').readAsStringSync(),
+      <String, String>{
+        'class': className,
+        'entries': entries.join('\n'),
+        'link': '${className}_index',
+      },
+    );
+  }
+
+  // Write screenshot.dart, a "test" app that displays each sample
+  // app in turn when the app is tapped.
+  writeExpandedTemplate(
+    outputFile('screenshot.dart', driverDirectory),
+    inputFile('bin', 'screenshot.dart.template').readAsStringSync(),
+    <String, String>{
+      'imports': samples.map<String>((SampleInfo page) {
+        return "import '${page.importPath}' show ${page.sampleClass};\n";
+      }).join(),
+      'widgets': samples.map<String>((SampleInfo sample) {
+        return 'new ${sample.sampleClass}(),\n';
+      }).join(),
+    },
+  );
+
+  // Write screenshot_test.dart, a test driver for screenshot.dart
+  // that collects screenshots of each app and saves them.
+  writeExpandedTemplate(
+    outputFile('screenshot_test.dart', driverDirectory),
+    inputFile('bin', 'screenshot_test.dart.template').readAsStringSync(),
+    <String, String>{
+      'paths': samples.map<String>((SampleInfo sample) {
+        return "'${outputFile(sample.sourceName + '.png').path}'";
+      }).join(',\n'),
+    },
+  );
+
+  // For now, the website's index.json file must be updated by hand.
+  logMessage('The following entries must appear in _data/catalog/widgets.json');
+  for (final String className in classToSamples.keys)
+    logMessage('"sample": "${className}_index"');
+}
+
+void main(List<String> args) {
+  if (args.length != 1) {
+    logError(
+      'Usage (cd examples/catalog/; dart bin/sample_page.dart commit)\n'
+      'The flutter commit hash locates screenshots on storage.googleapis.com/flutter-catalog/'
+    );
+    exit(255);
+  }
+  try {
+    generate(args[0]);
+  } catch (error) {
+    logError(
+      'Error: sample_page.dart failed: $error\n'
+      'This sample_page.dart app expects to be run from the examples/catalog directory. '
+      'More information can be found in examples/catalog/README.md.'
+    );
+    exit(255);
+  }
+  exit(0);
+}

examples/catalog/bin/sample_page.md.template

+---
+layout: page
+title: "@(title)"
+permalink: /catalog/samples/@(link)/
+---
+
+@(summary)
+
+<p>
+  <div class="container-fluid">
+    <div class="row">
+      <div class="col-md-4">
+        <div class="panel panel-default">
+          <div class="panel-body" style="padding: 16px 32px;">
+            <img style="border:1px solid #000000" src="@(android screenshot)" alt="Android screenshot" class="img-responsive">
+          </div>
+          <div class="panel-footer">
+            Android screenshot
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+</p>
+
+@(description)
+
+Try this app out by creating a new project with `flutter create` and replacing the contents of `lib/main.dart` with the code that follows.
+
+```dart
+@(source)
+```
+
+<h2>See also:</h2>
+@(see also)
+- The source code in [@(path)](https://github.com/flutter/flutter/blob/master/@(path)).

examples/catalog/bin/screenshot.dart.template

+// This file was generated using bin/screenshot.dart.template and
+// bin/sample_page.dart. For more information see README.md.
+
+import 'package:flutter_driver/driver_extension.dart';
+import 'package:flutter/material.dart';
+
+@(imports)
+
+class SampleScreenshots extends StatefulWidget {
+  @override
+  SampleScreenshotsState createState() => new SampleScreenshotsState();
+}
+
+class SampleScreenshotsState extends State<SampleScreenshots> {
+  final List<Widget> samples = <Widget>[
+    @(widgets)
+  ];
+  int sampleIndex = 0;
+
+  @override
+  Widget build(BuildContext context) {
+    return new GestureDetector(
+      key: const ValueKey<String>('screenshotGestureDetector'),
+      behavior: HitTestBehavior.opaque,
+      onTap: () {
+        setState(() {
+          sampleIndex += 1;
+        });
+      },
+      child: new IgnorePointer(
+        child: samples[sampleIndex % samples.length],
+      ),
+    );
+  }
+}
+
+void main() {
+  enableFlutterDriverExtension();
+  WidgetsApp.debugAllowBannerOverride = false; // No "debug" banner.
+  runApp(new SampleScreenshots());
+}

examples/catalog/bin/screenshot_test.dart.template

+// This file was generated using bin/screenshot_test.dart.template and
+// bin/sample_page.dart. For more information see README.md.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:flutter_driver/flutter_driver.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('sample screenshots', () {
+    FlutterDriver driver;
+
+    setUpAll(() async {
+      driver = await FlutterDriver.connect();
+    });
+
+    tearDownAll(() async {
+      await driver?.close();
+    });
+
+    test('take sample screenshots', () async {
+      final List<String> paths = <String>[
+        @(paths)
+      ];
+      for (String path in paths) {
+        await driver.waitUntilNoTransientCallbacks();
+        final List<int> pixels = await driver.screenshot();
+        final File file = new File(path);
+        await file.writeAsBytes(pixels);
+        print('wrote $file');
+        await driver.tap(find.byValueKey('screenshotGestureDetector'));
+      }
+    });
+  });
+}

examples/catalog/ios/Flutter/AppFrameworkInfo.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+  <key>CFBundleDevelopmentRegion</key>
+  <string>$(DEVELOPMENT_LANGUAGE)</string>
+  <key>CFBundleExecutable</key>
+  <string>App</string>
+  <key>CFBundleIdentifier</key>
+  <string>io.flutter.flutter.app</string>
+  <key>CFBundleInfoDictionaryVersion</key>
+  <string>6.0</string>
+  <key>CFBundleName</key>
+  <string>App</string>
+  <key>CFBundlePackageType</key>
+  <string>FMWK</string>
+  <key>CFBundleShortVersionString</key>
+  <string>1.0</string>
+  <key>CFBundleSignature</key>
+  <string>????</string>
+  <key>CFBundleVersion</key>
+  <string>1.0</string>
+  <key>MinimumOSVersion</key>
+  <string>9.0</string>
+</dict>
+</plist>

examples/catalog/ios/Flutter/Debug.xcconfig

+#include "Generated.xcconfig"

examples/catalog/ios/Flutter/Release.xcconfig

+#include "Generated.xcconfig"

examples/catalog/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata

+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Runner.xcodeproj">
+   </FileRef>
+   <FileRef
+      location = "group:Pods/Pods.xcodeproj">
+   </FileRef>
+</Workspace>

examples/catalog/ios/Runner.xcodeproj/project.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>

examples/catalog/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1020"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+               BuildableName = "Runner.app"
+               BlueprintName = "Runner"
+               ReferencedContainer = "container:Runner.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

examples/catalog/ios/Runner.xcworkspace/contents.xcworkspacedata

+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Runner.xcodeproj">
+   </FileRef>
+</Workspace>

examples/catalog/ios/Runner/AppDelegate.h

+// Copyright 2014 The Flutter 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 <UIKit/UIKit.h>
+#import <Flutter/Flutter.h>
+
+@interface AppDelegate : FlutterAppDelegate
+
+@end

examples/catalog/ios/Runner/AppDelegate.m

+// Copyright 2014 The Flutter 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 "AppDelegate.h"
+#import "GeneratedPluginRegistrant.h"
+
+@implementation AppDelegate
+
+- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+    [GeneratedPluginRegistrant registerWithRegistry:self];
+    // Override point for customization after application launch.
+    return [super application:application didFinishLaunchingWithOptions:launchOptions];
+}
+@end

examples/catalog/ios/Runner/Assets.xcassets/AppIcon.appiconset/Contents.json

+{
+  "images" : [
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "83.5x83.5",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-83.5x83.5@2x.png",
+      "scale" : "2x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

examples/catalog/ios/Runner/Base.lproj/LaunchScreen.storyboard

+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="15F34" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" initialViewController="01J-lp-oVM">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
+    </dependencies>
+    <scenes>
+        <!--View Controller-->
+        <scene sceneID="EHf-IW-A2E">
+            <objects>
+                <viewController id="01J-lp-oVM" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="Llm-lL-Icb"/>
+                        <viewControllerLayoutGuide type="bottom" id="xb3-aO-Qok"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
+                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="53" y="375"/>
+        </scene>
+    </scenes>
+</document>

examples/catalog/ios/Runner/Base.lproj/Main.storyboard

+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="15F34" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="BYZ-38-t0r">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
+    </dependencies>
+    <scenes>
+        <!--Flutter View Controller-->
+        <scene sceneID="tne-QT-ifu">
+            <objects>
+                <viewController id="BYZ-38-t0r" customClass="FlutterViewController" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="y3c-jy-aDJ"/>
+                        <viewControllerLayoutGuide type="bottom" id="wfy-db-euE"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
+                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
+            </objects>
+        </scene>
+    </scenes>
+</document>

examples/catalog/ios/Runner/Info.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>animated_list</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>1.0</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>1</string>
+	<key>LSRequiresIPhoneOS</key>
+	<true/>
+	<key>UILaunchStoryboardName</key>
+	<string>LaunchScreen</string>
+	<key>UIMainStoryboardFile</key>
+	<string>Main</string>
+	<key>UISupportedInterfaceOrientations</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UISupportedInterfaceOrientations~ipad</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationPortraitUpsideDown</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UIViewControllerBasedStatusBarAppearance</key>
+	<false/>
+</dict>
+</plist>

examples/catalog/ios/Runner/main.m

+// Copyright 2014 The Flutter 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 <UIKit/UIKit.h>
+#import <Flutter/Flutter.h>
+#import "AppDelegate.h"
+
+int main(int argc, char * argv[]) {
+    @autoreleasepool {
+        return UIApplicationMain(argc, argv, nil,
+                                 NSStringFromClass([AppDelegate class]));
+    }
+}

examples/catalog/lib/animated_list.dart

+// Copyright 2014 The Flutter 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/foundation.dart';
+import 'package:flutter/material.dart';
+
+class AnimatedListSample extends StatefulWidget {
+  @override
+  _AnimatedListSampleState createState() => _AnimatedListSampleState();
+}
+
+class _AnimatedListSampleState extends State<AnimatedListSample> {
+  final GlobalKey<AnimatedListState> _listKey = GlobalKey<AnimatedListState>();
+  ListModel<int> _list;
+  int _selectedItem;
+  int _nextItem; // The next item inserted when the user presses the '+' button.
+
+  @override
+  void initState() {
+    super.initState();
+    _list = ListModel<int>(
+      listKey: _listKey,
+      initialItems: <int>[0, 1, 2],
+      removedItemBuilder: _buildRemovedItem,
+    );
+    _nextItem = 3;
+  }
+
+  // Used to build list items that haven't been removed.
+  Widget _buildItem(BuildContext context, int index, Animation<double> animation) {
+    return CardItem(
+      animation: animation,
+      item: _list[index],
+      selected: _selectedItem == _list[index],
+      onTap: () {
+        setState(() {
+          _selectedItem = _selectedItem == _list[index] ? null : _list[index];
+        });
+      },
+    );
+  }
+
+  // Used to build an item after it has been removed from the list. This method is
+  // needed because a removed item remains visible until its animation has
+  // completed (even though it's gone as far this ListModel is concerned).
+  // The widget will be used by the [AnimatedListState.removeItem] method's
+  // [AnimatedListRemovedItemBuilder] parameter.
+  Widget _buildRemovedItem(int item, BuildContext context, Animation<double> animation) {
+    return CardItem(
+      animation: animation,
+      item: item,
+      selected: false,
+      // No gesture detector here: we don't want removed items to be interactive.
+    );
+  }
+
+  // Insert the "next item" into the list model.
+  void _insert() {
+    final int index = _selectedItem == null ? _list.length : _list.indexOf(_selectedItem);
+    _list.insert(index, _nextItem++);
+  }
+
+  // Remove the selected item from the list model.
+  void _remove() {
+    if (_selectedItem != null) {
+      _list.removeAt(_list.indexOf(_selectedItem));
+      setState(() {
+        _selectedItem = null;
+      });
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('AnimatedList'),
+          actions: <Widget>[
+            IconButton(
+              icon: const Icon(Icons.add_circle),
+              onPressed: _insert,
+              tooltip: 'insert a new item',
+            ),
+            IconButton(
+              icon: const Icon(Icons.remove_circle),
+              onPressed: _remove,
+              tooltip: 'remove the selected item',
+            ),
+          ],
+        ),
+        body: Padding(
+          padding: const EdgeInsets.all(16.0),
+          child: AnimatedList(
+            key: _listKey,
+            initialItemCount: _list.length,
+            itemBuilder: _buildItem,
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+/// Keeps a Dart List in sync with an AnimatedList.
+///
+/// The [insert] and [removeAt] methods apply to both the internal list and the
+/// animated list that belongs to [listKey].
+///
+/// This class only exposes as much of the Dart List API as is needed by the
+/// sample app. More list methods are easily added, however methods that mutate the
+/// list must make the same changes to the animated list in terms of
+/// [AnimatedListState.insertItem] and [AnimatedList.removeItem].
+class ListModel<E> {
+  ListModel({
+    @required this.listKey,
+    @required this.removedItemBuilder,
+    Iterable<E> initialItems,
+  }) : assert(listKey != null),
+       assert(removedItemBuilder != null),
+       _items = initialItems?.toList() ?? <E>[];
+
+  final GlobalKey<AnimatedListState> listKey;
+  final Widget Function(E item, BuildContext context, Animation<double> animation) removedItemBuilder;
+  final List<E> _items;
+
+  AnimatedListState get _animatedList => listKey.currentState;
+
+  void insert(int index, E item) {
+    _items.insert(index, item);
+    _animatedList.insertItem(index);
+  }
+
+  E removeAt(int index) {
+    final E removedItem = _items.removeAt(index);
+    if (removedItem != null) {
+      _animatedList.removeItem(index, (BuildContext context, Animation<double> animation) {
+        return removedItemBuilder(removedItem, context, animation);
+      });
+    }
+    return removedItem;
+  }
+
+  int get length => _items.length;
+  E operator [](int index) => _items[index];
+  int indexOf(E item) => _items.indexOf(item);
+}
+
+/// Displays its integer item as 'item N' on a Card whose color is based on
+/// the item's value. The text is displayed in bright green if selected is true.
+/// This widget's height is based on the animation parameter, it varies
+/// from 0 to 128 as the animation varies from 0.0 to 1.0.
+class CardItem extends StatelessWidget {
+  const CardItem({
+    Key key,
+    @required this.animation,
+    this.onTap,
+    @required this.item,
+    this.selected = false,
+  }) : assert(animation != null),
+       assert(item != null && item >= 0),
+       assert(selected != null),
+       super(key: key);
+
+  final Animation<double> animation;
+  final VoidCallback onTap;
+  final int item;
+  final bool selected;
+
+  @override
+  Widget build(BuildContext context) {
+    TextStyle textStyle = Theme.of(context).textTheme.headline4;
+    if (selected)
+      textStyle = textStyle.copyWith(color: Colors.lightGreenAccent[400]);
+    return Padding(
+      padding: const EdgeInsets.all(2.0),
+      child: SizeTransition(
+        axis: Axis.vertical,
+        sizeFactor: animation,
+        child: GestureDetector(
+          behavior: HitTestBehavior.opaque,
+          onTap: onTap,
+          child: SizedBox(
+            height: 128.0,
+            child: Card(
+              color: Colors.primaries[item % Colors.primaries.length],
+              child: Center(
+                child: Text('Item $item', style: textStyle),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+void main() {
+  runApp(AnimatedListSample());
+}
+
+/*
+Sample Catalog
+
+Title: AnimatedList
+
+Summary: An AnimatedList for displaying a list of cards that stay
+in sync with an app-specific ListModel. When an item is added to or removed
+from the model, the corresponding card animates in or out of view.
+
+Description:
+Tap an item to select it, tap it again to unselect. Tap '+' to insert at the
+selected item, '-' to remove the selected item. The tap handlers add or
+remove items from a `ListModel<E>`, a simple encapsulation of `List<E>`
+that keeps the AnimatedList in sync. The list model has a GlobalKey for
+its animated list. It uses the key to call the insertItem and removeItem
+methods defined by AnimatedListState.
+
+Classes: AnimatedList, AnimatedListState
+
+Sample: AnimatedListSample
+
+See also:
+  - The "Components-Lists: Controls" section of the material design specification:
+    <https://material.io/guidelines/components/lists-controls.html#>
+*/

examples/catalog/lib/app_bar_bottom.dart

+// Copyright 2014 The Flutter 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/material.dart';
+
+class AppBarBottomSample extends StatefulWidget {
+  @override
+  _AppBarBottomSampleState createState() => _AppBarBottomSampleState();
+}
+
+class _AppBarBottomSampleState extends State<AppBarBottomSample> with SingleTickerProviderStateMixin {
+  TabController _tabController;
+
+  @override
+  void initState() {
+    super.initState();
+    _tabController = TabController(vsync: this, length: choices.length);
+  }
+
+  @override
+  void dispose() {
+    _tabController.dispose();
+    super.dispose();
+  }
+
+  void _nextPage(int delta) {
+    final int newIndex = _tabController.index + delta;
+    if (newIndex < 0 || newIndex >= _tabController.length)
+      return;
+    _tabController.animateTo(newIndex);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('AppBar Bottom Widget'),
+          leading: IconButton(
+            tooltip: 'Previous choice',
+            icon: const Icon(Icons.arrow_back),
+            onPressed: () { _nextPage(-1); },
+          ),
+          actions: <Widget>[
+            IconButton(
+              icon: const Icon(Icons.arrow_forward),
+              tooltip: 'Next choice',
+              onPressed: () { _nextPage(1); },
+            ),
+          ],
+          bottom: PreferredSize(
+            preferredSize: const Size.fromHeight(48.0),
+            child: Theme(
+              data: Theme.of(context).copyWith(accentColor: Colors.white),
+              child: Container(
+                height: 48.0,
+                alignment: Alignment.center,
+                child: TabPageSelector(controller: _tabController),
+              ),
+            ),
+          ),
+        ),
+        body: TabBarView(
+          controller: _tabController,
+          children: choices.map<Widget>((Choice choice) {
+            return Padding(
+              padding: const EdgeInsets.all(16.0),
+              child: ChoiceCard(choice: choice),
+            );
+          }).toList(),
+        ),
+      ),
+    );
+  }
+}
+
+class Choice {
+  const Choice({ this.title, this.icon });
+  final String title;
+  final IconData icon;
+}
+
+const List<Choice> choices = <Choice>[
+  Choice(title: 'CAR', icon: Icons.directions_car),
+  Choice(title: 'BICYCLE', icon: Icons.directions_bike),
+  Choice(title: 'BOAT', icon: Icons.directions_boat),
+  Choice(title: 'BUS', icon: Icons.directions_bus),
+  Choice(title: 'TRAIN', icon: Icons.directions_railway),
+  Choice(title: 'WALK', icon: Icons.directions_walk),
+];
+
+class ChoiceCard extends StatelessWidget {
+  const ChoiceCard({ Key key, this.choice }) : super(key: key);
+
+  final Choice choice;
+
+  @override
+  Widget build(BuildContext context) {
+    final TextStyle textStyle = Theme.of(context).textTheme.headline4;
+    return Card(
+      color: Colors.white,
+      child: Center(
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.center,
+          children: <Widget>[
+            Icon(choice.icon, size: 128.0, color: textStyle.color),
+            Text(choice.title, style: textStyle),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+void main() {
+  runApp(AppBarBottomSample());
+}
+
+/*
+Sample Catalog
+
+Title: AppBar with a custom bottom widget.
+
+Summary: An AppBar that includes a bottom widget. Any widget
+with a PreferredSize can appear at the bottom of an AppBar.
+
+Summary: Any widget with a PreferredSize can appear at the bottom of an AppBar.
+
+Description:
+Typically an AppBar's bottom widget is a TabBar however any widget with a
+PreferredSize can be used. In this app, the app bar's bottom widget is a
+TabPageSelector that displays the relative position of the selected page
+in the app's TabBarView. The arrow buttons in the toolbar part of the app
+bar and they select the previous or the next page.
+
+Classes: AppBar, PreferredSize, TabBarView, TabController
+
+Sample: AppBarBottomSample
+
+See also:
+  - The "Components-Tabs" section of the material design specification:
+    <https://material.io/go/design-tabs>
+*/

examples/catalog/lib/basic_app_bar.dart

+// Copyright 2014 The Flutter 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/material.dart';
+
+// This app is a stateful, it tracks the user's current choice.
+class BasicAppBarSample extends StatefulWidget {
+  @override
+  _BasicAppBarSampleState createState() => _BasicAppBarSampleState();
+}
+
+class _BasicAppBarSampleState extends State<BasicAppBarSample> {
+  Choice _selectedChoice = choices[0]; // The app's "state".
+
+  void _select(Choice choice) {
+    setState(() { // Causes the app to rebuild with the new _selectedChoice.
+      _selectedChoice = choice;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('Basic AppBar'),
+          actions: <Widget>[
+            IconButton( // action button
+              icon: Icon(choices[0].icon),
+              onPressed: () { _select(choices[0]); },
+            ),
+            IconButton( // action button
+              icon: Icon(choices[1].icon),
+              onPressed: () { _select(choices[1]); },
+            ),
+            PopupMenuButton<Choice>( // overflow menu
+              onSelected: _select,
+              itemBuilder: (BuildContext context) {
+                return choices.skip(2).map<PopupMenuItem<Choice>>((Choice choice) {
+                  return PopupMenuItem<Choice>(
+                    value: choice,
+                    child: Text(choice.title),
+                  );
+                }).toList();
+              },
+            ),
+          ],
+        ),
+        body: Padding(
+          padding: const EdgeInsets.all(16.0),
+          child: ChoiceCard(choice: _selectedChoice),
+        ),
+      ),
+    );
+  }
+}
+
+class Choice {
+  const Choice({ this.title, this.icon });
+  final String title;
+  final IconData icon;
+}
+
+const List<Choice> choices = <Choice>[
+  Choice(title: 'Car', icon: Icons.directions_car),
+  Choice(title: 'Bicycle', icon: Icons.directions_bike),
+  Choice(title: 'Boat', icon: Icons.directions_boat),
+  Choice(title: 'Bus', icon: Icons.directions_bus),
+  Choice(title: 'Train', icon: Icons.directions_railway),
+  Choice(title: 'Walk', icon: Icons.directions_walk),
+];
+
+class ChoiceCard extends StatelessWidget {
+  const ChoiceCard({ Key key, this.choice }) : super(key: key);
+
+  final Choice choice;
+
+  @override
+  Widget build(BuildContext context) {
+    final TextStyle textStyle = Theme.of(context).textTheme.headline4;
+    return Card(
+      color: Colors.white,
+      child: Center(
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.center,
+          children: <Widget>[
+            Icon(choice.icon, size: 128.0, color: textStyle.color),
+            Text(choice.title, style: textStyle),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+void main() {
+  runApp(BasicAppBarSample());
+}
+
+/*
+Sample Catalog
+
+Title: AppBar Basics
+
+Summary: A basic AppBar with a title, actions, and an overflow dropdown menu.
+
+Description:
+An app that displays one of a half dozen choices with an icon and a title.
+The two most common choices are available as action buttons and the remaining
+choices are included in the overflow dropdown menu.
+
+Classes: AppBar, IconButton, PopupMenuButton, Scaffold
+
+Sample: BasicAppBarSample
+
+See also:
+  - The "Layout-Structure" section of the material design specification:
+    <https://material.io/guidelines/layout/structure.html#structure-app-bar>
+*/

examples/catalog/lib/custom_semantics.dart

+// Copyright 2014 The Flutter 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/material.dart';
+
+/// A [ListTile] containing a dropdown menu that exposes itself as an
+/// "Adjustable" to screen readers (e.g. TalkBack on Android and VoiceOver on
+/// iOS).
+///
+/// This allows screen reader users to swipe up/down (on iOS) or use the volume
+/// keys (on Android) to switch between the values in the dropdown menu.
+/// Depending on what the values in the dropdown menu are this can be a more
+/// intuitive way of switching values compared to exposing the content of the
+/// drop down menu as a screen overlay from which the user can select.
+///
+/// Users that do not use a screen reader will just see a regular dropdown menu.
+class AdjustableDropdownListTile extends StatelessWidget {
+  const AdjustableDropdownListTile({
+    this.label,
+    this.value,
+    this.items,
+    this.onChanged,
+  });
+
+  final String label;
+  final String value;
+  final List<String> items;
+  final ValueChanged<String> onChanged;
+
+  @override
+  Widget build(BuildContext context) {
+    final int indexOfValue = items.indexOf(value);
+    assert(indexOfValue != -1);
+
+    final bool canIncrease = indexOfValue < items.length - 1;
+    final bool canDecrease = indexOfValue > 0;
+
+    return Semantics(
+      container: true,
+      label: label,
+      value: value,
+      increasedValue: canIncrease ? _increasedValue : null,
+      decreasedValue: canDecrease ? _decreasedValue : null,
+      onIncrease: canIncrease ? _performIncrease : null,
+      onDecrease: canDecrease ? _performDecrease : null,
+      child: ExcludeSemantics(
+        child: ListTile(
+          title: Text(label),
+          trailing: DropdownButton<String>(
+            value: value,
+            onChanged: onChanged,
+            items: items.map<DropdownMenuItem<String>>((String item) {
+              return DropdownMenuItem<String>(
+                value: item,
+                child: Text(item),
+              );
+            }).toList(),
+          ),
+        ),
+      ),
+    );
+  }
+
+  String get _increasedValue {
+    final int indexOfValue = items.indexOf(value);
+    assert(indexOfValue < items.length - 1);
+    return items[indexOfValue + 1];
+  }
+
+  String get _decreasedValue {
+    final int indexOfValue = items.indexOf(value);
+    assert(indexOfValue > 0);
+    return items[indexOfValue - 1];
+  }
+
+  void _performIncrease() => onChanged(_increasedValue);
+
+  void _performDecrease() => onChanged(_decreasedValue);
+}
+
+class AdjustableDropdownExample extends StatefulWidget {
+  @override
+  AdjustableDropdownExampleState createState() => AdjustableDropdownExampleState();
+}
+
+class AdjustableDropdownExampleState extends State<AdjustableDropdownExample> {
+
+  final List<String> items = <String>[
+    '1 second',
+    '5 seconds',
+    '15 seconds',
+    '30 seconds',
+    '1 minute',
+  ];
+  String timeout;
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('Adjustable DropDown'),
+        ),
+        body: ListView(
+          children: <Widget>[
+            AdjustableDropdownListTile(
+              label: 'Timeout',
+              value: timeout ?? items[2],
+              items: items,
+              onChanged: (String value) {
+                setState(() {
+                  timeout = value;
+                });
+              },
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+void main() {
+  runApp(AdjustableDropdownExample());
+}
+
+/*
+Sample Catalog
+
+Title: AdjustableDropdownListTile
+
+Summary: A dropdown menu that exposes itself as an "Adjustable" to screen
+readers.
+
+Description:
+This app presents a dropdown menu to the user that exposes itself as an
+"Adjustable" to screen readers (e.g. TalkBack on Android and VoiceOver on iOS).
+This allows users of screen readers to cycle through the values of the dropdown
+menu by swiping up or down on the screen with one finger (on iOS) or by using
+the volume keys (on Android). Depending on the values in the dropdown this
+behavior may be more intuitive to screen reader users compared to showing the
+classical dropdown overlay on screen to choose a value.
+
+When the screen reader is turned off, the dropdown menu behaves like any
+dropdown menu would.
+
+Classes: Semantics
+
+Sample: AdjustableDropdownListTile
+
+*/

examples/catalog/lib/expansion_tile_sample.dart

+// Copyright 2014 The Flutter 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/material.dart';
+
+class ExpansionTileSample extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        appBar: AppBar(
+          title: const Text('ExpansionTile'),
+        ),
+        body: ListView.builder(
+          itemBuilder: (BuildContext context, int index) => EntryItem(data[index]),
+          itemCount: data.length,
+        ),
+      ),
+    );
+  }
+}
+
+// One entry in the multilevel list displayed by this app.
+class Entry {
+  Entry(this.title, [this.children = const <Entry>[]]);
+  final String title;
+  final List<Entry> children;
+}
+
+// The entire multilevel list displayed by this app.
+final List<Entry> data = <Entry>[
+  Entry('Chapter A',
+    <Entry>[
+      Entry('Section A0',
+        <Entry>[
+          Entry('Item A0.1'),
+          Entry('Item A0.2'),
+          Entry('Item A0.3'),
+        ],
+      ),
+      Entry('Section A1'),
+      Entry('Section A2'),
+    ],
+  ),
+  Entry('Chapter B',
+    <Entry>[
+      Entry('Section B0'),
+      Entry('Section B1'),
+    ],
+  ),
+  Entry('Chapter C',
+    <Entry>[
+      Entry('Section C0'),
+      Entry('Section C1'),
+      Entry('Section C2',
+        <Entry>[
+          Entry('Item C2.0'),
+          Entry('Item C2.1'),
+          Entry('Item C2.2'),
+          Entry('Item C2.3'),
+        ],
+      ),
+    ],
+  ),
+];
+
+// Displays one Entry. If the entry has children then it's displayed
+// with an ExpansionTile.
+class EntryItem extends StatelessWidget {
+  const EntryItem(this.entry);
+
+  final Entry entry;
+
+  Widget _buildTiles(Entry root) {
+    if (root.children.isEmpty)
+      return ListTile(title: Text(root.title));
+    return ExpansionTile(
+      key: PageStorageKey<Entry>(root),
+      title: Text(root.title),
+      children: root.children.map<Widget>(_buildTiles).toList(),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return _buildTiles(entry);
+  }
+}
+
+void main() {
+  runApp(ExpansionTileSample());
+}
+
+/*
+Sample Catalog
+
+Title: ExpansionTile
+
+Summary: An ExpansionTile for building nested lists, with two or more levels.
+
+Description:
+This app displays hierarchical data with ExpansionTiles. Tapping a tile
+expands or collapses the view of its children. When a tile is collapsed
+its children are disposed so that the widget footprint of the list only
+reflects what's visible.
+
+When displayed within a scrollable that creates its list items lazily,
+like a scrollable list created with `ListView.builder()`, ExpansionTiles
+can be quite efficient, particularly for material design "expand/collapse"
+lists.
+
+
+Classes: ExpansionTile, ListView
+
+Sample: ExpansionTileSample
+
+See also:
+  - The "expand/collapse" part of the material design specification:
+    <https://material.io/guidelines/components/lists-controls.html#lists-controls-types-of-list-controls>
+*/

examples/catalog/lib/main.dart

+// Copyright 2014 The Flutter 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/widgets.dart';
+
+void main() {
+  runApp(
+    const Center(
+      child: Text(
+        'Instead run:\nflutter run lib/xxx.dart',
+        textDirection: TextDirection.ltr,
+      ),
+    ),
+  );
+}

examples/catalog/lib/tabbed_app_bar.dart

+// Copyright 2014 The Flutter 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/material.dart';
+
+class TabbedAppBarSample extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: DefaultTabController(
+        length: choices.length,
+        child: Scaffold(
+          appBar: AppBar(
+            title: const Text('Tabbed AppBar'),
+            bottom: TabBar(
+              isScrollable: true,
+              tabs: choices.map<Widget>((Choice choice) {
+                return Tab(
+                  text: choice.title,
+                  icon: Icon(choice.icon),
+                );
+              }).toList(),
+            ),
+          ),
+          body: TabBarView(
+            children: choices.map<Widget>((Choice choice) {
+              return Padding(
+                padding: const EdgeInsets.all(16.0),
+                child: ChoiceCard(choice: choice),
+              );
+            }).toList(),
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class Choice {
+  const Choice({ this.title, this.icon });
+  final String title;
+  final IconData icon;
+}
+
+const List<Choice> choices = <Choice>[
+  Choice(title: 'CAR', icon: Icons.directions_car),
+  Choice(title: 'BICYCLE', icon: Icons.directions_bike),
+  Choice(title: 'BOAT', icon: Icons.directions_boat),
+  Choice(title: 'BUS', icon: Icons.directions_bus),
+  Choice(title: 'TRAIN', icon: Icons.directions_railway),
+  Choice(title: 'WALK', icon: Icons.directions_walk),
+];
+
+class ChoiceCard extends StatelessWidget {
+  const ChoiceCard({ Key key, this.choice }) : super(key: key);
+
+  final Choice choice;
+
+  @override
+  Widget build(BuildContext context) {
+    final TextStyle textStyle = Theme.of(context).textTheme.headline4;
+    return Card(
+      color: Colors.white,
+      child: Center(
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.center,
+          children: <Widget>[
+            Icon(choice.icon, size: 128.0, color: textStyle.color),
+            Text(choice.title, style: textStyle),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+void main() {
+  runApp(TabbedAppBarSample());
+}
+
+/*
+Sample Catalog
+
+Title: Tabbed AppBar
+
+Summary: An AppBar with a TabBar for navigating pages just below it.
+
+Description:
+A TabBar can be used to navigate among the pages displayed in a TabBarView.
+Although a TabBar is an ordinary widget that can appear anywhere, it's most often
+included in the application's AppBar.
+
+Classes: AppBar, DefaultTabController, TabBar, Scaffold, TabBarView
+
+Sample: TabbedAppBarSample
+
+See also:
+  - The "Components-Tabs" section of the material design specification:
+    <https://material.io/go/design-tabs>
+*/

examples/catalog/pubspec.yaml

+name: sample_catalog
+description: A collection of Flutter sample apps
+
+environment:
+  # The pub client defaults to an <2.0.0 sdk constraint which we need to explicitly overwrite.
+  sdk: ">=2.0.0-dev.68.0 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  path: 1.8.0-nullsafety.1
+
+  characters: 1.1.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  collection: 1.15.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  meta: 1.3.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  typed_data: 1.3.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  vector_math: 2.1.0-nullsafety.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+  flutter_driver:
+    sdk: flutter
+  test: 1.16.0-nullsafety.5
+
+  _fe_analyzer_shared: 7.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  analyzer: 0.39.17 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  archive: 2.0.13 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  args: 1.6.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  async: 2.5.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  boolean_selector: 2.1.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  charcode: 1.2.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  cli_util: 0.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  clock: 1.1.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  convert: 2.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  coverage: 0.14.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  crypto: 2.1.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  csslib: 0.16.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  fake_async: 1.2.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  file: 6.0.0-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  glob: 1.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  html: 0.14.0+3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  http: 0.12.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  http_multi_server: 2.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  http_parser: 3.1.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  io: 0.3.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  js: 0.6.3-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  json_rpc_2: 2.2.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  logging: 0.11.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  matcher: 0.12.10-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  mime: 0.9.7 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  node_interop: 1.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  node_io: 1.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  node_preamble: 1.4.12 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  package_config: 1.9.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  pedantic: 1.10.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  pool: 1.5.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  pub_semver: 1.4.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf: 0.7.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_packages_handler: 2.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_static: 0.2.8 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_web_socket: 0.2.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_map_stack_trace: 2.1.0-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_maps: 0.10.10-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_span: 1.8.0-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  stack_trace: 1.10.0-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  stream_channel: 2.1.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  string_scanner: 1.1.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  sync_http: 0.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  term_glyph: 1.2.0-nullsafety.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  test_api: 0.2.19-nullsafety.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  test_core: 0.3.12-nullsafety.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  vm_service: 4.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  vm_service_client: 0.2.6+2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  watcher: 0.9.7+15 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  web_socket_channel: 1.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  webdriver: 2.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  webkit_inspection_protocol: 0.7.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  yaml: 2.2.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+
+flutter:
+  uses-material-design: true
+
+# PUBSPEC CHECKSUM: 5ffe

examples/catalog/test/animated_list_test.dart

+// Copyright 2014 The Flutter 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/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/animated_list.dart' as animated_list_sample;
+
+void main() {
+  testWidgets('animated_list sample app smoke test', (WidgetTester tester) async {
+    animated_list_sample.main();
+    await tester.pump();
+
+    expect(find.text('Item 0'), findsOneWidget);
+    expect(find.text('Item 1'), findsOneWidget);
+    expect(find.text('Item 2'), findsOneWidget);
+
+    final Finder insertButton = find.byTooltip('insert a new item');
+    final Finder removeButton = find.byTooltip('remove the selected item');
+    expect(insertButton, findsOneWidget);
+    expect(removeButton, findsOneWidget);
+
+    // Remove items 0, 1, 2.
+    await tester.tap(find.text('Item 0'));
+    await tester.tap(removeButton);
+    await tester.pumpAndSettle();
+    await tester.tap(find.text('Item 1'));
+    await tester.tap(removeButton);
+    await tester.pumpAndSettle();
+    await tester.tap(find.text('Item 2'));
+    await tester.tap(removeButton);
+    await tester.pumpAndSettle();
+
+    // Append items 3, 4, 5, 6.
+    await tester.tap(insertButton);
+    await tester.tap(insertButton);
+    await tester.tap(insertButton);
+    await tester.tap(insertButton);
+    await tester.pumpAndSettle();
+
+    expect(find.text('Item 0'), findsNothing);
+    expect(find.text('Item 1'), findsNothing);
+    expect(find.text('Item 2'), findsNothing);
+    expect(find.text('Item 3'), findsOneWidget);
+    expect(find.text('Item 4'), findsOneWidget);
+    expect(find.text('Item 5'), findsOneWidget);
+    expect(find.text('Item 6'), findsOneWidget);
+
+    // Insert items 7, 8 at item 3's position (at the top)
+    await tester.tap(find.text('Item 3'));
+    await tester.tap(insertButton);
+    await tester.tap(insertButton);
+    await tester.pumpAndSettle();
+
+    expect(find.text('Item 7'), findsOneWidget);
+    expect(find.text('Item 8'), findsOneWidget);
+
+    // Scroll to the end.
+    await tester.fling(find.text('Item 7'), const Offset(0.0, -200.0), 1000.0);
+    await tester.pumpAndSettle();
+    expect(find.text('Item 6'), findsOneWidget);
+    expect(find.text('Item 8'), findsNothing);
+  });
+}

examples/catalog/test/app_bar_bottom_test.dart

+// Copyright 2014 The Flutter 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/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/app_bar_bottom.dart' as app_bar_bottom_sample;
+
+final int choiceCount = app_bar_bottom_sample.choices.length;
+IconData iconAt(int index) => app_bar_bottom_sample.choices[index].icon;
+
+Finder findChoiceCard(IconData icon) {
+  return find.descendant(of: find.byType(Card), matching: find.byIcon(icon));
+}
+
+void main() {
+  testWidgets('app_bar_bottom sample smoke test', (WidgetTester tester) async {
+    app_bar_bottom_sample.main();
+    await tester.pump();
+
+    // Cycle through the choices using the forward and backwards arrows.
+
+    final Finder nextChoice = find.byTooltip('Next choice');
+    for (int i = 0; i < choiceCount; i += 1) {
+      expect(findChoiceCard(iconAt(i)), findsOneWidget);
+      await tester.tap(nextChoice);
+      await tester.pumpAndSettle();
+    }
+
+    final Finder previousChoice = find.byTooltip('Previous choice');
+    for (int i = choiceCount - 1; i >= 0; i -= 1) {
+      expect(findChoiceCard(iconAt(i)), findsOneWidget);
+      await tester.tap(previousChoice);
+      await tester.pumpAndSettle();
+    }
+  });
+}

examples/catalog/test/basic_app_bar_test.dart

+// Copyright 2014 The Flutter 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/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/basic_app_bar.dart' as basic_app_bar_sample;
+
+int choiceCount = basic_app_bar_sample.choices.length;
+IconData iconAt(int index) => basic_app_bar_sample.choices[index].icon;
+String titleAt(int index) => basic_app_bar_sample.choices[index].title;
+
+Finder findAppBarIcon(IconData icon) {
+  return find.descendant(of: find.byType(AppBar), matching: find.byIcon(icon));
+}
+
+Finder findChoiceCard(IconData icon) {
+  return find.descendant(of: find.byType(Card), matching: find.byIcon(icon));
+}
+
+void main() {
+  testWidgets('basic_app_bar sample smoke test', (WidgetTester tester) async {
+    basic_app_bar_sample.main();
+    await tester.pump();
+
+    // Tap on the two action buttons and all of the overflow menu items.
+    // Verify that a Card with the expected icon appears.
+
+    await tester.tap(findAppBarIcon(iconAt(0)));
+    await tester.pumpAndSettle();
+    expect(findChoiceCard(iconAt(0)), findsOneWidget);
+
+    await tester.tap(findAppBarIcon(iconAt(1)));
+    await tester.pumpAndSettle();
+    expect(findChoiceCard(iconAt(1)), findsOneWidget);
+
+    for (int i = 2; i < choiceCount; i += 1) {
+      await tester.tap(findAppBarIcon(Icons.more_vert));
+      await tester.pumpAndSettle();
+      await tester.tap(find.text(titleAt(i)));
+      await tester.pumpAndSettle();
+      expect(findChoiceCard(iconAt(i)), findsOneWidget);
+    }
+  });
+}

examples/catalog/test/custom_semantics_test.dart

+// Copyright 2014 The Flutter 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/rendering.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/custom_semantics.dart' as custom_semantics show main;
+import 'package:sample_catalog/custom_semantics.dart';
+
+void main() {
+  testWidgets('custom_semantics sample smoke test', (WidgetTester tester) async {
+    // Turn on Semantics
+    final SemanticsHandle semanticsHandler = tester.binding.pipelineOwner.ensureSemantics();
+    final SemanticsOwner semanticsOwner = tester.binding.pipelineOwner.semanticsOwner;
+
+    // Build the sample app
+    custom_semantics.main();
+    await tester.pump();
+
+    // Verify it correctly exposes its semantics.
+    final SemanticsNode semantics = tester.getSemantics(find.byType(AdjustableDropdownListTile));
+
+    expectAdjustable(semantics,
+      hasIncreaseAction: true,
+      hasDecreaseAction: true,
+      label: 'Timeout',
+      decreasedValue: '5 seconds',
+      value: '15 seconds',
+      increasedValue: '30 seconds',
+    );
+
+    // Increase
+    semanticsOwner.performAction(semantics.id, SemanticsAction.increase);
+    await tester.pump();
+
+    expectAdjustable(semantics,
+      hasIncreaseAction: true,
+      hasDecreaseAction: true,
+      label: 'Timeout',
+      decreasedValue: '15 seconds',
+      value: '30 seconds',
+      increasedValue: '1 minute',
+    );
+
+    // Increase all the way to highest value
+    semanticsOwner.performAction(semantics.id, SemanticsAction.increase);
+    await tester.pump();
+
+    expectAdjustable(semantics,
+      hasIncreaseAction: false,
+      hasDecreaseAction: true,
+      label: 'Timeout',
+      decreasedValue: '30 seconds',
+      value: '1 minute',
+    );
+
+    // Decrease
+    semanticsOwner.performAction(semantics.id, SemanticsAction.decrease);
+    await tester.pump();
+
+    expectAdjustable(semantics,
+      hasIncreaseAction: true,
+      hasDecreaseAction: true,
+      label: 'Timeout',
+      decreasedValue: '15 seconds',
+      value: '30 seconds',
+      increasedValue: '1 minute',
+    );
+
+    // Decrease all the way to lowest value
+    semanticsOwner.performAction(semantics.id, SemanticsAction.decrease);
+    await tester.pump();
+    semanticsOwner.performAction(semantics.id, SemanticsAction.decrease);
+    await tester.pump();
+    semanticsOwner.performAction(semantics.id, SemanticsAction.decrease);
+    await tester.pump();
+
+    expectAdjustable(semantics,
+      hasIncreaseAction: true,
+      hasDecreaseAction: false,
+      label: 'Timeout',
+      value: '1 second',
+      increasedValue: '5 seconds',
+    );
+
+    // Clean-up
+    semanticsHandler.dispose();
+  });
+}
+
+void expectAdjustable(
+  SemanticsNode node, {
+  bool hasIncreaseAction = true,
+  bool hasDecreaseAction = true,
+  String label = '',
+  String decreasedValue = '',
+  String value = '',
+  String increasedValue = '',
+}) {
+  final SemanticsData semanticsData = node.getSemanticsData();
+
+  int actions = 0;
+  if (hasIncreaseAction)
+    actions |= SemanticsAction.increase.index;
+  if (hasDecreaseAction)
+    actions |= SemanticsAction.decrease.index;
+
+  expect(semanticsData.actions, actions);
+  expect(semanticsData.label, label);
+  expect(semanticsData.decreasedValue, decreasedValue);
+  expect(semanticsData.value, value);
+  expect(semanticsData.increasedValue, increasedValue);
+}

examples/catalog/test/expansion_tile_sample_test.dart

+// Copyright 2014 The Flutter 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/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/expansion_tile_sample.dart' as expansion_tile_sample;
+import 'package:sample_catalog/expansion_tile_sample.dart' show Entry;
+
+void main() {
+  testWidgets('expansion_tile sample smoke test', (WidgetTester tester) async {
+    expansion_tile_sample.main();
+    await tester.pump();
+
+    // Initially only the top level EntryItems (the "chapters") are present.
+    for (final Entry chapter in expansion_tile_sample.data) {
+      expect(find.text(chapter.title), findsOneWidget);
+      for (final Entry section in chapter.children) {
+        expect(find.text(section.title), findsNothing);
+        for (final Entry item in section.children)
+          expect(find.text(item.title), findsNothing);
+      }
+    }
+
+    Future<void> scrollUpOneEntry() async {
+      await tester.dragFrom(const Offset(200.0, 200.0), const Offset(0.0, -88.00));
+      await tester.pumpAndSettle();
+    }
+
+    Future<void> tapEntry(String title) async {
+      await tester.tap(find.text(title));
+      await tester.pumpAndSettle();
+    }
+
+    // Expand the chapters. Now the chapter and sections, but not the
+    // items, should be present.
+    for (final Entry chapter in expansion_tile_sample.data.reversed)
+      await tapEntry(chapter.title);
+
+    for (final Entry chapter in expansion_tile_sample.data) {
+      expect(find.text(chapter.title), findsOneWidget);
+      for (final Entry section in chapter.children) {
+        expect(find.text(section.title), findsOneWidget);
+        await scrollUpOneEntry();
+        for (final Entry item in section.children)
+          expect(find.text(item.title), findsNothing);
+      }
+      await scrollUpOneEntry();
+    }
+
+    // - scroll to the top -
+    await tester.flingFrom(const Offset(200.0, 200.0), const Offset(0.0, 100.0), 5000.0);
+    await tester.pumpAndSettle();
+
+    // Expand the sections. Now Widgets for all three levels should be present.
+    for (final Entry chapter in expansion_tile_sample.data) {
+      for (final Entry section in chapter.children) {
+        await tapEntry(section.title);
+        await scrollUpOneEntry();
+      }
+      await scrollUpOneEntry();
+    }
+
+    // We're scrolled to the bottom so the very last item is visible.
+    // Working in reverse order, so we don't need to do anymore scrolling,
+    // check that everything is visible and close the sections and
+    // chapters as we go up.
+    for (final Entry chapter in expansion_tile_sample.data.reversed) {
+      expect(find.text(chapter.title), findsOneWidget);
+      for (final Entry section in chapter.children.reversed) {
+        expect(find.text(section.title), findsOneWidget);
+        for (final Entry item in section.children.reversed)
+          expect(find.text(item.title), findsOneWidget);
+        await tapEntry(section.title); // close the section
+      }
+      await tapEntry(chapter.title); // close the chapter
+    }
+
+    // Finally only the top level EntryItems (the "chapters") are present.
+    for (final Entry chapter in expansion_tile_sample.data) {
+      expect(find.text(chapter.title), findsOneWidget);
+      for (final Entry section in chapter.children) {
+        expect(find.text(section.title), findsNothing);
+        for (final Entry item in section.children)
+          expect(find.text(item.title), findsNothing);
+      }
+    }
+
+  });
+}

examples/catalog/test/tabbed_app_bar_test.dart

+// Copyright 2014 The Flutter 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/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sample_catalog/tabbed_app_bar.dart' as tabbed_app_bar_sample;
+
+final int choiceCount = tabbed_app_bar_sample.choices.length;
+IconData iconAt(int index) => tabbed_app_bar_sample.choices[index].icon;
+
+Finder findChoiceCard(IconData icon) {
+  return find.descendant(of: find.byType(Card), matching: find.byIcon(icon));
+}
+
+Finder findTab(IconData icon) {
+  return find.descendant(of: find.byType(Tab), matching: find.byIcon(icon));
+}
+
+void main() {
+  testWidgets('tabbed_app_bar sample smoke test', (WidgetTester tester) async {
+    tabbed_app_bar_sample.main();
+    await tester.pump();
+
+    // Tap on each tab, verify that a Card with the expected icon appears.
+    for (int i = 0; i < choiceCount; i += 1) {
+      await tester.tap(findTab(iconAt(i)));
+      await tester.pumpAndSettle();
+      expect(findChoiceCard(iconAt(i)), findsOneWidget);
+      // Scroll the tabBar by about one tab width
+      await tester.drag(find.byType(TabBar), const Offset(-24.0, 0.0));
+      await tester.pumpAndSettle();
+    }
+  });
+}

examples/catalog/test_driver/README.md

+The screenshot.dart and screenshot_test.dart files were generated by ../bin/sample_page.dart. They should not be checked in.