Initial commit

.gitignore

+.DS_Store
+.idea/
+*.iml

.metadata

+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: 2d2a1ffec95cc70a3218872a2cd3f8de4933c42f
+  channel: stable
+
+project_type: package

CHANGELOG.md

+## 2.1.1 - 2023.01.30
+
+* Support `dark` theme.
+
+## 2.1.0 - 2023.01.29
+
+* Follow the file naming convention in Effective Dart, #59
+* fix: AM/PM are backward for 12:00, #185
+* added ROMANIAN localization
+
+## 2.0.5 - 2022.07.19
+
+* close debug log (#178)
+
+## 2.0.4 - 2022.06.28
+
+* Add `PickerLocalizations.registerCustomLanguage` function
+* Add `onBuilderItem` params. Allow custom item to be generated.
+* Fixed bug: #158, #168, #169, #177
+
+## 2.0.3 - 2022.02.212
+
+* Fixed bug: #161, #165 ...
+* Add `onBuilder`, `backgroundColor` parameter to `show`, `showDialog`, `showModal`
+
+## 2.0.2 - 2021.06.25
+
+* Fixed bug: #142, #98
+* Add demo DurationPicker
+* Add onConfirmBefore callback event;
+
+## 2.0.1
+* Fixed bug.
+* Add PickerWidget.of(context) Get Picker
+* Add selectedIconTheme property
+
+## 2.0.0
+* Support Null safety
+* Optimize code, Update demo list
+
+## 1.1.5
+* Repair BUG (Including the problem of datetime adapter before the month, add the needUpdatePrev interface to the adapter)
+* add builderHeader params. Allow custom headers to be generated.
+* DateTimePickerAdapter add minHour, maxHour.
+* Thank you for your timely feedback in GitHub!
+
+## 1.1.4
+* performance optimization
+* Add a demo with a pop-up fillet background at the bottom.
+
+## 1.1.3
+* return for showDialog , add barrierDismissible (thanks: Ali1Ammar)
+
+## 1.1.2
+* Add the ability to jump minutes in DateTimePickerAdapter #76 (thank: MoacirSchmidt)
+* Repair BUG
+
+## 1.1.1
+* Add localization for Turkish language
+* Refactor localization code
+* Repair BUG
+
+## 1.1.0
+
+* Project reconstruction, removing Android, IOS directory. 
+* Add localization for Spanish language
+
+## 1.0.15
+
+* Move the edge of the head to the bottom of the head so that it can be hidden by customization. #55 (thank: @StarOfLife)
+* Repair bug: .showDialog(context) - error for define style #49 (thank: @nielgomes)
+* Repair bug: Change superior data, lower data display blank #48 (thank: @DemoJameson)
+
+## 1.0.14
+
+* Added return for showModal #44 (thank: @GiorgioBertolotti)
+
+## 1.0.13
+
+* Add parameter: selectedTextStyle, Styles for setting selected items. (thank: @TristanWYL)
+* Add parameter: footer, Widgets can be added at the bottom.
+
+## 1.0.12
+
+* Repair BUG: #38, #40
+* DateTimePickerAdapter: Add the twoDigitYear attribute to support small screens (#39)
+
+## 1.0.11
+
+* Add localization for Arabic language
+* Add parameter: cancel and confirm,  Allow yourself to specify widgets to be placed in the identified and cancelled locations
+* DateTimePickerAdapter supports minValue and maxValue, which are used to limit the upper and lower bounds for selecting date and time.
+
+## 1.0.10
+
+* Solving #25 Problem  
+* Add attributes: headerDecoration, Can be used to control header borders.
+* Add Italian locale.
+
+## 1.0.9
+
+* Add the ability to jump numbers in NumberPickerColumn (thank: @jesusrp98)
+
+## 1.0.8
+
+* Repair Bug: showDialog
+
+## 1.0.7
+
+* Add korea locale
+
+## 1.0.6
+
+* Remove debugging output information
+
+## 1.0.5
+
+* Modifying description information
+
+## 1.0.3
+
+* Repair Bug.
+* NumberPickerAdapter, data Add onFormatValue property
+* DateTimePickerAdapter, Add customColumnType property, Support custom column order.
+
+## 1.0.2
+
+* Repair Bug.
+
+## 1.0.1
+
+* NumberPickerAdapter Support postfix; suffix.
+
+## 1.0.0
+
+* Add NumberPickerAdapter, Support specified number range
+* Add isLinkage property, Support Array.
+* Add delimiter, Insert separators between columns
+* Add localization support
+* Optimization code
+
+## 0.0.5
+
+* Adapter add notifyDataChanged function.
+
+## 0.0.4
+
+*  Add PickerDateTimeType.kYM.
+
+## 0.0.3
+
+* Support column Flex setting. Add new DateTimeAdapter type.
+
+## 0.0.2
+
+* Code refactoring, adding adapters. Support dialog box. Increase the date and time selection.
+
+
+## 0.0.1
+
+* Describe initial release.

LICENSE

+MIT License
+
+Copyright (c) 2018 - 2019
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

+# flutter_picker
+
+[![pub package](https://img.shields.io/pub/v/flutter_picker.svg)](https://pub.dartlang.org/packages/flutter_picker)
+![GitHub](https://img.shields.io/github/license/yangyxd/flutter_picker.svg)
+[![GitHub stars](https://img.shields.io/github/stars/yangyxd/flutter_picker.svg?style=social&label=Stars)](https://github.com/yangyxd/flutter_picker)
+
+Flutter plugin picker. Include NumberPicker, DateTimePicker, ArrayPicker, and default linkage Picker. Provide flexible parameters to meet various needs. At the same time, you can extend more functions through custom adapters.
+
+> Supported  Platforms
+> * Android
+> * IOS
+> * Windows
+> * MacOS
+> * Linux
+> * Web
+
+![image](https://github.com/yangyxd/flutter_picker/blob/master/raw/views.gif)
+
+## How to Use
+
+```yaml
+# add this line to your dependencies
+flutter_picker:
+  git:
+    url: https://github.com/yangyxd/flutter_picker.git
+```
+```dart
+import 'package:flutter_picker/flutter_picker.dart';
+```
+
+```dart
+
+    showPicker(BuildContext context) {
+      Picker picker = new Picker(
+        adapter: PickerDataAdapter<String>(pickerdata: new JsonDecoder().convert(PickerData)),
+        changeToFirst: true,
+        textAlign: TextAlign.left,
+        columnPadding: const EdgeInsets.all(8.0),
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.getSelectedValues());
+        }
+      );
+      picker.show(_scaffoldKey.currentState);
+    }
+
+    showPickerModal(BuildContext context) {
+      new Picker(
+        adapter: PickerDataAdapter<String>(pickerdata: new JsonDecoder().convert(PickerData)),
+        changeToFirst: true,
+        hideHeader: false,
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.adapter.text);
+        }
+      ).showModal(this.context); //_scaffoldKey.currentState);
+    }
+
+    showPickerIcons(BuildContext context) {
+      new Picker(
+        adapter: PickerDataAdapter(data: [
+          new PickerItem(text: Icon(Icons.add), value: Icons.add, children: [
+            new PickerItem(text: Icon(Icons.more)),
+            new PickerItem(text: Icon(Icons.aspect_ratio)),
+            new PickerItem(text: Icon(Icons.android)),
+            new PickerItem(text: Icon(Icons.menu)),
+          ]),
+          new PickerItem(text: Icon(Icons.title), value: Icons.title, children: [
+            new PickerItem(text: Icon(Icons.more_vert)),
+            new PickerItem(text: Icon(Icons.ac_unit)),
+            new PickerItem(text: Icon(Icons.access_alarm)),
+            new PickerItem(text: Icon(Icons.account_balance)),
+          ]),
+          new PickerItem(text: Icon(Icons.face), value: Icons.face, children: [
+            new PickerItem(text: Icon(Icons.add_circle_outline)),
+            new PickerItem(text: Icon(Icons.add_a_photo)),
+            new PickerItem(text: Icon(Icons.access_time)),
+            new PickerItem(text: Icon(Icons.adjust)),
+          ]),
+          new PickerItem(text: Icon(Icons.linear_scale), value: Icons.linear_scale, children: [
+            new PickerItem(text: Icon(Icons.assistant_photo)),
+            new PickerItem(text: Icon(Icons.account_balance)),
+            new PickerItem(text: Icon(Icons.airline_seat_legroom_extra)),
+            new PickerItem(text: Icon(Icons.airport_shuttle)),
+            new PickerItem(text: Icon(Icons.settings_bluetooth)),
+          ]),
+          new PickerItem(text: Icon(Icons.close), value: Icons.close),
+        ]),
+        title: new Text("Select Icon"),
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.getSelectedValues());
+        }
+    ).show(_scaffoldKey.currentState);
+  }
+
+  showPickerDialog(BuildContext context) {
+    new Picker(
+        adapter: PickerDataAdapter<String>(pickerdata: new JsonDecoder().convert(PickerData)),
+        hideHeader: true,
+        title: new Text("Select Data"),
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.getSelectedValues());
+        }
+    ).showDialog(context);
+  }
+
+  showPickerArray(BuildContext context) {
+    new Picker(
+        adapter: PickerDataAdapter<String>(pickerdata: new JsonDecoder().convert(PickerData2), isArray: true),
+        hideHeader: true,
+        title: new Text("Please Select"),
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.getSelectedValues());
+        }
+    ).showDialog(context);
+  }
+
+  showPickerNumber(BuildContext context) {
+    new Picker(
+        adapter: NumberPickerAdapter(data: [
+          NumberPickerColumn(begin: 0, end: 999),
+          NumberPickerColumn(begin: 100, end: 200),
+        ]),
+        delimiter: [
+          PickerDelimiter(child: Container(
+            width: 30.0,
+            alignment: Alignment.center,
+            child: Icon(Icons.more_vert),
+          ))
+        ],
+        hideHeader: true,
+        title: new Text("Please Select"),
+        onConfirm: (Picker picker, List value) {
+          print(value.toString());
+          print(picker.getSelectedValues());
+        }
+    ).showDialog(context);
+  }
+
+```
+## PickerData Example
+
+### Array
+
+```dart
+
+const PickerData2 = '''
+[
+    [
+        1,
+        2,
+        3,
+        4
+    ],
+    [
+        11,
+        22,
+        33,
+        44
+    ],
+    [
+        "aaa",
+        "bbb",
+        "ccc"
+    ]
+]
+    ''';
+```
+
+### Linkage
+```dart
+const PickerData = '''
+[
+    {
+        "a": [
+            {
+                "a1": [
+                    1,
+                    2,
+                    3,
+                    4
+                ]
+            },
+            {
+                "a2": [
+                    5,
+                    6,
+                    7,
+                    8
+                ]
+            },
+            {
+                "a3": [
+                    9,
+                    10,
+                    11,
+                    12
+                ]
+            }
+        ]
+    },
+    {
+        "b": [
+            {
+                "b1": [
+                    11,
+                    22,
+                    33,
+                    44
+                ]
+            },
+            {
+                "b2": [
+                    55,
+                    66,
+                    77,
+                    88
+                ]
+            },
+            {
+                "b3": [
+                    99,
+                    1010,
+                    1111,
+                    1212
+                ]
+            }
+        ]
+    },
+    {
+        "c": [
+            {
+                "c1": [
+                    "a",
+                    "b",
+                    "c"
+                ]
+            },
+            {
+                "c2": [
+                    "aa",
+                    "bb",
+                    "cc"
+                ]
+            },
+            {
+                "c3": [
+                    "aaa",
+                    "bbb",
+                    "ccc"
+                ]
+            }
+        ]
+    }
+]
+    ''';
+```
\ No newline at end of file

example/.gitignore

+.DS_Store
+.dart_tool/
+
+.packages
+.pub/
+
+build/
+
+.flutter-plugins

example/.metadata

+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled.
+
+version:
+  revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+  channel: stable
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: android
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: ios
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: linux
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: macos
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: web
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+    - platform: windows
+      create_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+      base_revision: cd41fdd495f6944ecd3506c21e94c6567b073278
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'

example/README.md

+# flutter_picker_example
+
+Demonstrates how to use the flutter_picker plugin.
+
+## Getting Started
+
+For help getting started with Flutter, view our online
+[documentation](https://flutter.io/).

example/analysis_options.yaml

+# This file configures the analyzer, which statically analyzes Dart code to
+# check for errors, warnings, and lints.
+#
+# The issues identified by the analyzer are surfaced in the UI of Dart-enabled
+# IDEs (https://dart.dev/tools#ides-and-editors). The analyzer can also be
+# invoked from the command line by running `flutter analyze`.
+
+# The following line activates a set of recommended lints for Flutter apps,
+# packages, and plugins designed to encourage good coding practices.
+include: package:flutter_lints/flutter.yaml
+
+linter:
+  # The lint rules applied to this project can be customized in the
+  # section below to disable rules from the `package:flutter_lints/flutter.yaml`
+  # included above or to enable additional rules. A list of all available lints
+  # and their documentation is published at
+  # https://dart-lang.github.io/linter/lints/index.html.
+  #
+  # Instead of disabling a lint rule for the entire project in the
+  # section below, it can also be suppressed for a single line of code
+  # or a specific dart file by using the `// ignore: name_of_lint` and
+  # `// ignore_for_file: name_of_lint` syntax on the line or in the file
+  # producing the lint.
+  rules:
+    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
+    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+
+# Additional information about this file can be found at
+# https://dart.dev/guides/language/analysis-options

example/android/.gitignore

+gradle-wrapper.jar
+/.gradle
+/captures/
+/gradlew
+/gradlew.bat
+/local.properties
+GeneratedPluginRegistrant.java
+
+# Remember to never publicly share your keystore.
+# See https://flutter.dev/docs/deployment/android#reference-the-keystore-from-the-app
+key.properties
+**/*.keystore
+**/*.jks

example/android/app/build.gradle

+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 plugin: 'kotlin-android'
+apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+
+android {
+    compileSdkVersion flutter.compileSdkVersion
+    ndkVersion flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    kotlinOptions {
+        jvmTarget = '1.8'
+    }
+
+    sourceSets {
+        main.java.srcDirs += 'src/main/kotlin'
+    }
+
+    defaultConfig {
+        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
+        applicationId "com.yangyxd.example"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-build-configuration.
+        minSdkVersion flutter.minSdkVersion
+        targetSdkVersion flutter.targetSdkVersion
+        versionCode flutterVersionCode.toInteger()
+        versionName flutterVersionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig signingConfigs.debug
+        }
+    }
+}
+
+flutter {
+    source '../..'
+}
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+}

example/android/app/src/debug/AndroidManifest.xml

+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.yangyxd.example">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

example/android/app/src/main/AndroidManifest.xml

+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.yangyxd.example">
+   <application
+        android:label="example"
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:launchMode="singleTop"
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
+            <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>

example/android/app/src/main/kotlin/com/yangyxd/example/MainActivity.kt

+package com.yangyxd.example
+
+import io.flutter.embedding.android.FlutterActivity
+
+class MainActivity: FlutterActivity() {
+}

example/android/app/src/main/res/drawable-v21/launch_background.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="?android:colorBackground" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>

example/android/app/src/main/res/drawable/launch_background.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="@android:color/white" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>

example/android/app/src/main/res/values-night/styles.xml

+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is on -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>

example/android/app/src/main/res/values/styles.xml

+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is off -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>

example/android/app/src/profile/AndroidManifest.xml

+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.yangyxd.example">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>

example/android/build.gradle

+buildscript {
+    ext.kotlin_version = '1.6.10'
+    repositories {
+        google()
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:7.1.2'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+    }
+}
+
+allprojects {
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+
+rootProject.buildDir = '../build'
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+}
+subprojects {
+    project.evaluationDependsOn(':app')
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}

example/android/gradle.properties

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

example/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-7.4-all.zip

example/android/settings.gradle

+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"

example/ios/.gitignore

+.idea/
+.vagrant/
+.sconsign.dblite
+.svn/
+
+.DS_Store
+*.swp
+profile
+
+DerivedData/
+build/
+GeneratedPluginRegistrant.h
+GeneratedPluginRegistrant.m
+
+.generated/
+
+*.pbxuser
+*.mode1v3
+*.mode2v3
+*.perspectivev3
+
+!default.pbxuser
+!default.mode1v3
+!default.mode2v3
+!default.perspectivev3
+
+xcuserdata
+
+*.moved-aside
+
+*.pyc
+*sync/
+Icon?
+.tags*
+
+/Flutter/app.flx
+/Flutter/app.zip
+/Flutter/flutter_assets/
+/Flutter/App.framework
+/Flutter/Flutter.framework
+/Flutter/Generated.xcconfig
+/ServiceDefinitions.json
+
+Pods/
+.symlinks/

example/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>en</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>12.0</string>
+</dict>
+</plist>

example/ios/Flutter/Debug.xcconfig

+#include "Generated.xcconfig"

example/ios/Flutter/Release.xcconfig

+#include "Generated.xcconfig"

example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata

+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:">
+   </FileRef>
+</Workspace>

example/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>

example/ios/Runner.xcodeproj/project.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

+<?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>PreviewsEnabled</key>
+	<false/>
+</dict>
+</plist>

example/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1510"
+   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"
+      language = ""
+      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"
+      language = ""
+      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>

example/ios/Runner.xcworkspace/contents.xcworkspacedata

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

example/ios/Runner.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>

example/ios/Runner.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

+<?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>PreviewsEnabled</key>
+	<false/>
+</dict>
+</plist>

example/ios/Runner/AppDelegate.h

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

example/ios/Runner/AppDelegate.m

+#include "AppDelegate.h"
+#include "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

example/ios/Runner/AppDelegate.swift

+import UIKit
+import Flutter
+
+@UIApplicationMain
+@objc class AppDelegate: FlutterAppDelegate {
+  override func application(
+    _ application: UIApplication,
+    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
+  ) -> Bool {
+    GeneratedPluginRegistrant.register(with: self)
+    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
+  }
+}

example/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"
+    },
+    {
+      "size" : "1024x1024",
+      "idiom" : "ios-marketing",
+      "filename" : "Icon-App-1024x1024@1x.png",
+      "scale" : "1x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

example/ios/Runner/Assets.xcassets/LaunchImage.imageset/Contents.json

+{
+  "images" : [
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage.png",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@3x.png",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

example/ios/Runner/Assets.xcassets/LaunchImage.imageset/README.md

+# Launch Screen Assets
+
+You can customize the launch screen with your own desired assets by replacing the image files in this directory.
+
+You can also do it by opening your Flutter project's Xcode project with `open ios/Runner.xcworkspace`, selecting `Runner/Assets.xcassets` in the Project Navigator and dropping in the desired images.
\ No newline at end of file

example/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="12121" systemVersion="16G29" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12089"/>
+    </dependencies>
+    <scenes>
+        <!--View Controller-->
+        <scene sceneID="EHf-IW-A2E">
+            <objects>
+                <viewController id="01J-lp-oVM" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="Ydg-fD-yQy"/>
+                        <viewControllerLayoutGuide type="bottom" id="xbc-2k-c8Z"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <subviews>
+                            <imageView opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" image="LaunchImage" translatesAutoresizingMaskIntoConstraints="NO" id="YRO-k0-Ey4">
+                            </imageView>
+                        </subviews>
+                        <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+                        <constraints>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="1a2-6s-vTC"/>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerY" secondItem="Ze5-6b-2t3" secondAttribute="centerY" id="4X2-HB-R7a"/>
+                        </constraints>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="53" y="375"/>
+        </scene>
+    </scenes>
+    <resources>
+        <image name="LaunchImage" width="168" height="185"/>
+    </resources>
+</document>

example/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>

example/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>en</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>flutter_picker_example</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>$(FLUTTER_BUILD_NAME)</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>$(FLUTTER_BUILD_NUMBER)</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/>
+	<key>CADisableMinimumFrameDurationOnPhone</key>
+	<true/>
+	<key>UIApplicationSupportsIndirectInputEvents</key>
+	<true/>
+</dict>
+</plist>

example/ios/Runner/Runner-Bridging-Header.h

+#import "GeneratedPluginRegistrant.h"

example/ios/Runner/main.m

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

example/lib/picker_data.dart

+const PickerData = '''
+[
+    {
+        "a": [
+            {
+                "a1": [
+                    1,
+                    2,
+                    3,
+                    4
+                ]
+            },
+            {
+                "a2": [
+                    5,
+                    6,
+                    7,
+                    8,
+                    555,
+                    666,
+                    999
+                ]
+            },
+            {
+                "a3": [
+                    9,
+                    10,
+                    11,
+                    12
+                ]
+            }
+        ]
+    },
+    {
+        "b": [
+            {
+                "b1": [
+                    11,
+                    22,
+                    33,
+                    44
+                ]
+            },
+            {
+                "b2": [
+                    55,
+                    66,
+                    77,
+                    88,
+                    99,
+                    1010,
+                    1111,
+                    1212,
+                    1313,
+                    1414,
+                    1515,
+                    1616
+                ]
+            },
+            {
+                "b3": [
+                    1010,
+                    1111,
+                    1212,
+                    1313,
+                    1414,
+                    1515,
+                    1616
+                ]
+            }
+        ]
+    },
+    {
+        "c": [
+            {
+                "c1": [
+                    "a",
+                    "b",
+                    "c"
+                ]
+            },
+            {
+                "c2": [
+                    "aa",
+                    "bb",
+                    "cc"
+                ]
+            },
+            {
+                "c3": [
+                    "aaa",
+                    "bbb",
+                    "ccc"
+                ]
+            },
+            {
+                "c4": [
+                    "a1",
+                    "b1",
+                    "c1",
+                    "d1"
+                ]
+            }
+        ]
+    }
+]
+    ''';
+
+const PickerData2 = '''
+[
+    [
+        1,
+        2,
+        3,
+        4
+    ],
+    [
+        11,
+        22,
+        33,
+        44
+    ],
+    [
+        "aaa",
+        "bbb",
+        "ccc"
+    ]
+]
+    ''';
\ No newline at end of file

example/lib/picker_test.dart

+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+class RawPickerTest extends StatefulWidget {
+  const RawPickerTest({Key? key}) : super(key: key);
+
+  @override
+  State<RawPickerTest> createState() => _RawPickerTestState();
+}
+
+class _RawPickerTestState extends State<RawPickerTest> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: Text('Test Raw Picker')),
+      body: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          SizedBox(height: 50),
+          SizedBox(
+            height: 320,
+            child: Row(
+              children: [
+                Expanded(child: _buildCupertinoPicker(context, 0, 20, ValueKey(0))),
+                Expanded(child: _buildCupertinoPicker(context, 1, 120, ValueKey(1))),
+                Expanded(child: _buildCupertinoPicker(context, 2, 50, ValueKey(2))),
+              ],
+            ),
+          )
+        ],
+      ),
+    );
+  }
+
+  Widget _buildCupertinoPicker(BuildContext context,
+      int i, int _length, Key? key) {
+    return CupertinoPicker.builder(
+      key: key,
+      scrollController: FixedExtentScrollController(),
+      itemExtent: 42,
+      selectionOverlay: const CupertinoPickerDefaultSelectionOverlay(),
+      childCount: _length,
+      itemBuilder: (context, index) {
+        return Text("$i.$index");
+      },
+      onSelectedItemChanged: (int _index) {
+        if (_length <= 0) return;
+        var index = _index % _length;
+        print("onSelectedItemChanged. col: $i, row: $index");
+      },
+    );
+  }
+}

example/pubspec.yaml

+name: flutter_picker_example
+description: Demonstrates how to use the flutter_picker plugin.
+
+# The following defines the version and build number for your application.
+# A version number is three numbers separated by dots, like 1.2.43
+# followed by an optional build number separated by a +.
+# Both the version and the builder number may be overridden in flutter
+# build by specifying --build-name and --build-number, respectively.
+# Read more about versioning at semver.org.
+version: 1.0.0+1
+
+environment:
+  sdk: '>=2.12.0 <3.0.0'
+
+dependencies:
+  flutter:
+    sdk: flutter
+
+  flutter_localizations:
+    sdk: flutter
+
+  # intl: 0.18.0
+
+  # The following adds the Cupertino Icons font to your application.
+  # Use with the CupertinoIcons class for iOS style icons.
+  cupertino_icons: ^1.0.5
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+
+  flutter_picker:
+    path: ../
+
+# For information on the generic Dart part of this file, see the
+# following page: https://www.dartlang.org/tools/pub/pubspec
+
+# The following section is specific to Flutter.
+flutter:
+
+  # The following line ensures that the Material Icons font is
+  # included with your application, so that you can use the icons in
+  # the material Icons class.
+  uses-material-design: true
+
+  # To add assets to your application, add an assets section, like this:
+  # assets:
+  #  - images/a_dot_burr.jpeg
+  #  - images/a_dot_ham.jpeg
+
+  # An image asset can refer to one or more resolution-specific "variants", see
+  # https://flutter.io/assets-and-images/#resolution-aware.
+
+  # For details regarding adding assets from package dependencies, see
+  # https://flutter.io/assets-and-images/#from-packages
+
+  # To add custom fonts to your application, add a fonts section here,
+  # in this "flutter" section. Each entry in this list should have a
+  # "family" key with the font family name, and a "fonts" key with a
+  # list giving the asset and other descriptors for the font. For
+  # example:
+  # fonts:
+  #   - family: Schyler
+  #     fonts:
+  #       - asset: fonts/Schyler-Regular.ttf
+  #       - asset: fonts/Schyler-Italic.ttf
+  #         style: italic
+  #   - family: Trajan Pro
+  #     fonts:
+  #       - asset: fonts/TrajanPro.ttf
+  #       - asset: fonts/TrajanPro_Bold.ttf
+  #         weight: 700
+  #
+  # For details regarding fonts from package dependencies,
+  # see https://flutter.io/custom-fonts/#from-packages

example/web/index.html

+<!DOCTYPE html>
+<html>
+<head>
+  <!--
+    If you are serving your web app in a path other than the root, change the
+    href value below to reflect the base path you are serving from.
+
+    The path provided below has to start and end with a slash "/" in order for
+    it to work correctly.
+
+    For more details:
+    * https://developer.mozilla.org/en-US/docs/Web/HTML/Element/base
+
+    This is a placeholder for base href that will be replaced by the value of
+    the `--base-href` argument provided to `flutter build`.
+  -->
+  <base href="$FLUTTER_BASE_HREF">
+
+  <meta charset="UTF-8">
+  <meta content="IE=Edge" http-equiv="X-UA-Compatible">
+  <meta name="description" content="A new Flutter project.">
+
+  <!-- iOS meta tags & icons -->
+  <meta name="apple-mobile-web-app-capable" content="yes">
+  <meta name="apple-mobile-web-app-status-bar-style" content="black">
+  <meta name="apple-mobile-web-app-title" content="example">
+  <link rel="apple-touch-icon" href="icons/Icon-192.png">
+
+  <!-- Favicon -->
+  <link rel="icon" type="image/png" href="favicon.png"/>
+
+  <title>example</title>
+  <link rel="manifest" href="manifest.json">
+
+  <script>
+    // The value below is injected by flutter build, do not touch.
+    var serviceWorkerVersion = null;
+  </script>
+  <!-- This script adds the flutter initialization JS code -->
+  <script src="flutter.js" defer></script>
+</head>
+<body>
+  <script>
+    window.addEventListener('load', function(ev) {
+      // Download main.dart.js
+      _flutter.loader.loadEntrypoint({
+        serviceWorker: {
+          serviceWorkerVersion: serviceWorkerVersion,
+        }
+      }).then(function(engineInitializer) {
+        return engineInitializer.initializeEngine();
+      }).then(function(appRunner) {
+        return appRunner.runApp();
+      });
+    });
+  </script>
+</body>
+</html>

example/web/manifest.json

+{
+    "name": "example",
+    "short_name": "example",
+    "start_url": ".",
+    "display": "standalone",
+    "background_color": "#0175C2",
+    "theme_color": "#0175C2",
+    "description": "A new Flutter project.",
+    "orientation": "portrait-primary",
+    "prefer_related_applications": false,
+    "icons": [
+        {
+            "src": "icons/Icon-192.png",
+            "sizes": "192x192",
+            "type": "image/png"
+        },
+        {
+            "src": "icons/Icon-512.png",
+            "sizes": "512x512",
+            "type": "image/png"
+        },
+        {
+            "src": "icons/Icon-maskable-192.png",
+            "sizes": "192x192",
+            "type": "image/png",
+            "purpose": "maskable"
+        },
+        {
+            "src": "icons/Icon-maskable-512.png",
+            "sizes": "512x512",
+            "type": "image/png",
+            "purpose": "maskable"
+        }
+    ]
+}

example/windows/.gitignore

+flutter/ephemeral/
+
+# Visual Studio user-specific files.
+*.suo
+*.user
+*.userosscache
+*.sln.docstates
+
+# Visual Studio build-related files.
+x64/
+x86/
+
+# Visual Studio cache files
+# files ending in .cache can be ignored
+*.[Cc]ache
+# but keep track of directories ending in .cache
+!*.[Cc]ache/

example/windows/CMakeLists.txt

+cmake_minimum_required(VERSION 3.15)
+project(example LANGUAGES CXX)
+
+set(BINARY_NAME "example")
+
+cmake_policy(SET CMP0063 NEW)
+
+set(CMAKE_INSTALL_RPATH "$ORIGIN/lib")
+
+# Configure build options.
+get_property(IS_MULTICONFIG GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
+if(IS_MULTICONFIG)
+  set(CMAKE_CONFIGURATION_TYPES "Debug;Profile;Release"
+    CACHE STRING "" FORCE)
+else()
+  if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+    set(CMAKE_BUILD_TYPE "Debug" CACHE
+      STRING "Flutter build mode" FORCE)
+    set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
+      "Debug" "Profile" "Release")
+  endif()
+endif()
+
+set(CMAKE_EXE_LINKER_FLAGS_PROFILE "${CMAKE_EXE_LINKER_FLAGS_RELEASE}")
+set(CMAKE_SHARED_LINKER_FLAGS_PROFILE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE}")
+set(CMAKE_C_FLAGS_PROFILE "${CMAKE_C_FLAGS_RELEASE}")
+set(CMAKE_CXX_FLAGS_PROFILE "${CMAKE_CXX_FLAGS_RELEASE}")
+
+# Use Unicode for all projects.
+add_definitions(-DUNICODE -D_UNICODE)
+
+# Compilation settings that should be applied to most targets.
+function(APPLY_STANDARD_SETTINGS TARGET)
+  target_compile_features(${TARGET} PUBLIC cxx_std_17)
+  target_compile_options(${TARGET} PRIVATE /W4 /WX /wd"4100")
+  target_compile_options(${TARGET} PRIVATE /EHsc)
+  target_compile_definitions(${TARGET} PRIVATE "_HAS_EXCEPTIONS=0")
+  target_compile_definitions(${TARGET} PRIVATE "$<$<CONFIG:Debug>:_DEBUG>")
+endfunction()
+
+set(FLUTTER_MANAGED_DIR "${CMAKE_CURRENT_SOURCE_DIR}/flutter")
+
+# Flutter library and tool build rules.
+add_subdirectory(${FLUTTER_MANAGED_DIR})
+
+# Application build
+add_subdirectory("runner")
+
+# Generated plugin build rules, which manage building the plugins and adding
+# them to the application.
+include(flutter/generated_plugins.cmake)
+
+
+# === Installation ===
+# Support files are copied into place next to the executable, so that it can
+# run in place. This is done instead of making a separate bundle (as on Linux)
+# so that building and running from within Visual Studio will work.
+set(BUILD_BUNDLE_DIR "$<TARGET_FILE_DIR:${BINARY_NAME}>")
+# Make the "install" step default, as it's required to run.
+set(CMAKE_VS_INCLUDE_INSTALL_TO_DEFAULT_BUILD 1)
+if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
+  set(CMAKE_INSTALL_PREFIX "${BUILD_BUNDLE_DIR}" CACHE PATH "..." FORCE)
+endif()
+
+set(INSTALL_BUNDLE_DATA_DIR "${CMAKE_INSTALL_PREFIX}/data")
+set(INSTALL_BUNDLE_LIB_DIR "${CMAKE_INSTALL_PREFIX}")
+
+install(TARGETS ${BINARY_NAME} RUNTIME DESTINATION "${CMAKE_INSTALL_PREFIX}"
+  COMPONENT Runtime)
+
+install(FILES "${FLUTTER_ICU_DATA_FILE}" DESTINATION "${INSTALL_BUNDLE_DATA_DIR}"
+  COMPONENT Runtime)
+
+install(FILES "${FLUTTER_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
+  COMPONENT Runtime)
+
+if(PLUGIN_BUNDLED_LIBRARIES)
+  install(FILES "${PLUGIN_BUNDLED_LIBRARIES}"
+    DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
+    COMPONENT Runtime)
+endif()
+
+# Fully re-copy the assets directory on each build to avoid having stale files
+# from a previous install.
+set(FLUTTER_ASSET_DIR_NAME "flutter_assets")
+install(CODE "
+  file(REMOVE_RECURSE \"${INSTALL_BUNDLE_DATA_DIR}/${FLUTTER_ASSET_DIR_NAME}\")
+  " COMPONENT Runtime)
+install(DIRECTORY "${PROJECT_BUILD_DIR}/${FLUTTER_ASSET_DIR_NAME}"
+  DESTINATION "${INSTALL_BUNDLE_DATA_DIR}" COMPONENT Runtime)
+
+# Install the AOT library on non-Debug builds only.
+install(FILES "${AOT_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_DATA_DIR}"
+  CONFIGURATIONS Profile;Release
+  COMPONENT Runtime)

example/windows/flutter/CMakeLists.txt

+cmake_minimum_required(VERSION 3.15)
+
+set(EPHEMERAL_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ephemeral")
+
+# Configuration provided via flutter tool.
+include(${EPHEMERAL_DIR}/generated_config.cmake)
+
+# TODO: Move the rest of this into files in ephemeral. See
+# https://github.com/flutter/flutter/issues/57146.
+set(WRAPPER_ROOT "${EPHEMERAL_DIR}/cpp_client_wrapper")
+
+# === Flutter Library ===
+set(FLUTTER_LIBRARY "${EPHEMERAL_DIR}/flutter_windows.dll")
+
+# Published to parent scope for install step.
+set(FLUTTER_LIBRARY ${FLUTTER_LIBRARY} PARENT_SCOPE)
+set(FLUTTER_ICU_DATA_FILE "${EPHEMERAL_DIR}/icudtl.dat" PARENT_SCOPE)
+set(PROJECT_BUILD_DIR "${PROJECT_DIR}/build/" PARENT_SCOPE)
+set(AOT_LIBRARY "${PROJECT_DIR}/build/windows/app.so" PARENT_SCOPE)
+
+list(APPEND FLUTTER_LIBRARY_HEADERS
+  "flutter_export.h"
+  "flutter_windows.h"
+  "flutter_messenger.h"
+  "flutter_plugin_registrar.h"
+  "flutter_texture_registrar.h"
+)
+list(TRANSFORM FLUTTER_LIBRARY_HEADERS PREPEND "${EPHEMERAL_DIR}/")
+add_library(flutter INTERFACE)
+target_include_directories(flutter INTERFACE
+  "${EPHEMERAL_DIR}"
+)
+target_link_libraries(flutter INTERFACE "${FLUTTER_LIBRARY}.lib")
+add_dependencies(flutter flutter_assemble)
+
+# === Wrapper ===
+list(APPEND CPP_WRAPPER_SOURCES_CORE
+  "core_implementations.cc"
+  "standard_codec.cc"
+)
+list(TRANSFORM CPP_WRAPPER_SOURCES_CORE PREPEND "${WRAPPER_ROOT}/")
+list(APPEND CPP_WRAPPER_SOURCES_PLUGIN
+  "plugin_registrar.cc"
+)
+list(TRANSFORM CPP_WRAPPER_SOURCES_PLUGIN PREPEND "${WRAPPER_ROOT}/")
+list(APPEND CPP_WRAPPER_SOURCES_APP
+  "flutter_engine.cc"
+  "flutter_view_controller.cc"
+)
+list(TRANSFORM CPP_WRAPPER_SOURCES_APP PREPEND "${WRAPPER_ROOT}/")
+
+# Wrapper sources needed for a plugin.
+add_library(flutter_wrapper_plugin STATIC
+  ${CPP_WRAPPER_SOURCES_CORE}
+  ${CPP_WRAPPER_SOURCES_PLUGIN}
+)
+apply_standard_settings(flutter_wrapper_plugin)
+set_target_properties(flutter_wrapper_plugin PROPERTIES
+  POSITION_INDEPENDENT_CODE ON)
+set_target_properties(flutter_wrapper_plugin PROPERTIES
+  CXX_VISIBILITY_PRESET hidden)
+target_link_libraries(flutter_wrapper_plugin PUBLIC flutter)
+target_include_directories(flutter_wrapper_plugin PUBLIC
+  "${WRAPPER_ROOT}/include"
+)
+add_dependencies(flutter_wrapper_plugin flutter_assemble)
+
+# Wrapper sources needed for the runner.
+add_library(flutter_wrapper_app STATIC
+  ${CPP_WRAPPER_SOURCES_CORE}
+  ${CPP_WRAPPER_SOURCES_APP}
+)
+apply_standard_settings(flutter_wrapper_app)
+target_link_libraries(flutter_wrapper_app PUBLIC flutter)
+target_include_directories(flutter_wrapper_app PUBLIC
+  "${WRAPPER_ROOT}/include"
+)
+add_dependencies(flutter_wrapper_app flutter_assemble)
+
+# === Flutter tool backend ===
+# _phony_ is a non-existent file to force this command to run every time,
+# since currently there's no way to get a full input/output list from the
+# flutter tool.
+set(PHONY_OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/_phony_")
+set_source_files_properties("${PHONY_OUTPUT}" PROPERTIES SYMBOLIC TRUE)
+add_custom_command(
+  OUTPUT ${FLUTTER_LIBRARY} ${FLUTTER_LIBRARY_HEADERS}
+    ${CPP_WRAPPER_SOURCES_CORE} ${CPP_WRAPPER_SOURCES_PLUGIN}
+    ${CPP_WRAPPER_SOURCES_APP}
+    ${PHONY_OUTPUT}
+  COMMAND ${CMAKE_COMMAND} -E env
+    ${FLUTTER_TOOL_ENVIRONMENT}
+    "${FLUTTER_ROOT}/packages/flutter_tools/bin/tool_backend.bat"
+      windows-x64 $<CONFIG>
+  VERBATIM
+)
+add_custom_target(flutter_assemble DEPENDS
+  "${FLUTTER_LIBRARY}"
+  ${FLUTTER_LIBRARY_HEADERS}
+  ${CPP_WRAPPER_SOURCES_CORE}
+  ${CPP_WRAPPER_SOURCES_PLUGIN}
+  ${CPP_WRAPPER_SOURCES_APP}
+)

example/windows/flutter/generated_plugin_registrant.cc

+//
+//  Generated file. Do not edit.
+//
+
+// clang-format off
+
+#include "generated_plugin_registrant.h"
+
+
+void RegisterPlugins(flutter::PluginRegistry* registry) {
+}

example/windows/flutter/generated_plugin_registrant.h

+//
+//  Generated file. Do not edit.
+//
+
+// clang-format off
+
+#ifndef GENERATED_PLUGIN_REGISTRANT_
+#define GENERATED_PLUGIN_REGISTRANT_
+
+#include <flutter/plugin_registry.h>
+
+// Registers Flutter plugins.
+void RegisterPlugins(flutter::PluginRegistry* registry);
+
+#endif  // GENERATED_PLUGIN_REGISTRANT_

example/windows/flutter/generated_plugins.cmake

+#
+# Generated file, do not edit.
+#
+
+list(APPEND FLUTTER_PLUGIN_LIST
+)
+
+list(APPEND FLUTTER_FFI_PLUGIN_LIST
+)
+
+set(PLUGIN_BUNDLED_LIBRARIES)
+
+foreach(plugin ${FLUTTER_PLUGIN_LIST})
+  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${plugin}/windows plugins/${plugin})
+  target_link_libraries(${BINARY_NAME} PRIVATE ${plugin}_plugin)
+  list(APPEND PLUGIN_BUNDLED_LIBRARIES $<TARGET_FILE:${plugin}_plugin>)
+  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${plugin}_bundled_libraries})
+endforeach(plugin)
+
+foreach(ffi_plugin ${FLUTTER_FFI_PLUGIN_LIST})
+  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${ffi_plugin}/windows plugins/${ffi_plugin})
+  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${ffi_plugin}_bundled_libraries})
+endforeach(ffi_plugin)

example/windows/runner/CMakeLists.txt

+cmake_minimum_required(VERSION 3.15)
+project(runner LANGUAGES CXX)
+
+add_executable(${BINARY_NAME} WIN32
+  "flutter_window.cpp"
+  "main.cpp"
+  "run_loop.cpp"
+  "utils.cpp"
+  "win32_window.cpp"
+  "${FLUTTER_MANAGED_DIR}/generated_plugin_registrant.cc"
+  "Runner.rc"
+  "runner.exe.manifest"
+)
+apply_standard_settings(${BINARY_NAME})
+target_compile_definitions(${BINARY_NAME} PRIVATE "NOMINMAX")
+target_link_libraries(${BINARY_NAME} PRIVATE flutter flutter_wrapper_app)
+target_include_directories(${BINARY_NAME} PRIVATE "${CMAKE_SOURCE_DIR}")
+add_dependencies(${BINARY_NAME} flutter_assemble)

example/windows/runner/Runner.rc

+// Microsoft Visual C++ generated resource script.
+//
+#pragma code_page(65001)
+#include "resource.h"
+
+#define APSTUDIO_READONLY_SYMBOLS
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 2 resource.
+//
+#include "winres.h"
+
+/////////////////////////////////////////////////////////////////////////////
+#undef APSTUDIO_READONLY_SYMBOLS
+
+/////////////////////////////////////////////////////////////////////////////
+// English (United States) resources
+
+#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+
+#ifdef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// TEXTINCLUDE
+//
+
+1 TEXTINCLUDE
+BEGIN
+    "resource.h\0"
+END
+
+2 TEXTINCLUDE
+BEGIN
+    "#include ""winres.h""\r\n"
+    "\0"
+END
+
+3 TEXTINCLUDE
+BEGIN
+    "\r\n"
+    "\0"
+END
+
+#endif    // APSTUDIO_INVOKED
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Icon
+//
+
+// Icon with lowest ID value placed first to ensure application icon
+// remains consistent on all systems.
+IDI_APP_ICON            ICON                    "resources\\app_icon.ico"
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Version
+//
+
+#ifdef FLUTTER_BUILD_NUMBER
+#define VERSION_AS_NUMBER FLUTTER_BUILD_NUMBER
+#else
+#define VERSION_AS_NUMBER 1,0,0
+#endif
+
+#ifdef FLUTTER_BUILD_NAME
+#define VERSION_AS_STRING #FLUTTER_BUILD_NAME
+#else
+#define VERSION_AS_STRING "1.0.0"
+#endif
+
+VS_VERSION_INFO VERSIONINFO
+ FILEVERSION VERSION_AS_NUMBER
+ PRODUCTVERSION VERSION_AS_NUMBER
+ FILEFLAGSMASK VS_FFI_FILEFLAGSMASK
+#ifdef _DEBUG
+ FILEFLAGS VS_FF_DEBUG
+#else
+ FILEFLAGS 0x0L
+#endif
+ FILEOS VOS__WINDOWS32
+ FILETYPE VFT_APP
+ FILESUBTYPE 0x0L
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904e4"
+        BEGIN
+            VALUE "CompanyName", "com.yangyxd" "\0"
+            VALUE "FileDescription", "A new Flutter project." "\0"
+            VALUE "FileVersion", VERSION_AS_STRING "\0"
+            VALUE "InternalName", "example" "\0"
+            VALUE "LegalCopyright", "Copyright (C) 2021 com.yangyxd. All rights reserved." "\0"
+            VALUE "OriginalFilename", "example.exe" "\0"
+            VALUE "ProductName", "example" "\0"
+            VALUE "ProductVersion", VERSION_AS_STRING "\0"
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x409, 1252
+    END
+END
+
+#endif    // English (United States) resources
+/////////////////////////////////////////////////////////////////////////////
+
+
+
+#ifndef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 3 resource.
+//
+
+
+/////////////////////////////////////////////////////////////////////////////
+#endif    // not APSTUDIO_INVOKED

example/windows/runner/flutter_window.cpp

+#include "flutter_window.h"
+
+#include <optional>
+
+#include "flutter/generated_plugin_registrant.h"
+
+FlutterWindow::FlutterWindow(RunLoop* run_loop,
+                             const flutter::DartProject& project)
+    : run_loop_(run_loop), project_(project) {}
+
+FlutterWindow::~FlutterWindow() {}
+
+bool FlutterWindow::OnCreate() {
+  if (!Win32Window::OnCreate()) {
+    return false;
+  }
+
+  RECT frame = GetClientArea();
+
+  // The size here must match the window dimensions to avoid unnecessary surface
+  // creation / destruction in the startup path.
+  flutter_controller_ = std::make_unique<flutter::FlutterViewController>(
+      frame.right - frame.left, frame.bottom - frame.top, project_);
+  // Ensure that basic setup of the controller was successful.
+  if (!flutter_controller_->engine() || !flutter_controller_->view()) {
+    return false;
+  }
+  RegisterPlugins(flutter_controller_->engine());
+  run_loop_->RegisterFlutterInstance(flutter_controller_->engine());
+  SetChildContent(flutter_controller_->view()->GetNativeWindow());
+  return true;
+}
+
+void FlutterWindow::OnDestroy() {
+  if (flutter_controller_) {
+    run_loop_->UnregisterFlutterInstance(flutter_controller_->engine());
+    flutter_controller_ = nullptr;
+  }
+
+  Win32Window::OnDestroy();
+}
+
+LRESULT
+FlutterWindow::MessageHandler(HWND hwnd, UINT const message,
+                              WPARAM const wparam,
+                              LPARAM const lparam) noexcept {
+  // Give Flutter, including plugins, an opporutunity to handle window messages.
+  if (flutter_controller_) {
+    std::optional<LRESULT> result =
+        flutter_controller_->HandleTopLevelWindowProc(hwnd, message, wparam,
+                                                      lparam);
+    if (result) {
+      return *result;
+    }
+  }
+
+  switch (message) {
+    case WM_FONTCHANGE:
+      flutter_controller_->engine()->ReloadSystemFonts();
+      break;
+  }
+
+  return Win32Window::MessageHandler(hwnd, message, wparam, lparam);
+}

example/windows/runner/flutter_window.h

+#ifndef RUNNER_FLUTTER_WINDOW_H_
+#define RUNNER_FLUTTER_WINDOW_H_
+
+#include <flutter/dart_project.h>
+#include <flutter/flutter_view_controller.h>
+
+#include <memory>
+
+#include "run_loop.h"
+#include "win32_window.h"
+
+// A window that does nothing but host a Flutter view.
+class FlutterWindow : public Win32Window {
+ public:
+  // Creates a new FlutterWindow driven by the |run_loop|, hosting a
+  // Flutter view running |project|.
+  explicit FlutterWindow(RunLoop* run_loop,
+                         const flutter::DartProject& project);
+  virtual ~FlutterWindow();
+
+ protected:
+  // Win32Window:
+  bool OnCreate() override;
+  void OnDestroy() override;
+  LRESULT MessageHandler(HWND window, UINT const message, WPARAM const wparam,
+                         LPARAM const lparam) noexcept override;
+
+ private:
+  // The run loop driving events for this window.
+  RunLoop* run_loop_;
+
+  // The project to run.
+  flutter::DartProject project_;
+
+  // The Flutter instance hosted by this window.
+  std::unique_ptr<flutter::FlutterViewController> flutter_controller_;
+};
+
+#endif  // RUNNER_FLUTTER_WINDOW_H_

example/windows/runner/main.cpp

+#include <flutter/dart_project.h>
+#include <flutter/flutter_view_controller.h>
+#include <windows.h>
+
+#include "flutter_window.h"
+#include "run_loop.h"
+#include "utils.h"
+
+int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
+                      _In_ wchar_t *command_line, _In_ int show_command) {
+  // Attach to console when present (e.g., 'flutter run') or create a
+  // new console when running with a debugger.
+  if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {
+    CreateAndAttachConsole();
+  }
+
+  // Initialize COM, so that it is available for use in the library and/or
+  // plugins.
+  ::CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);
+
+  RunLoop run_loop;
+
+  flutter::DartProject project(L"data");
+
+  std::vector<std::string> command_line_arguments =
+      GetCommandLineArguments();
+
+  project.set_dart_entrypoint_arguments(std::move(command_line_arguments));
+
+  FlutterWindow window(&run_loop, project);
+  Win32Window::Point origin(10, 10);
+  Win32Window::Size size(1280, 720);
+  if (!window.CreateAndShow(L"example", origin, size)) {
+    return EXIT_FAILURE;
+  }
+  window.SetQuitOnClose(true);
+
+  run_loop.Run();
+
+  ::CoUninitialize();
+  return EXIT_SUCCESS;
+}

example/windows/runner/resource.h

+//{{NO_DEPENDENCIES}}
+// Microsoft Visual C++ generated include file.
+// Used by Runner.rc
+//
+#define IDI_APP_ICON                    101
+
+// Next default values for new objects
+//
+#ifdef APSTUDIO_INVOKED
+#ifndef APSTUDIO_READONLY_SYMBOLS
+#define _APS_NEXT_RESOURCE_VALUE        102
+#define _APS_NEXT_COMMAND_VALUE         40001
+#define _APS_NEXT_CONTROL_VALUE         1001
+#define _APS_NEXT_SYMED_VALUE           101
+#endif
+#endif

example/windows/runner/run_loop.cpp

+#include "run_loop.h"
+
+#include <windows.h>
+
+#include <algorithm>
+
+RunLoop::RunLoop() {}
+
+RunLoop::~RunLoop() {}
+
+void RunLoop::Run() {
+  bool keep_running = true;
+  TimePoint next_flutter_event_time = TimePoint::clock::now();
+  while (keep_running) {
+    std::chrono::nanoseconds wait_duration =
+        std::max(std::chrono::nanoseconds(0),
+                 next_flutter_event_time - TimePoint::clock::now());
+    ::MsgWaitForMultipleObjects(
+        0, nullptr, FALSE, static_cast<DWORD>(wait_duration.count() / 1000),
+        QS_ALLINPUT);
+    bool processed_events = false;
+    MSG message;
+    // All pending Windows messages must be processed; MsgWaitForMultipleObjects
+    // won't return again for items left in the queue after PeekMessage.
+    while (::PeekMessage(&message, nullptr, 0, 0, PM_REMOVE)) {
+      processed_events = true;
+      if (message.message == WM_QUIT) {
+        keep_running = false;
+        break;
+      }
+      ::TranslateMessage(&message);
+      ::DispatchMessage(&message);
+      // Allow Flutter to process messages each time a Windows message is
+      // processed, to prevent starvation.
+      next_flutter_event_time =
+          std::min(next_flutter_event_time, ProcessFlutterMessages());
+    }
+    // If the PeekMessage loop didn't run, process Flutter messages.
+    if (!processed_events) {
+      next_flutter_event_time =
+          std::min(next_flutter_event_time, ProcessFlutterMessages());
+    }
+  }
+}
+
+void RunLoop::RegisterFlutterInstance(
+    flutter::FlutterEngine* flutter_instance) {
+  flutter_instances_.insert(flutter_instance);
+}
+
+void RunLoop::UnregisterFlutterInstance(
+    flutter::FlutterEngine* flutter_instance) {
+  flutter_instances_.erase(flutter_instance);
+}
+
+RunLoop::TimePoint RunLoop::ProcessFlutterMessages() {
+  TimePoint next_event_time = TimePoint::max();
+  for (auto instance : flutter_instances_) {
+    std::chrono::nanoseconds wait_duration = instance->ProcessMessages();
+    if (wait_duration != std::chrono::nanoseconds::max()) {
+      next_event_time =
+          std::min(next_event_time, TimePoint::clock::now() + wait_duration);
+    }
+  }
+  return next_event_time;
+}

example/windows/runner/run_loop.h

+#ifndef RUNNER_RUN_LOOP_H_
+#define RUNNER_RUN_LOOP_H_
+
+#include <flutter/flutter_engine.h>
+
+#include <chrono>
+#include <set>
+
+// A runloop that will service events for Flutter instances as well
+// as native messages.
+class RunLoop {
+ public:
+  RunLoop();
+  ~RunLoop();
+
+  // Prevent copying
+  RunLoop(RunLoop const&) = delete;
+  RunLoop& operator=(RunLoop const&) = delete;
+
+  // Runs the run loop until the application quits.
+  void Run();
+
+  // Registers the given Flutter instance for event servicing.
+  void RegisterFlutterInstance(
+      flutter::FlutterEngine* flutter_instance);
+
+  // Unregisters the given Flutter instance from event servicing.
+  void UnregisterFlutterInstance(
+      flutter::FlutterEngine* flutter_instance);
+
+ private:
+  using TimePoint = std::chrono::steady_clock::time_point;
+
+  // Processes all currently pending messages for registered Flutter instances.
+  TimePoint ProcessFlutterMessages();
+
+  std::set<flutter::FlutterEngine*> flutter_instances_;
+};
+
+#endif  // RUNNER_RUN_LOOP_H_

example/windows/runner/runner.exe.manifest

+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+  <application xmlns="urn:schemas-microsoft-com:asm.v3">
+    <windowsSettings>
+      <dpiAwareness xmlns="http://schemas.microsoft.com/SMI/2016/WindowsSettings">PerMonitorV2</dpiAwareness>
+    </windowsSettings>
+  </application>
+  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+    <application>
+      <!-- Windows 10 -->
+      <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}"/>
+      <!-- Windows 8.1 -->
+      <supportedOS Id="{1f676c76-80e1-4239-95bb-83d0f6d0da78}"/>
+      <!-- Windows 8 -->
+      <supportedOS Id="{4a2f28e3-53b9-4441-ba9c-d69d4a4a6e38}"/>
+      <!-- Windows 7 -->
+      <supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}"/>
+    </application>
+  </compatibility>
+</assembly>

example/windows/runner/utils.cpp

+#include "utils.h"
+
+#include <flutter_windows.h>
+#include <io.h>
+#include <stdio.h>
+#include <windows.h>
+
+#include <iostream>
+
+void CreateAndAttachConsole() {
+  if (::AllocConsole()) {
+    FILE *unused;
+    if (freopen_s(&unused, "CONOUT$", "w", stdout)) {
+      _dup2(_fileno(stdout), 1);
+    }
+    if (freopen_s(&unused, "CONOUT$", "w", stderr)) {
+      _dup2(_fileno(stdout), 2);
+    }
+    std::ios::sync_with_stdio();
+    FlutterDesktopResyncOutputStreams();
+  }
+}
+
+std::vector<std::string> GetCommandLineArguments() {
+  // Convert the UTF-16 command line arguments to UTF-8 for the Engine to use.
+  int argc;
+  wchar_t** argv = ::CommandLineToArgvW(::GetCommandLineW(), &argc);
+  if (argv == nullptr) {
+    return std::vector<std::string>();
+  }
+
+  std::vector<std::string> command_line_arguments;
+
+  // Skip the first argument as it's the binary name.
+  for (int i = 1; i < argc; i++) {
+    command_line_arguments.push_back(Utf8FromUtf16(argv[i]));
+  }
+
+  ::LocalFree(argv);
+
+  return command_line_arguments;
+}
+
+std::string Utf8FromUtf16(const wchar_t* utf16_string) {
+  if (utf16_string == nullptr) {
+    return std::string();
+  }
+  int target_length = ::WideCharToMultiByte(
+      CP_UTF8, WC_ERR_INVALID_CHARS, utf16_string,
+      -1, nullptr, 0, nullptr, nullptr);
+  if (target_length == 0) {
+    return std::string();
+  }
+  std::string utf8_string;
+  utf8_string.resize(target_length);
+  int converted_length = ::WideCharToMultiByte(
+      CP_UTF8, WC_ERR_INVALID_CHARS, utf16_string,
+      -1, utf8_string.data(),
+      target_length, nullptr, nullptr);
+  if (converted_length == 0) {
+    return std::string();
+  }
+  return utf8_string;
+}

example/windows/runner/utils.h

+#ifndef RUNNER_UTILS_H_
+#define RUNNER_UTILS_H_
+
+#include <string>
+#include <vector>
+
+// Creates a console for the process, and redirects stdout and stderr to
+// it for both the runner and the Flutter library.
+void CreateAndAttachConsole();
+
+// Takes a null-terminated wchar_t* encoded in UTF-16 and returns a std::string
+// encoded in UTF-8. Returns an empty std::string on failure.
+std::string Utf8FromUtf16(const wchar_t* utf16_string);
+
+// Gets the command line arguments passed in as a std::vector<std::string>,
+// encoded in UTF-8. Returns an empty std::vector<std::string> on failure.
+std::vector<std::string> GetCommandLineArguments();
+
+#endif  // RUNNER_UTILS_H_

example/windows/runner/win32_window.cpp

+#include "win32_window.h"
+
+#include <flutter_windows.h>
+
+#include "resource.h"
+
+namespace {
+
+constexpr const wchar_t kWindowClassName[] = L"FLUTTER_RUNNER_WIN32_WINDOW";
+
+// The number of Win32Window objects that currently exist.
+static int g_active_window_count = 0;
+
+using EnableNonClientDpiScaling = BOOL __stdcall(HWND hwnd);
+
+// Scale helper to convert logical scaler values to physical using passed in
+// scale factor
+int Scale(int source, double scale_factor) {
+  return static_cast<int>(source * scale_factor);
+}
+
+// Dynamically loads the |EnableNonClientDpiScaling| from the User32 module.
+// This API is only needed for PerMonitor V1 awareness mode.
+void EnableFullDpiSupportIfAvailable(HWND hwnd) {
+  HMODULE user32_module = LoadLibraryA("User32.dll");
+  if (!user32_module) {
+    return;
+  }
+  auto enable_non_client_dpi_scaling =
+      reinterpret_cast<EnableNonClientDpiScaling*>(
+          GetProcAddress(user32_module, "EnableNonClientDpiScaling"));
+  if (enable_non_client_dpi_scaling != nullptr) {
+    enable_non_client_dpi_scaling(hwnd);
+    FreeLibrary(user32_module);
+  }
+}
+
+}  // namespace
+
+// Manages the Win32Window's window class registration.
+class WindowClassRegistrar {
+ public:
+  ~WindowClassRegistrar() = default;
+
+  // Returns the singleton registar instance.
+  static WindowClassRegistrar* GetInstance() {
+    if (!instance_) {
+      instance_ = new WindowClassRegistrar();
+    }
+    return instance_;
+  }
+
+  // Returns the name of the window class, registering the class if it hasn't
+  // previously been registered.
+  const wchar_t* GetWindowClass();
+
+  // Unregisters the window class. Should only be called if there are no
+  // instances of the window.
+  void UnregisterWindowClass();
+
+ private:
+  WindowClassRegistrar() = default;
+
+  static WindowClassRegistrar* instance_;
+
+  bool class_registered_ = false;
+};
+
+WindowClassRegistrar* WindowClassRegistrar::instance_ = nullptr;
+
+const wchar_t* WindowClassRegistrar::GetWindowClass() {
+  if (!class_registered_) {
+    WNDCLASS window_class{};
+    window_class.hCursor = LoadCursor(nullptr, IDC_ARROW);
+    window_class.lpszClassName = kWindowClassName;
+    window_class.style = CS_HREDRAW | CS_VREDRAW;
+    window_class.cbClsExtra = 0;
+    window_class.cbWndExtra = 0;
+    window_class.hInstance = GetModuleHandle(nullptr);
+    window_class.hIcon =
+        LoadIcon(window_class.hInstance, MAKEINTRESOURCE(IDI_APP_ICON));
+    window_class.hbrBackground = 0;
+    window_class.lpszMenuName = nullptr;
+    window_class.lpfnWndProc = Win32Window::WndProc;
+    RegisterClass(&window_class);
+    class_registered_ = true;
+  }
+  return kWindowClassName;
+}
+
+void WindowClassRegistrar::UnregisterWindowClass() {
+  UnregisterClass(kWindowClassName, nullptr);
+  class_registered_ = false;
+}
+
+Win32Window::Win32Window() {
+  ++g_active_window_count;
+}
+
+Win32Window::~Win32Window() {
+  --g_active_window_count;
+  Destroy();
+}
+
+bool Win32Window::CreateAndShow(const std::wstring& title,
+                                const Point& origin,
+                                const Size& size) {
+  Destroy();
+
+  const wchar_t* window_class =
+      WindowClassRegistrar::GetInstance()->GetWindowClass();
+
+  const POINT target_point = {static_cast<LONG>(origin.x),
+                              static_cast<LONG>(origin.y)};
+  HMONITOR monitor = MonitorFromPoint(target_point, MONITOR_DEFAULTTONEAREST);
+  UINT dpi = FlutterDesktopGetDpiForMonitor(monitor);
+  double scale_factor = dpi / 96.0;
+
+  HWND window = CreateWindow(
+      window_class, title.c_str(), WS_OVERLAPPEDWINDOW | WS_VISIBLE,
+      Scale(origin.x, scale_factor), Scale(origin.y, scale_factor),
+      Scale(size.width, scale_factor), Scale(size.height, scale_factor),
+      nullptr, nullptr, GetModuleHandle(nullptr), this);
+
+  if (!window) {
+    return false;
+  }
+
+  return OnCreate();
+}
+
+// static
+LRESULT CALLBACK Win32Window::WndProc(HWND const window,
+                                      UINT const message,
+                                      WPARAM const wparam,
+                                      LPARAM const lparam) noexcept {
+  if (message == WM_NCCREATE) {
+    auto window_struct = reinterpret_cast<CREATESTRUCT*>(lparam);
+    SetWindowLongPtr(window, GWLP_USERDATA,
+                     reinterpret_cast<LONG_PTR>(window_struct->lpCreateParams));
+
+    auto that = static_cast<Win32Window*>(window_struct->lpCreateParams);
+    EnableFullDpiSupportIfAvailable(window);
+    that->window_handle_ = window;
+  } else if (Win32Window* that = GetThisFromHandle(window)) {
+    return that->MessageHandler(window, message, wparam, lparam);
+  }
+
+  return DefWindowProc(window, message, wparam, lparam);
+}
+
+LRESULT
+Win32Window::MessageHandler(HWND hwnd,
+                            UINT const message,
+                            WPARAM const wparam,
+                            LPARAM const lparam) noexcept {
+  switch (message) {
+    case WM_DESTROY:
+      window_handle_ = nullptr;
+      Destroy();
+      if (quit_on_close_) {
+        PostQuitMessage(0);
+      }
+      return 0;
+
+    case WM_DPICHANGED: {
+      auto newRectSize = reinterpret_cast<RECT*>(lparam);
+      LONG newWidth = newRectSize->right - newRectSize->left;
+      LONG newHeight = newRectSize->bottom - newRectSize->top;
+
+      SetWindowPos(hwnd, nullptr, newRectSize->left, newRectSize->top, newWidth,
+                   newHeight, SWP_NOZORDER | SWP_NOACTIVATE);
+
+      return 0;
+    }
+    case WM_SIZE: {
+      RECT rect = GetClientArea();
+      if (child_content_ != nullptr) {
+        // Size and position the child window.
+        MoveWindow(child_content_, rect.left, rect.top, rect.right - rect.left,
+                   rect.bottom - rect.top, TRUE);
+      }
+      return 0;
+    }
+
+    case WM_ACTIVATE:
+      if (child_content_ != nullptr) {
+        SetFocus(child_content_);
+      }
+      return 0;
+  }
+
+  return DefWindowProc(window_handle_, message, wparam, lparam);
+}
+
+void Win32Window::Destroy() {
+  OnDestroy();
+
+  if (window_handle_) {
+    DestroyWindow(window_handle_);
+    window_handle_ = nullptr;
+  }
+  if (g_active_window_count == 0) {
+    WindowClassRegistrar::GetInstance()->UnregisterWindowClass();
+  }
+}
+
+Win32Window* Win32Window::GetThisFromHandle(HWND const window) noexcept {
+  return reinterpret_cast<Win32Window*>(
+      GetWindowLongPtr(window, GWLP_USERDATA));
+}
+
+void Win32Window::SetChildContent(HWND content) {
+  child_content_ = content;
+  SetParent(content, window_handle_);
+  RECT frame = GetClientArea();
+
+  MoveWindow(content, frame.left, frame.top, frame.right - frame.left,
+             frame.bottom - frame.top, true);
+
+  SetFocus(child_content_);
+}
+
+RECT Win32Window::GetClientArea() {
+  RECT frame;
+  GetClientRect(window_handle_, &frame);
+  return frame;
+}
+
+HWND Win32Window::GetHandle() {
+  return window_handle_;
+}
+
+void Win32Window::SetQuitOnClose(bool quit_on_close) {
+  quit_on_close_ = quit_on_close;
+}
+
+bool Win32Window::OnCreate() {
+  // No-op; provided for subclasses.
+  return true;
+}
+
+void Win32Window::OnDestroy() {
+  // No-op; provided for subclasses.
+}

example/windows/runner/win32_window.h

+#ifndef RUNNER_WIN32_WINDOW_H_
+#define RUNNER_WIN32_WINDOW_H_
+
+#include <windows.h>
+
+#include <functional>
+#include <memory>
+#include <string>
+
+// A class abstraction for a high DPI-aware Win32 Window. Intended to be
+// inherited from by classes that wish to specialize with custom
+// rendering and input handling
+class Win32Window {
+ public:
+  struct Point {
+    unsigned int x;
+    unsigned int y;
+    Point(unsigned int x, unsigned int y) : x(x), y(y) {}
+  };
+
+  struct Size {
+    unsigned int width;
+    unsigned int height;
+    Size(unsigned int width, unsigned int height)
+        : width(width), height(height) {}
+  };
+
+  Win32Window();
+  virtual ~Win32Window();
+
+  // Creates and shows a win32 window with |title| and position and size using
+  // |origin| and |size|. New windows are created on the default monitor. Window
+  // sizes are specified to the OS in physical pixels, hence to ensure a
+  // consistent size to will treat the width height passed in to this function
+  // as logical pixels and scale to appropriate for the default monitor. Returns
+  // true if the window was created successfully.
+  bool CreateAndShow(const std::wstring& title,
+                     const Point& origin,
+                     const Size& size);
+
+  // Release OS resources associated with window.
+  void Destroy();
+
+  // Inserts |content| into the window tree.
+  void SetChildContent(HWND content);
+
+  // Returns the backing Window handle to enable clients to set icon and other
+  // window properties. Returns nullptr if the window has been destroyed.
+  HWND GetHandle();
+
+  // If true, closing this window will quit the application.
+  void SetQuitOnClose(bool quit_on_close);
+
+  // Return a RECT representing the bounds of the current client area.
+  RECT GetClientArea();
+
+ protected:
+  // Processes and route salient window messages for mouse handling,
+  // size change and DPI. Delegates handling of these to member overloads that
+  // inheriting classes can handle.
+  virtual LRESULT MessageHandler(HWND window,
+                                 UINT const message,
+                                 WPARAM const wparam,
+                                 LPARAM const lparam) noexcept;
+
+  // Called when CreateAndShow is called, allowing subclass window-related
+  // setup. Subclasses should return false if setup fails.
+  virtual bool OnCreate();
+
+  // Called when Destroy is called.
+  virtual void OnDestroy();
+
+ private:
+  friend class WindowClassRegistrar;
+
+  // OS callback called by message pump. Handles the WM_NCCREATE message which
+  // is passed when the non-client area is being created and enables automatic
+  // non-client DPI scaling so that the non-client area automatically
+  // responsponds to changes in DPI. All other messages are handled by
+  // MessageHandler.
+  static LRESULT CALLBACK WndProc(HWND const window,
+                                  UINT const message,
+                                  WPARAM const wparam,
+                                  LPARAM const lparam) noexcept;
+
+  // Retrieves a class instance pointer for |window|
+  static Win32Window* GetThisFromHandle(HWND const window) noexcept;
+
+  bool quit_on_close_ = false;
+
+  // window handle for top level window.
+  HWND window_handle_ = nullptr;
+
+  // window handle for hosted content.
+  HWND child_content_ = nullptr;
+};
+
+#endif  // RUNNER_WIN32_WINDOW_H_