Update the examples/ README and associated fixes. (#9090)

This yak shave went as follows:

Fix https://github.com/flutter/flutter/issues/8795 by adding stocks to
the examples README.

Notice the layers entry in that README isn't quite right either.
Update that.

Check the layers/README file is worth pointing at.

Update the layers/README.

Let's run some of the layer tests to see if they still work.

Oops, need to update them to gradle.

Ok let's try running them again.

Oops, sector is broken.

Add a test for sector.

Fix sector. Find you need to add an assert to a const constructor.

Notice we need to turn const asserts on for the analyzer.

Notice the analysis_options files are out of sync with each other and
with the full list of lints.

Turn on the lints that should be on.

Fix the bugs that finds.

.analysis_options

@@ -21,6 +21,7 @@ analyzer:
   language:
     enableStrictCallChecks: true
     enableSuperMixins: true
+    enableAssertInitializer: true
   strong-mode:
     implicit-dynamic: false
   errors:
@@ -48,9 +49,9 @@ linter:
     # === error rules ===
     - avoid_empty_else
     - avoid_slow_async_io
-    # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153
     - cancel_subscriptions
     # - close_sinks # https://github.com/flutter/flutter/issues/5789
+    # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153
     - control_flow_in_finally
     - empty_statements
     - hash_and_equals
@@ -73,26 +74,29 @@ linter:
     - await_only_futures
     - camel_case_types
     # - constant_identifier_names # https://github.com/dart-lang/linter/issues/204
-    - control_flow_in_finally
+    - empty_catches
     - empty_constructor_bodies
     - implementation_imports
     - library_names
     - library_prefixes
     - non_constant_identifier_names
-    - one_member_abstracts
+    # - one_member_abstracts # too many false positives
     # - only_throw_errors # https://github.com/flutter/flutter/issues/5792
     # - overridden_fields
     - package_api_docs
     - package_prefixed_library_names
+    # - parameter_assignments # we do this commonly
+    # - prefer_final_fields # https://github.com/dart-lang/sdk/issues/29197
     - prefer_final_locals
     - prefer_is_not_empty
-    # - public_member_api_docs
+    # - public_member_api_docs # this is the only difference from .analysis_options_repo
     - slash_for_doc_comments
     - sort_constructors_first
     - sort_unnamed_constructors_first
     - super_goes_last
     # - type_annotate_public_apis # subset of always_specify_types
     - type_init_formals
+    # - unawaited_futures # https://github.com/flutter/flutter/issues/5793
     - unnecessary_brace_in_string_interp
     - unnecessary_getters_setters
 

.analysis_options_repo

@@ -22,13 +22,14 @@ analyzer:
   language:
     enableStrictCallChecks: true
     enableSuperMixins: true
+    enableAssertInitializer: true
   strong-mode:
     implicit-dynamic: false
   errors:
     # treat missing required parameters as a warning (not a hint)
     missing_required_param: warning
     # treat missing returns as a warning (not a hint)
-    missing_return: warning    
+    missing_return: warning
     # allow overriding fields (if they use super, ideally...)
     strong_mode_invalid_field_override: ignore
     # allow having TODOs in the code
@@ -45,9 +46,10 @@ linter:
 
     # === error rules ===
     - avoid_empty_else
-    # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153
+    - avoid_slow_async_io
     - cancel_subscriptions
     # - close_sinks # https://github.com/flutter/flutter/issues/5789
+    # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153
     - control_flow_in_finally
     - empty_statements
     - hash_and_equals
@@ -70,20 +72,22 @@ linter:
     - await_only_futures
     - camel_case_types
     # - constant_identifier_names # https://github.com/dart-lang/linter/issues/204
-    - control_flow_in_finally
+    - empty_catches
     - empty_constructor_bodies
     - implementation_imports
     - library_names
     - library_prefixes
     - non_constant_identifier_names
-    - one_member_abstracts
+    # - one_member_abstracts # too many false positives
     # - only_throw_errors # https://github.com/flutter/flutter/issues/5792
     # - overridden_fields
     - package_api_docs
     - package_prefixed_library_names
+    # - parameter_assignments # we do this commonly
+    # - prefer_final_fields # https://github.com/dart-lang/sdk/issues/29197
     - prefer_final_locals
     - prefer_is_not_empty
-    - public_member_api_docs
+    - public_member_api_docs # this is the only difference from .analysis_options
     - slash_for_doc_comments
     - sort_constructors_first
     - sort_unnamed_constructors_first

examples/README.md

@@ -10,8 +10,10 @@ the `flutter` tool.
 
 **Tip:** To see examples of how to use a specific Flutter framework class,
 copy and paste a URL with this format in your browser. Replace `foo` with the
-classname you are searching for (for example, here's the [query](https://github.com/flutter/flutter/search?q=path%3Aexamples+new+AppBar) for examples of
-the [`AppBar`](https://docs.flutter.io/flutter/material/AppBar-class.html) class).
+classname you are searching for (for example, here's the
+[query](https://github.com/flutter/flutter/search?q=path%3Aexamples+new+AppBar)
+for examples of the
+[`AppBar`](https://docs.flutter.io/flutter/material/AppBar-class.html) class).
 
 ```
 https://github.com/flutter/flutter/search?q=path%3Aexamples+new+foo
@@ -23,11 +25,12 @@ Available examples include:
   the text "hello, world."
 
 - **Flutter gallery** The [flutter gallery app](flutter_gallery) showcases
-  Flutter's implementation of [material design](https://material.google.com/).
+  Flutter's widgets, including its implementation of
+  [material design](https://material.google.com/).
 
 - **Platform Channel** The [platform channel app](platform_channel)
   demonstrates how to connect a Flutter app to platform-specific APIs. For
-  documentation, see https://flutter.io/platform-channels/ .
+  documentation, see <https://flutter.io/platform-channels/>.
 
 - **Platform Channel Swift** The [platform channel swift
   app](platform_channel_swift) is the same as [platform
@@ -38,6 +41,7 @@ Available examples include:
   embed Flutter within an iOS or Android app.
 
 - **Layers** The [layers vignettes](layers) show how to use the various layers
-  in the Flutter framework. There is no main.dart in this directory because each
-  file is a standalone example. To run a particular file, use
-  `flutter run -t filename.dart`.
+  in the Flutter framework. For details, see the [layers README](layers/README).
+
+- **Stocks** The [stocks](stocks) demo shows how one might structure
+  an application with several screens.

examples/layers/.gitignore

+.DS_Store
+.atom/
+.idea
+.packages
+.pub/
+build/
+ios/.generated/
+packages
+pubspec.lock
+.flutter-plugins

examples/layers/README.md

@@ -18,8 +18,11 @@ Flutter's layered architecture.
  * [*services/*](services/) These examples use services available in Flutter to
    interact with the host platform.
 
-To run each example, use the `-t` argument to the `flutter` tool:
+To run each example, specify the demo file on the `flutter run`
+command line, for example:
 
 ```
-flutter run -t widgets/spinning_square.dart
+flutter run raw/spinning_square.dart
+flutter run rendering/spinning_square.dart
+flutter run widgets/spinning_square.dart
 ```

examples/layers/android/.gitignore

+*.iml
+.gradle
+/local.properties
+/.idea/workspace.xml
+/.idea/libraries
+.DS_Store
+/build
+/captures
+
+/gradle
+/gradlew
+/gradlew.bat

examples/layers/android/AndroidManifest.xml

-<?xml version="1.0" encoding="utf-8"?>
-<!-- Copyright 2015 The Chromium Authors. All rights reserved.
-     Use of this source code is governed by a BSD-style license that can be
-     found in the LICENSE file.
- -->
-<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="io.flutter.examples.Layers" android:versionCode="1" android:versionName="0.0.1">
-
-    <uses-sdk android:minSdkVersion="14" android:targetSdkVersion="21" />
-    <uses-permission android:name="android.permission.INTERNET"/>
-
-    <application android:label="Flutter Layers" android:name="io.flutter.app.FlutterApplication">
-        <activity android:configChanges="orientation|keyboardHidden|keyboard|screenSize" android:hardwareAccelerated="true" android:launchMode="singleTop" android:name="io.flutter.app.FlutterActivity" android:theme="@android:style/Theme.Black.NoTitleBar" android:windowSoftInputMode="adjustResize">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
-        </activity>
-    </application>
- </manifest>

examples/layers/android/app/build.gradle

+def localProperties = new Properties()
+def localPropertiesFile = rootProject.file('local.properties')
+if (localPropertiesFile.exists()) {
+    localPropertiesFile.withInputStream { stream ->
+        localProperties.load(stream)
+    }
+}
+
+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.")
+}
+
+apply plugin: 'com.android.application'
+apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+
+android {
+    compileSdkVersion 25
+    buildToolsVersion '25.0.2'
+
+    lintOptions {
+        disable 'InvalidPackage'
+    }
+
+    defaultConfig {
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+    }
+
+    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 {
+    androidTestCompile 'com.android.support:support-annotations:25.0.0'
+    androidTestCompile 'com.android.support.test:runner:0.5'
+    androidTestCompile 'com.android.support.test:rules:0.5'
+}

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

+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="io.flutter.examples.Layers"
+    android:versionCode="1"
+    android:versionName="0.0.1">
+
+    <uses-sdk android:minSdkVersion="16" android:targetSdkVersion="21" />
+
+    <!-- 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"/>
+
+    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
+         calls FlutterMain.startInitialization(this); in its onCreate method.
+         In most cases you can leave this as-is, but you if you want to provide
+         additional functionality it is fine to subclass or reimplement
+         FlutterApplication and put your custom class here. -->
+    <application android:name="io.flutter.app.FlutterApplication" android:label="Flutter Layers" android:icon="@mipmap/ic_launcher">
+        <activity android:name=".MainActivity"
+                  android:launchMode="singleTop"
+                  android:theme="@android:style/Theme.Black.NoTitleBar"
+                  android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection"
+                  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>
+    </application>
+</manifest>

examples/layers/android/app/src/main/java/io/flutter/examples/Layers/MainActivity.java

+package io.flutter.examples.Layers;
+
+import android.os.Bundle;
+import io.flutter.app.FlutterActivity;
+
+public class MainActivity extends FlutterActivity {
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+    }
+}
+

examples/layers/android/build.gradle

+buildscript {
+    repositories {
+        jcenter()
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:2.2.3'
+    }
+}
+
+allprojects {
+    repositories {
+        jcenter()
+    }
+}
+
+rootProject.buildDir = '../build'
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}
+
+task wrapper(type: Wrapper) {
+    gradleVersion = '2.14.1'
+}

examples/layers/android/gradle.properties

+org.gradle.jvmargs=-Xmx1536M

examples/layers/android/settings.gradle

+include ':app'
+
+def flutterProjectRoot = rootProject.projectDir.parentFile.toPath()
+
+def plugins = new Properties()
+def pluginsFile = new File(flutterProjectRoot.toFile(), '.flutter-plugins')
+if (pluginsFile.exists()) {
+    pluginsFile.withInputStream { stream -> plugins.load(stream) }
+}
+
+plugins.each { name, path ->
+    def pluginDirectory = flutterProjectRoot.resolve(path).resolve('android').toFile()
+    include ":$name"
+    project(":$name").projectDir = pluginDirectory
+}

examples/layers/ios/.gitignore

+.idea/
+.vagrant/
+.sconsign.dblite
+.svn/
+
+.DS_Store
+*.swp
+profile
+
+DerivedData/
+build/
+
+*.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/App.framework
+/Flutter/Flutter.framework
+/Flutter/Generated.xcconfig
+/ServiceDefinitions.json

examples/layers/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>UIRequiredDeviceCapabilities</key>
+  <array>
+    <string>arm64</string>
+  </array>
+  <key>MinimumOSVersion</key>
+  <string>8.0</string>
+</dict>
+</plist>

examples/layers/ios/Flutter/Debug.xcconfig

+#include "Generated.xcconfig"
+#include "Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"

examples/layers/ios/Flutter/Release.xcconfig

+#include "Generated.xcconfig"
+#include "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"

examples/layers/ios/Podfile

+# Uncomment this line to define a global platform for your project
+# platform :ios, '9.0'
+
+if ENV['FLUTTER_FRAMEWORK_DIR'] == nil
+  abort('Please set FLUTTER_FRAMEWORK_DIR to the directory containing Flutter.framework')
+end
+
+target 'Runner' do
+  use_frameworks!
+
+  # Pods for Runner
+
+  # Flutter Pods
+  pod 'Flutter', :path => ENV['FLUTTER_FRAMEWORK_DIR']
+
+  if File.exists? '../.flutter-plugins'
+    flutter_root = File.expand_path('..')
+    File.foreach('../.flutter-plugins') { |line|
+      plugin = line.split(pattern='=')
+      if plugin.length == 2
+        name = plugin[0].strip()
+        path = plugin[1].strip()
+        resolved_path = File.expand_path("#{path}/ios", flutter_root)
+        pod name, :path => resolved_path
+      else
+        puts "Invalid plugin specification: #{line}"
+      end
+    }
+  end
+end
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    target.build_configurations.each do |config|
+      config.build_settings['ENABLE_BITCODE'] = 'NO'
+    end
+  end
+end

examples/layers/ios/Podfile.lock

+PODFILE CHECKSUM: fe68fbd35e5bc75c5acdec41319edc0cdaebd038
+
+COCOAPODS: 1.0.1

examples/layers/ios/Pods/Manifest.lock

+PODFILE CHECKSUM: fe68fbd35e5bc75c5acdec41319edc0cdaebd038
+
+COCOAPODS: 1.0.1

examples/layers/ios/Pods/Pods.xcodeproj/xcshareddata/xcschemes/Pods-Runner.xcscheme

+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "0830"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "B0B211B0FA111CE20F29C3A6B3CED356"
+               BuildableName = "libPods-Runner.a"
+               BlueprintName = "Pods-Runner"
+               ReferencedContainer = "container:Pods.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+      <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">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "B0B211B0FA111CE20F29C3A6B3CED356"
+            BuildableName = "libPods-Runner.a"
+            BlueprintName = "Pods-Runner"
+            ReferencedContainer = "container:Pods.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "B0B211B0FA111CE20F29C3A6B3CED356"
+            BuildableName = "libPods-Runner.a"
+            BlueprintName = "Pods-Runner"
+            ReferencedContainer = "container:Pods.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner-acknowledgements.markdown

+# Acknowledgements
+This application makes use of the following third party libraries:
+Generated by CocoaPods - https://cocoapods.org

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner-acknowledgements.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>PreferenceSpecifiers</key>
+	<array>
+		<dict>
+			<key>FooterText</key>
+			<string>This application makes use of the following third party libraries:</string>
+			<key>Title</key>
+			<string>Acknowledgements</string>
+			<key>Type</key>
+			<string>PSGroupSpecifier</string>
+		</dict>
+		<dict>
+			<key>FooterText</key>
+			<string>Generated by CocoaPods - https://cocoapods.org</string>
+			<key>Title</key>
+			<string></string>
+			<key>Type</key>
+			<string>PSGroupSpecifier</string>
+		</dict>
+	</array>
+	<key>StringsTable</key>
+	<string>Acknowledgements</string>
+	<key>Title</key>
+	<string>Acknowledgements</string>
+</dict>
+</plist>

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner-dummy.m

+#import <Foundation/Foundation.h>
+@interface PodsDummy_Pods_Runner : NSObject
+@end
+@implementation PodsDummy_Pods_Runner
+@end

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner-frameworks.sh

+#!/bin/sh
+set -e
+
+echo "mkdir -p ${CONFIGURATION_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+mkdir -p "${CONFIGURATION_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+
+SWIFT_STDLIB_PATH="${DT_TOOLCHAIN_DIR}/usr/lib/swift/${PLATFORM_NAME}"
+
+install_framework()
+{
+  if [ -r "${BUILT_PRODUCTS_DIR}/$1" ]; then
+    local source="${BUILT_PRODUCTS_DIR}/$1"
+  elif [ -r "${BUILT_PRODUCTS_DIR}/$(basename "$1")" ]; then
+    local source="${BUILT_PRODUCTS_DIR}/$(basename "$1")"
+  elif [ -r "$1" ]; then
+    local source="$1"
+  fi
+
+  local destination="${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+
+  if [ -L "${source}" ]; then
+      echo "Symlinked..."
+      source="$(readlink "${source}")"
+  fi
+
+  # use filter instead of exclude so missing patterns dont' throw errors
+  echo "rsync -av --filter \"- CVS/\" --filter \"- .svn/\" --filter \"- .git/\" --filter \"- .hg/\" --filter \"- Headers\" --filter \"- PrivateHeaders\" --filter \"- Modules\" \"${source}\" \"${destination}\""
+  rsync -av --filter "- CVS/" --filter "- .svn/" --filter "- .git/" --filter "- .hg/" --filter "- Headers" --filter "- PrivateHeaders" --filter "- Modules" "${source}" "${destination}"
+
+  local basename
+  basename="$(basename -s .framework "$1")"
+  binary="${destination}/${basename}.framework/${basename}"
+  if ! [ -r "$binary" ]; then
+    binary="${destination}/${basename}"
+  fi
+
+  # Strip invalid architectures so "fat" simulator / device frameworks work on device
+  if [[ "$(file "$binary")" == *"dynamically linked shared library"* ]]; then
+    strip_invalid_archs "$binary"
+  fi
+
+  # Resign the code if required by the build settings to avoid unstable apps
+  code_sign_if_enabled "${destination}/$(basename "$1")"
+
+  # Embed linked Swift runtime libraries. No longer necessary as of Xcode 7.
+  if [ "${XCODE_VERSION_MAJOR}" -lt 7 ]; then
+    local swift_runtime_libs
+    swift_runtime_libs=$(xcrun otool -LX "$binary" | grep --color=never @rpath/libswift | sed -E s/@rpath\\/\(.+dylib\).*/\\1/g | uniq -u  && exit ${PIPESTATUS[0]})
+    for lib in $swift_runtime_libs; do
+      echo "rsync -auv \"${SWIFT_STDLIB_PATH}/${lib}\" \"${destination}\""
+      rsync -auv "${SWIFT_STDLIB_PATH}/${lib}" "${destination}"
+      code_sign_if_enabled "${destination}/${lib}"
+    done
+  fi
+}
+
+# Signs a framework with the provided identity
+code_sign_if_enabled() {
+  if [ -n "${EXPANDED_CODE_SIGN_IDENTITY}" -a "${CODE_SIGNING_REQUIRED}" != "NO" -a "${CODE_SIGNING_ALLOWED}" != "NO" ]; then
+    # Use the current code_sign_identitiy
+    echo "Code Signing $1 with Identity ${EXPANDED_CODE_SIGN_IDENTITY_NAME}"
+    echo "/usr/bin/codesign --force --sign ${EXPANDED_CODE_SIGN_IDENTITY} ${OTHER_CODE_SIGN_FLAGS} --preserve-metadata=identifier,entitlements \"$1\""
+    /usr/bin/codesign --force --sign ${EXPANDED_CODE_SIGN_IDENTITY} ${OTHER_CODE_SIGN_FLAGS} --preserve-metadata=identifier,entitlements "$1"
+  fi
+}
+
+# Strip invalid architectures
+strip_invalid_archs() {
+  binary="$1"
+  # Get architectures for current file
+  archs="$(lipo -info "$binary" | rev | cut -d ':' -f1 | rev)"
+  stripped=""
+  for arch in $archs; do
+    if ! [[ "${VALID_ARCHS}" == *"$arch"* ]]; then
+      # Strip non-valid architectures in-place
+      lipo -remove "$arch" -output "$binary" "$binary" || exit 1
+      stripped="$stripped $arch"
+    fi
+  done
+  if [[ "$stripped" ]]; then
+    echo "Stripped $binary of architectures:$stripped"
+  fi
+}
+

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner-resources.sh

+#!/bin/sh
+set -e
+
+mkdir -p "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+
+RESOURCES_TO_COPY=${PODS_ROOT}/resources-to-copy-${TARGETNAME}.txt
+> "$RESOURCES_TO_COPY"
+
+XCASSET_FILES=()
+
+case "${TARGETED_DEVICE_FAMILY}" in
+  1,2)
+    TARGET_DEVICE_ARGS="--target-device ipad --target-device iphone"
+    ;;
+  1)
+    TARGET_DEVICE_ARGS="--target-device iphone"
+    ;;
+  2)
+    TARGET_DEVICE_ARGS="--target-device ipad"
+    ;;
+  *)
+    TARGET_DEVICE_ARGS="--target-device mac"
+    ;;
+esac
+
+realpath() {
+  DIRECTORY="$(cd "${1%/*}" && pwd)"
+  FILENAME="${1##*/}"
+  echo "$DIRECTORY/$FILENAME"
+}
+
+install_resource()
+{
+  if [[ "$1" = /* ]] ; then
+    RESOURCE_PATH="$1"
+  else
+    RESOURCE_PATH="${PODS_ROOT}/$1"
+  fi
+  if [[ ! -e "$RESOURCE_PATH" ]] ; then
+    cat << EOM
+error: Resource "$RESOURCE_PATH" not found. Run 'pod install' to update the copy resources script.
+EOM
+    exit 1
+  fi
+  case $RESOURCE_PATH in
+    *.storyboard)
+      echo "ibtool --reference-external-strings-file --errors --warnings --notices --minimum-deployment-target ${!DEPLOYMENT_TARGET_SETTING_NAME} --output-format human-readable-text --compile ${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename \"$RESOURCE_PATH\" .storyboard`.storyboardc $RESOURCE_PATH --sdk ${SDKROOT} ${TARGET_DEVICE_ARGS}"
+      ibtool --reference-external-strings-file --errors --warnings --notices --minimum-deployment-target ${!DEPLOYMENT_TARGET_SETTING_NAME} --output-format human-readable-text --compile "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename \"$RESOURCE_PATH\" .storyboard`.storyboardc" "$RESOURCE_PATH" --sdk "${SDKROOT}" ${TARGET_DEVICE_ARGS}
+      ;;
+    *.xib)
+      echo "ibtool --reference-external-strings-file --errors --warnings --notices --minimum-deployment-target ${!DEPLOYMENT_TARGET_SETTING_NAME} --output-format human-readable-text --compile ${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename \"$RESOURCE_PATH\" .xib`.nib $RESOURCE_PATH --sdk ${SDKROOT} ${TARGET_DEVICE_ARGS}"
+      ibtool --reference-external-strings-file --errors --warnings --notices --minimum-deployment-target ${!DEPLOYMENT_TARGET_SETTING_NAME} --output-format human-readable-text --compile "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename \"$RESOURCE_PATH\" .xib`.nib" "$RESOURCE_PATH" --sdk "${SDKROOT}" ${TARGET_DEVICE_ARGS}
+      ;;
+    *.framework)
+      echo "mkdir -p ${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+      mkdir -p "${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+      echo "rsync -av $RESOURCE_PATH ${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+      rsync -av "$RESOURCE_PATH" "${TARGET_BUILD_DIR}/${FRAMEWORKS_FOLDER_PATH}"
+      ;;
+    *.xcdatamodel)
+      echo "xcrun momc \"$RESOURCE_PATH\" \"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH"`.mom\""
+      xcrun momc "$RESOURCE_PATH" "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH" .xcdatamodel`.mom"
+      ;;
+    *.xcdatamodeld)
+      echo "xcrun momc \"$RESOURCE_PATH\" \"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH" .xcdatamodeld`.momd\""
+      xcrun momc "$RESOURCE_PATH" "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH" .xcdatamodeld`.momd"
+      ;;
+    *.xcmappingmodel)
+      echo "xcrun mapc \"$RESOURCE_PATH\" \"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH" .xcmappingmodel`.cdm\""
+      xcrun mapc "$RESOURCE_PATH" "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/`basename "$RESOURCE_PATH" .xcmappingmodel`.cdm"
+      ;;
+    *.xcassets)
+      ABSOLUTE_XCASSET_FILE=$(realpath "$RESOURCE_PATH")
+      XCASSET_FILES+=("$ABSOLUTE_XCASSET_FILE")
+      ;;
+    *)
+      echo "$RESOURCE_PATH"
+      echo "$RESOURCE_PATH" >> "$RESOURCES_TO_COPY"
+      ;;
+  esac
+}
+
+mkdir -p "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+rsync -avr --copy-links --no-relative --exclude '*/.svn/*' --files-from="$RESOURCES_TO_COPY" / "${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+if [[ "${ACTION}" == "install" ]] && [[ "${SKIP_INSTALL}" == "NO" ]]; then
+  mkdir -p "${INSTALL_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+  rsync -avr --copy-links --no-relative --exclude '*/.svn/*' --files-from="$RESOURCES_TO_COPY" / "${INSTALL_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+fi
+rm -f "$RESOURCES_TO_COPY"
+
+if [[ -n "${WRAPPER_EXTENSION}" ]] && [ "`xcrun --find actool`" ] && [ -n "$XCASSET_FILES" ]
+then
+  # Find all other xcassets (this unfortunately includes those of path pods and other targets).
+  OTHER_XCASSETS=$(find "$PWD" -iname "*.xcassets" -type d)
+  while read line; do
+    if [[ $line != "`realpath $PODS_ROOT`*" ]]; then
+      XCASSET_FILES+=("$line")
+    fi
+  done <<<"$OTHER_XCASSETS"
+
+  printf "%s\0" "${XCASSET_FILES[@]}" | xargs -0 xcrun actool --output-format human-readable-text --notices --warnings --platform "${PLATFORM_NAME}" --minimum-deployment-target "${!DEPLOYMENT_TARGET_SETTING_NAME}" ${TARGET_DEVICE_ARGS} --compress-pngs --compile "${BUILT_PRODUCTS_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}"
+fi

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig

+GCC_PREPROCESSOR_DEFINITIONS = $(inherited) COCOAPODS=1
+HEADER_SEARCH_PATHS = $(inherited) "${PODS_ROOT}/Headers/Public"
+OTHER_CFLAGS = $(inherited) -isystem "${PODS_ROOT}/Headers/Public"
+OTHER_LDFLAGS = $(inherited) -ObjC
+PODS_BUILD_DIR = $BUILD_DIR
+PODS_CONFIGURATION_BUILD_DIR = $PODS_BUILD_DIR/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)
+PODS_ROOT = ${SRCROOT}/Pods

examples/layers/ios/Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig

+GCC_PREPROCESSOR_DEFINITIONS = $(inherited) COCOAPODS=1
+HEADER_SEARCH_PATHS = $(inherited) "${PODS_ROOT}/Headers/Public"
+OTHER_CFLAGS = $(inherited) -isystem "${PODS_ROOT}/Headers/Public"
+OTHER_LDFLAGS = $(inherited) -ObjC
+PODS_BUILD_DIR = $BUILD_DIR
+PODS_CONFIGURATION_BUILD_DIR = $PODS_BUILD_DIR/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)
+PODS_ROOT = ${SRCROOT}/Pods

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

+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "0830"
+   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/layers/ios/Runner.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/layers/ios/Runner/AppDelegate.h

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

examples/layers/ios/Runner/AppDelegate.m

+#include "AppDelegate.h"
+
+@implementation AppDelegate
+
+- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+    // Override point for customization after application launch.
+    return YES;
+}
+
+- (void)applicationWillResignActive:(UIApplication *)application {
+    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
+    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
+}
+
+- (void)applicationDidEnterBackground:(UIApplication *)application {
+    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
+    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
+}
+
+- (void)applicationWillEnterForeground:(UIApplication *)application {
+    // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
+}
+
+- (void)applicationDidBecomeActive:(UIApplication *)application {
+    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
+}
+
+- (void)applicationWillTerminate:(UIApplication *)application {
+    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
+}
+
+@end

examples/layers/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/layers/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/layers/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/layers/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>layers</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>UIRequiredDeviceCapabilities</key>
+	<array>
+		<string>arm64</string>
+	</array>
+	<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/layers/ios/Runner/main.m

+#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/layers/pubspec.yaml

@@ -10,3 +10,4 @@ dev_dependencies:
 flutter:
   assets:
     - services/data.json
+  uses-material-design: true

examples/layers/rendering/src/sector_layout.dart

@@ -15,7 +15,8 @@ class SectorConstraints extends Constraints {
     this.maxDeltaRadius: double.INFINITY,
     this.minDeltaTheta: 0.0,
     this.maxDeltaTheta: kTwoPi
-  });
+  }) : assert(maxDeltaRadius >= minDeltaRadius),
+       assert(maxDeltaTheta >= minDeltaTheta);
 
   const SectorConstraints.tight({ double deltaRadius: 0.0, double deltaTheta: 0.0 })
     : minDeltaRadius = deltaRadius,
@@ -216,12 +217,16 @@ class RenderSectorRing extends RenderSectorWithChildren {
     BoxDecoration decoration,
     double deltaRadius: double.INFINITY,
     double padding: 0.0
-  }) : _padding = padding, _desiredDeltaRadius = deltaRadius, super(decoration);
+  }) : _padding = padding,
+       assert(deltaRadius >= 0.0),
+       _desiredDeltaRadius = deltaRadius,
+       super(decoration);
 
   double _desiredDeltaRadius;
   double get desiredDeltaRadius => _desiredDeltaRadius;
   set desiredDeltaRadius(double value) {
     assert(value != null);
+    assert(value >= 0);
     if (_desiredDeltaRadius != value) {
       _desiredDeltaRadius = value;
       markNeedsLayout();
@@ -249,11 +254,11 @@ class RenderSectorRing extends RenderSectorWithChildren {
   @override
   SectorDimensions getIntrinsicDimensions(SectorConstraints constraints, double radius) {
     final double outerDeltaRadius = constraints.constrainDeltaRadius(desiredDeltaRadius);
-    final double innerDeltaRadius = outerDeltaRadius - padding * 2.0;
+    final double innerDeltaRadius = math.max(0.0, outerDeltaRadius - padding * 2.0);
     final double childRadius = radius + padding;
     final double paddingTheta = math.atan(padding / (radius + outerDeltaRadius));
     double innerTheta = paddingTheta; // increments with each child
-    double remainingDeltaTheta = constraints.maxDeltaTheta - (innerTheta + paddingTheta);
+    double remainingDeltaTheta = math.max(0.0, constraints.maxDeltaTheta - (innerTheta + paddingTheta));
     RenderSector child = firstChild;
     while (child != null) {
       final SectorConstraints innerConstraints = new SectorConstraints(
@@ -489,10 +494,12 @@ class RenderBoxToRenderSectorAdapter extends RenderBox with RenderObjectWithChil
     assert(child.parentData is SectorParentData);
     assert(width != null);
     assert(height != null);
-    final double maxChildDeltaRadius = math.min(width, height) / 2.0 - innerRadius;
+    if (!width.isFinite && !height.isFinite)
+      return Size.zero;
+    final double maxChildDeltaRadius = math.max(0.0, math.min(width, height) / 2.0 - innerRadius);
     final SectorDimensions childDimensions = child.getIntrinsicDimensions(new SectorConstraints(maxDeltaRadius: maxChildDeltaRadius), innerRadius);
     final double dimension = (innerRadius + childDimensions.deltaRadius) * 2.0;
-    return constraints.constrain(new Size(dimension, dimension));
+    return new Size.square(dimension);
   }
 
   @override

examples/layers/test/sector_test.dart

@@ -2,12 +2,17 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:test/test.dart';
+import 'package:flutter_test/flutter_test.dart';
 
 import '../rendering/src/sector_layout.dart';
+import '../widgets/sectors.dart';
 
 void main() {
   test('SectorConstraints', () {
     expect(const SectorConstraints().isTight, isFalse);
   });
+
+  testWidgets('Sector Sixes', (WidgetTester tester) {
+    tester.pumpWidget(new SectorApp());
+  });
 }

examples/stocks/lib/stock_data.dart

@@ -39,10 +39,10 @@ class Stock {
 }
 
 class StockData {
-  List<List<String>> _data;
-
   StockData(this._data);
 
+  final List<List<String>> _data;
+
   void appendTo(Map<String, Stock> stocks, List<String> symbols) {
     for (List<String> fields in _data) {
       final Stock stock = new Stock.fromFields(fields);

packages/flutter/lib/src/rendering/error.dart

@@ -51,7 +51,7 @@ class RenderErrorBox extends RenderBox {
         );
         _paragraph = builder.build();
       }
-    } catch (e) { }
+    } catch (e) { } // ignore: empty_catches
   }
 
   /// The message to attempt to display at paint time.
@@ -114,6 +114,6 @@ class RenderErrorBox extends RenderBox {
 
         context.canvas.drawParagraph(_paragraph, offset);
       }
-    } catch (e) { }
+    } catch (e) { } // ignore: empty_catches
   }
 }

packages/flutter/lib/src/widgets/framework.dart

@@ -3006,7 +3006,7 @@ class ErrorWidget extends LeafRenderObjectWidget {
   static String _stringify(Object exception) {
     try {
       return exception.toString();
-    } catch (e) { }
+    } catch (e) { } // ignore: empty_catches
     return 'Error';
   }
 

packages/flutter_tools/lib/src/ios/mac.dart

@@ -72,6 +72,7 @@ class Xcode {
           else
             _eulaSigned = true;
         } catch (error) {
+          _eulaSigned = false;
         }
       }
     } catch (error) {

packages/flutter_tools/lib/src/runner/flutter_command_runner.dart

@@ -280,7 +280,11 @@ class FlutterCommandRunner extends CommandRunner<Null> {
           if (engineSourcePath == '/' || engineSourcePath.isEmpty || !dirExists)
             engineSourcePath = null;
         }
-      } on FileSystemException { } on FormatException { }
+      } on FileSystemException {
+        engineSourcePath = null;
+      } on FormatException {
+        engineSourcePath = null;
+      }
 
       if (engineSourcePath == null)
         engineSourcePath = _tryEnginePath(fs.path.join(Cache.flutterRoot, '../engine/src'));

packages/flutter_tools/templates/create/android.tmpl/app/src/main/AndroidManifest.xml.tmpl

@@ -5,7 +5,8 @@
 
     <uses-sdk android:minSdkVersion="{{androidMinApiLevel}}" android:targetSdkVersion="21" />
 
-    <!-- The INTERNET permission is required for development. Specifically, flutter needs it to communicate with the running application
+    <!-- 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"/>