Add integration test of textures (#13122)

dev/devicelab/bin/tasks/external_ui_integration_test.dart

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/tasks/integration_tests.dart';
+
+Future<Null> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.android;
+  await task(createExternalUiIntegrationTest());
+}

dev/devicelab/bin/tasks/external_ui_integration_test_ios.dart

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/tasks/integration_tests.dart';
+
+Future<Null> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.ios;
+  await task(createExternalUiIntegrationTest());
+}

dev/devicelab/lib/tasks/integration_tests.dart

@@ -31,6 +31,13 @@ TaskFunction createFlavorsTest() {
   );
 }
 
+TaskFunction createExternalUiIntegrationTest() {
+  return new DriverTest(
+    '${flutterDirectory.path}/dev/integration_tests/external_ui',
+    'lib/main.dart',
+  );
+}
+
 TaskFunction createPlatformChannelSampleTest() {
   return new DriverTest(
     '${flutterDirectory.path}/examples/platform_channel',

dev/devicelab/manifest.yaml

@@ -71,6 +71,13 @@ tasks:
     stage: devicelab
     required_agent_capabilities: ["has-android-device"]
 
+  external_ui_integration_test:
+    description: >
+      Checks that external UIs work on Android.
+    stage: devicelab
+    required_agent_capabilities: ["has-android-device"]
+    flaky: true
+
   platform_interaction_test:
     description: >
       Checks platform interaction on Android.
@@ -185,6 +192,13 @@ tasks:
     stage: devicelab_ios
     required_agent_capabilities: ["has-ios-device"]
 
+  external_ui_integration_test_ios:
+    description: >
+      Checks that external UIs work on iOS.
+    stage: devicelab
+    required_agent_capabilities: ["has-ios-device"]
+    flaky: true
+
   channels_integration_test_ios:
     description: >
       Checks that platform channels work on iOS.

dev/integration_tests/external_ui/.gitignore

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

dev/integration_tests/external_ui/README.md

+# external_ui
+
+A Flutter project for testing external texture rendering.

dev/integration_tests/external_ui/android/.gitignore

+*.iml
+.gradle
+/local.properties
+/.idea/workspace.xml
+/.idea/libraries
+.DS_Store
+/build
+/captures
+GeneratedPluginRegistrant.java

dev/integration_tests/external_ui/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 '25.0.3'
+
+    lintOptions {
+        disable 'InvalidPackage'
+    }
+
+    defaultConfig {
+        applicationId "com.yourcompany.externalui"
+        minSdkVersion 16
+        targetSdkVersion 25
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+    }
+
+    buildTypes {
+        release {
+            signingConfig signingConfigs.debug
+        }
+    }
+}
+
+flutter {
+    source '../..'
+}
+
+dependencies {
+    androidTestCompile 'com.android.support:support-annotations:25.4.0'
+    androidTestCompile 'com.android.support.test:runner:0.5'
+    androidTestCompile 'com.android.support.test:rules:0.5'
+}

dev/integration_tests/external_ui/android/app/src/main/AndroidManifest.xml

+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.yourcompany.externalui">
+
+    <uses-permission android:name="android.permission.INTERNET"/>
+
+    <application
+        android:name="io.flutter.app.FlutterApplication"
+        android:label="external_ui">
+        <activity
+            android:name=".MainActivity"
+            android:launchMode="singleTop"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale"
+            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>

dev/integration_tests/external_ui/android/app/src/main/java/com/yourcompany/externalui/MainActivity.java

+// Copyright 2017 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.
+
+package com.yourcompany.externalui;
+
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.SurfaceTexture;
+import android.os.Build;
+import android.os.Bundle;
+import android.view.Surface;
+import android.view.SurfaceHolder;
+
+import java.util.Timer;
+import java.util.TimerTask;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import io.flutter.app.FlutterActivity;
+import io.flutter.plugin.common.MethodCall;
+import io.flutter.plugin.common.MethodChannel;
+import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
+import io.flutter.plugin.common.MethodChannel.Result;
+import io.flutter.view.TextureRegistry;
+import io.flutter.view.TextureRegistry.SurfaceTextureEntry;
+
+public class MainActivity extends FlutterActivity {
+  private Surface surface;
+  private SurfaceTexture texture;
+  private Timer producerTimer;
+  private Timer consumerTimer;
+  private long startTime;
+  private long endTime;
+  private AtomicInteger framesProduced = new AtomicInteger(0);
+  private AtomicInteger framesConsumed = new AtomicInteger(0);
+
+  @Override
+  protected void onCreate(Bundle savedInstanceState) {
+    super.onCreate(savedInstanceState);
+
+    final MethodChannel channel = new MethodChannel(getFlutterView(), "texture");
+    channel.setMethodCallHandler(new MethodCallHandler() {
+      @Override
+      public void onMethodCall(MethodCall methodCall, Result result) {
+        switch (methodCall.method) {
+          case "start":
+            framesProduced.set(0);
+            framesConsumed.set(0);
+            final int fps = methodCall.arguments();
+            final FrameRenderer renderer = new FrameRenderer(surface);
+            producerTimer = new Timer();
+            producerTimer.scheduleAtFixedRate(new TimerTask() {
+              @Override
+              public void run() {
+                renderer.drawFrame();
+                framesProduced.incrementAndGet();
+              }
+            }, 0, 1000 / fps);
+            consumerTimer = new Timer();
+            consumerTimer.scheduleAtFixedRate(new TimerTask() {
+              private long lastTimestamp = -1L;
+
+              @Override
+              public void run() {
+                final long timestamp = texture.getTimestamp();
+                // The texture's timestamp is updated on consumption.
+                // We detect the change by asking very frequently.
+                if (timestamp != lastTimestamp) {
+                  lastTimestamp = timestamp;
+                  framesConsumed.incrementAndGet();
+                }
+              }
+            }, 0, 1);
+            startTime = System.currentTimeMillis();
+            result.success(null);
+            break;
+          case "stop":
+            producerTimer.cancel();
+            consumerTimer.cancel();
+            endTime = System.currentTimeMillis();
+            result.success(null);
+            break;
+          case "getProducedFrameRate":
+            result.success(framesProduced.get() * 1000 / (double) (endTime - startTime));
+            break;
+          case "getConsumedFrameRate":
+            result.success(framesConsumed.get() * 1000 / (double) (endTime - startTime));
+            break;
+          default: result.notImplemented();
+        }
+      }
+    });
+
+    getFlutterView().getHolder().addCallback(new SurfaceHolder.Callback() {
+      @Override
+      public void surfaceCreated(SurfaceHolder holder) {
+        final SurfaceTextureEntry textureEntry = getFlutterView().createSurfaceTexture();
+        texture = textureEntry.surfaceTexture();
+        texture.setDefaultBufferSize(300, 200);
+        surface = new Surface(texture);
+      }
+
+      @Override
+      public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
+      }
+
+      @Override
+      public void surfaceDestroyed(SurfaceHolder holder) {
+      }
+    });
+  }
+
+  @Override
+  protected void onDestroy() {
+    if (surface != null) {
+      surface.release();
+    }
+    super.onDestroy();
+  }
+}
+
+class FrameRenderer {
+  private final Surface surface;
+  private final Paint paint;
+  private int frameCount = 0;
+
+  FrameRenderer(Surface surface) {
+    this.surface = surface;
+    this.paint = new Paint();
+    paint.setColor(0xffff0000);
+    paint.setTextSize(48.0f);
+    paint.setAntiAlias(true);
+  }
+
+  void drawFrame() {
+    final Canvas canvas = surface.lockCanvas(null);
+    canvas.drawColor(0xff000000);
+    canvas.drawText(String.valueOf(++frameCount), 20, 120, paint);
+    surface.unlockCanvasAndPost(canvas);
+  }
+}

dev/integration_tests/external_ui/android/build.gradle

+buildscript {
+    repositories {
+        jcenter()
+        maven {
+            url "https://maven.google.com"
+        }
+    }
+
+    dependencies {
+        classpath 'com.android.tools.build:gradle:2.3.3'
+    }
+}
+
+allprojects {
+    repositories {
+        jcenter()
+        maven {
+            url "https://maven.google.com"
+        }
+    }
+}
+
+rootProject.buildDir = '../build'
+subprojects {
+    project.buildDir = "${rootProject.buildDir}/${project.name}"
+    project.evaluationDependsOn(':app')
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}

dev/integration_tests/external_ui/android/gradle.properties

+org.gradle.jvmargs=-Xmx1536M

dev/integration_tests/external_ui/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-3.3-all.zip

dev/integration_tests/external_ui/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
+}

dev/integration_tests/external_ui/ios/.gitignore

+.idea/
+.vagrant/
+.sconsign.dblite
+.svn/
+
+.DS_Store
+*.swp
+profile
+
+DerivedData/
+build/
+GeneratedPluginRegistrant.h
+GeneratedPluginRegistrant.m
+
+*.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
+
+Pods/

dev/integration_tests/external_ui/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>

dev/integration_tests/external_ui/ios/Flutter/Debug.xcconfig

+#include "Generated.xcconfig"

dev/integration_tests/external_ui/ios/Flutter/Release.xcconfig

+#include "Generated.xcconfig"

dev/integration_tests/external_ui/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata

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

dev/integration_tests/external_ui/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>

dev/integration_tests/external_ui/ios/Runner.xcworkspace/contents.xcworkspacedata

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

dev/integration_tests/external_ui/ios/Runner/AppDelegate.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import <UIKit/UIKit.h>
+#import <Flutter/Flutter.h>
+
+@interface AppDelegate : FlutterAppDelegate<FlutterTexture>
+
+@end

dev/integration_tests/external_ui/ios/Runner/AppDelegate.m

+// Copyright 2017 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.
+
+#include "AppDelegate.h"
+
+@interface AppDelegate ()
+  @property (atomic) uint64_t textureId;
+  @property (atomic) int framesProduced;
+  @property (atomic) int framesConsumed;
+  @property (atomic) int lastFrameConsumed;
+  @property (atomic) double startTime;
+  @property (atomic) double endTime;
+  @property (atomic) double frameRate;
+  @property (atomic) double frameStartTime;
+  @property (atomic) NSTimer* timer;
+
+  - (void)tick:(NSTimer*)timer;
+@end
+
+@implementation AppDelegate
+
+- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+  FlutterViewController* flutterController =
+      (FlutterViewController*)self.window.rootViewController;
+  FlutterMethodChannel* channel =
+      [FlutterMethodChannel methodChannelWithName:@"texture"
+                                  binaryMessenger:flutterController];
+  [channel setMethodCallHandler:^(FlutterMethodCall* call, FlutterResult result) {
+      if ([@"start" isEqualToString:call.method]) {
+        _framesProduced = 0;
+        _framesConsumed = 0;
+        _frameRate = 1.0 / [(NSNumber*) call.arguments intValue];
+        _timer = [NSTimer scheduledTimerWithTimeInterval:_frameRate
+                                                  target:self
+                                                selector:@selector(tick:)
+                                                userInfo:nil
+                                                 repeats:YES];
+        _startTime = [[NSDate date] timeIntervalSince1970];
+        result(nil);
+      } else if ([@"stop" isEqualToString:call.method]) {
+        [_timer invalidate];
+        _endTime = [[NSDate date] timeIntervalSince1970];
+        result(nil);
+      } else if ([@"getProducedFrameRate" isEqualToString:call.method]) {
+        result(@(_framesProduced / (_endTime - _startTime)));
+      } else if ([@"getConsumedFrameRate" isEqualToString:call.method]) {
+        result(@(_framesConsumed / (_endTime - _startTime)));
+      } else {
+        result(FlutterMethodNotImplemented);
+      }
+  }];
+  _textureId = [flutterController registerTexture:self];
+  return [super application:application didFinishLaunchingWithOptions:launchOptions];
+}
+
+- (void)tick:(NSTimer*)timer {
+  FlutterViewController* flutterController =
+      (FlutterViewController*)self.window.rootViewController;
+  [flutterController textureFrameAvailable:_textureId];
+  _frameStartTime = [[NSDate date] timeIntervalSince1970];
+  // We just pretend to be producing a frame.
+  _framesProduced++;
+}
+
+- (CVPixelBufferRef)copyPixelBuffer {
+  double now = [[NSDate date] timeIntervalSince1970];
+  if (now < _frameStartTime
+      || _frameStartTime + _frameRate < now
+      || _framesProduced == _lastFrameConsumed) return nil;
+  _framesConsumed++;
+  _lastFrameConsumed = _framesProduced;
+  // We just pretend to be handing over the produced frame to the consumer.
+  return nil;
+}
+@end

dev/integration_tests/external_ui/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>

dev/integration_tests/external_ui/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>

dev/integration_tests/external_ui/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>external_ui</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>

dev/integration_tests/external_ui/ios/Runner/main.m

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import <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]));
+  }
+}

dev/integration_tests/external_ui/lib/main.dart

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'package:flutter/material.dart';
+import 'package:flutter/scheduler.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_driver/driver_extension.dart';
+
+void main() {
+  enableFlutterDriverExtension();
+  runApp(new MyApp());
+}
+
+class MyApp extends StatefulWidget {
+  @override
+  State createState() => new MyAppState();
+}
+
+const MethodChannel channel = const MethodChannel('texture');
+
+enum FrameState { initial, slow, afterSlow, fast, afterFast }
+
+class MyAppState extends State<MyApp> with SingleTickerProviderStateMixin {
+  int _widgetBuilds = 0;
+  FrameState _state;
+  String _summary = '';
+  IconData _icon;
+  double _flutterFrameRate;
+
+  Future<Null> _summarizeStats() async {
+    final double framesProduced = await channel.invokeMethod('getProducedFrameRate');
+    final double framesConsumed = await channel.invokeMethod('getConsumedFrameRate');
+    _summary = '''
+Produced: ${framesProduced.toStringAsFixed(1)}fps
+Consumed: ${framesConsumed.toStringAsFixed(1)}fps
+Widget builds: $_widgetBuilds''';
+  }
+
+  Future<Null> _nextState() async {
+    switch (_state) {
+    case FrameState.initial:
+      _widgetBuilds = 0;
+      _summary = 'Producing texture frames at .5x speed...';
+      _state = FrameState.slow;
+      _icon = Icons.stop;
+      channel.invokeMethod('start', _flutterFrameRate ~/ 2);
+      break;
+    case FrameState.slow:
+      await channel.invokeMethod('stop');
+      await _summarizeStats();
+      _icon = Icons.fast_forward;
+      _state = FrameState.afterSlow;
+      break;
+    case FrameState.afterSlow:
+      _widgetBuilds = 0;
+      _summary = 'Producing texture frames at 2x speed...';
+      _state = FrameState.fast;
+      _icon = Icons.stop;
+      channel.invokeMethod('start', (_flutterFrameRate * 2).toInt());
+      break;
+    case FrameState.fast:
+      await channel.invokeMethod('stop');
+      await _summarizeStats();
+      _state = FrameState.afterFast;
+      _icon = Icons.replay;
+      break;
+    case FrameState.afterFast:
+      _summary = 'Press play to start again';
+      _state = FrameState.initial;
+      _icon = Icons.play_arrow;
+      break;
+    }
+    setState(() {});
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _calibrate();
+  }
+
+  /// Measures Flutter's frame rate.
+  Future<Null> _calibrate() async {
+    await new Future<Null>.delayed(const Duration(milliseconds: 200));
+    DateTime startTime;
+    int tickCount = 0;
+    Ticker ticker;
+    ticker = createTicker((Duration _) {
+      tickCount++;
+      if (tickCount == 120) {
+        final Duration elapsed = new DateTime.now().difference(startTime);
+        ticker.stop();
+        ticker.dispose();
+        setState(() {
+          _flutterFrameRate = tickCount * 1000 / elapsed.inMilliseconds;
+          _summary = 'Flutter frame rate is ${_flutterFrameRate.toStringAsFixed(1)}fps.\nPress play to produce texture frames.';
+          _icon = Icons.play_arrow;
+          _state = FrameState.initial;
+        });
+      }
+    });
+    ticker.start();
+    startTime = new DateTime.now();
+    setState(() {
+      _summary = 'Calibrating...';
+      _icon = null;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    _widgetBuilds++;
+    return new MaterialApp(
+      home: new Scaffold(
+        body: new Center(
+          child: new Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: <Widget>[
+              new Container(
+                width: 300.0,
+                height: 200.0,
+                child: const Texture(textureId: 0),
+              ),
+              new Container(
+                width: 300.0,
+                height: 60.0,
+                color: Colors.grey,
+                child: new Center(
+                  child: new Text(
+                    _summary,
+                    key: const ValueKey<String>('summary'),
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+        floatingActionButton: (_icon == null ? null : new FloatingActionButton(
+          key: const ValueKey<String>('fab'),
+          child: new Icon(_icon),
+          onPressed: _nextState,
+        )),
+      ),
+    );
+  }
+}

dev/integration_tests/external_ui/pubspec.yaml

+name: external_ui
+description: A test of Flutter integrating external UIs.
+
+dependencies:
+  flutter:
+    sdk: flutter
+  flutter_driver:
+    sdk: flutter
+
+flutter:
+  uses-material-design: true

dev/integration_tests/external_ui/test_driver/main_test.dart

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'package:flutter_driver/flutter_driver.dart';
+import 'package:test/test.dart';
+
+final RegExp calibrationRegExp = new RegExp('Flutter frame rate is (.*)fps');
+final RegExp statsRegExp = new RegExp('Produced: (.*)fps\nConsumed: (.*)fps\nWidget builds: (.*)');
+const Duration samplingTime = const Duration(seconds: 3);
+
+Future<Null> main() async {
+  group('texture suite', () {
+    FlutterDriver driver;
+
+    setUpAll(() async {
+      driver = await FlutterDriver.connect();
+      // TODO(mravn): the following pause appears necessary on iOS to avoid
+      // inflating elements too early (when there is no size).
+      await new Future<Null>.delayed(const Duration(seconds: 1));
+    });
+
+    test('texture rendering', () async {
+      final SerializableFinder fab = find.byValueKey('fab');
+      final SerializableFinder summary = find.byValueKey('summary');
+
+      // Wait for calibration to complete and fab to appear.
+      await driver.waitFor(fab, timeout: const Duration(seconds: 10));
+
+      final String calibrationResult = await driver.getText(summary);
+      final Match matchCalibration = calibrationRegExp.matchAsPrefix(calibrationResult);
+      expect(matchCalibration, isNotNull);
+      final double flutterFrameRate = double.parse(matchCalibration.group(1));
+
+      // Texture frame stats at 0.5x Flutter frame rate
+      await driver.tap(fab);
+      await new Future<Null>.delayed(samplingTime);
+      await driver.tap(fab);
+
+      final String statsSlow = await driver.getText(summary);
+      final Match matchSlow = statsRegExp.matchAsPrefix(statsSlow);
+      expect(matchSlow, isNotNull);
+      expect(double.parse(matchSlow.group(1)), closeTo(flutterFrameRate / 2.0, 5.0));
+      expect(double.parse(matchSlow.group(2)), closeTo(flutterFrameRate / 2.0, 5.0));
+      expect(int.parse(matchSlow.group(3)), 1);
+
+      // Texture frame stats at 2.0x Flutter frame rate
+      await driver.tap(fab);
+      await new Future<Null>.delayed(samplingTime);
+      await driver.tap(fab);
+
+      final String statsFast = await driver.getText(summary);
+      final Match matchFast = statsRegExp.matchAsPrefix(statsFast);
+      expect(matchFast, isNotNull);
+      expect(double.parse(matchFast.group(1)), closeTo(flutterFrameRate * 2.0, 10.0));
+      expect(double.parse(matchFast.group(2)), closeTo(flutterFrameRate, 10.0));
+      expect(int.parse(matchFast.group(3)), 1);
+    });
+
+    tearDownAll(() async {
+      driver?.close();
+    });
+  });
+}