Fix preview rotation on iOS

packages/camera/camera/example/lib/main.dart

@@ -157,17 +157,17 @@ class _CameraExampleHomeState extends State<CameraExampleHome> with WidgetsBindi
         ),
       );
     } else {
-      return AspectRatio(
-        aspectRatio: 1 / controller.value.aspectRatio,
-        child: Listener(
-          onPointerDown: (_) => _pointers++,
-          onPointerUp: (_) => _pointers--,
+      return Listener(
+        onPointerDown: (_) => _pointers++,
+        onPointerUp: (_) => _pointers--,
+        child: CameraPreview(
+          controller,
           child: LayoutBuilder(builder: (BuildContext context, BoxConstraints constraints) {
             return GestureDetector(
+              behavior: HitTestBehavior.opaque,
               onScaleStart: _handleScaleStart,
               onScaleUpdate: _handleScaleUpdate,
               onTapDown: (details) => onViewFinderTap(details, constraints),
-              child: CameraPreview(controller),
             );
           }),
         ),

packages/camera/camera/ios/Classes/CameraPlugin.m

@@ -1086,6 +1086,7 @@ @interface CameraPlugin ()
 @property(readonly, nonatomic) NSObject<FlutterTextureRegistry> *registry;
 @property(readonly, nonatomic) NSObject<FlutterBinaryMessenger> *messenger;
 @property(readonly, nonatomic) FLTCam *camera;
+@property(readonly, nonatomic) FlutterMethodChannel *deviceEventMethodChannel;
 @end
 
 @implementation CameraPlugin {
@@ -1106,9 +1107,50 @@ - (instancetype)initWithRegistry:(NSObject<FlutterTextureRegistry> *)registry
   NSAssert(self, @"super init cannot be nil");
   _registry = registry;
   _messenger = messenger;
+  [self initDeviceEventMethodChannel];
+  [self startOrientationListener];
   return self;
 }
 
+- (void)initDeviceEventMethodChannel {
+  _deviceEventMethodChannel =
+      [FlutterMethodChannel methodChannelWithName:@"flutter.io/cameraPlugin/device"
+                                  binaryMessenger:_messenger];
+}
+
+- (void)startOrientationListener {
+  [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(orientationChanged:)
+                                               name:UIDeviceOrientationDidChangeNotification
+                                             object:[UIDevice currentDevice]];
+}
+
+- (void)orientationChanged:(NSNotification *)note {
+  UIDevice *device = note.object;
+
+  switch (device.orientation) {
+    case UIDeviceOrientationPortrait:
+      [_deviceEventMethodChannel invokeMethod:@"orientation_changed"
+                                    arguments:@{@"orientation" : @"portraitUp"}];
+      break;
+    case UIDeviceOrientationPortraitUpsideDown:
+      [_deviceEventMethodChannel invokeMethod:@"orientation_changed"
+                                    arguments:@{@"orientation" : @"portraitDown"}];
+      break;
+    case UIDeviceOrientationLandscapeRight:
+      [_deviceEventMethodChannel invokeMethod:@"orientation_changed"
+                                    arguments:@{@"orientation" : @"landscapeLeft"}];
+      break;
+    case UIDeviceOrientationLandscapeLeft:
+      [_deviceEventMethodChannel invokeMethod:@"orientation_changed"
+                                    arguments:@{@"orientation" : @"landscapeRight"}];
+      break;
+    default:
+      break;
+  };
+}
+
 - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result {
   if (_dispatchQueue == nil) {
     _dispatchQueue = dispatch_queue_create("io.flutter.camera.dispatchqueue", NULL);

packages/camera/camera/lib/src/camera_controller.dart

@@ -41,6 +41,7 @@ class CameraValue {
     this.flashMode,
     this.exposureMode,
     this.exposurePointSupported,
+    this.deviceOrientation,
   }) : _isRecordingPaused = isRecordingPaused;
 
   /// Creates a new camera controller state for an uninitialized controller.
@@ -53,6 +54,7 @@ class CameraValue {
           isRecordingPaused: false,
           flashMode: FlashMode.auto,
           exposurePointSupported: false,
+          deviceOrientation: DeviceOrientation.portraitUp,
         );
 
   /// True after [CameraController.initialize] has completed successfully.
@@ -102,6 +104,9 @@ class CameraValue {
   /// Whether setting the exposure point is supported.
   final bool exposurePointSupported;
 
+  /// The current device orientation.
+  final DeviceOrientation deviceOrientation;
+
   /// Creates a modified copy of the object.
   ///
   /// Explicitly specified fields get the specified value, all other fields get
@@ -117,6 +122,7 @@ class CameraValue {
     FlashMode flashMode,
     ExposureMode exposureMode,
     bool exposurePointSupported,
+    DeviceOrientation deviceOrientation,
   }) {
     return CameraValue(
       isInitialized: isInitialized ?? this.isInitialized,
@@ -128,8 +134,8 @@ class CameraValue {
       isRecordingPaused: isRecordingPaused ?? _isRecordingPaused,
       flashMode: flashMode ?? this.flashMode,
       exposureMode: exposureMode ?? this.exposureMode,
-      exposurePointSupported:
-          exposurePointSupported ?? this.exposurePointSupported,
+      exposurePointSupported: exposurePointSupported ?? this.exposurePointSupported,
+      deviceOrientation: deviceOrientation ?? this.deviceOrientation,
     );
   }
 
@@ -143,7 +149,8 @@ class CameraValue {
         'isStreamingImages: $isStreamingImages, '
         'flashMode: $flashMode, '
         'exposureMode: $exposureMode, '
-        'exposurePointSupported: $exposurePointSupported)';
+        'exposurePointSupported: $exposurePointSupported, '
+        'deviceOrientation: $deviceOrientation)';
   }
 }
 
@@ -180,6 +187,7 @@ class CameraController extends ValueNotifier<CameraValue> {
   bool _isDisposed = false;
   StreamSubscription<dynamic> _imageStreamSubscription;
   FutureOr<bool> _initCalled;
+  StreamSubscription _deviceOrientationSubscription;
 
   /// Checks whether [CameraController.dispose] has completed successfully.
   ///
@@ -204,32 +212,32 @@ class CameraController extends ValueNotifier<CameraValue> {
     try {
       Completer<CameraInitializedEvent> _initializeCompleter = Completer();
 
+      _deviceOrientationSubscription = CameraPlatform.instance.onDeviceOrientationChanged().listen((event) {
+        value = value.copyWith(
+          deviceOrientation: event.orientation,
+        );
+      });
+
       _cameraId = await CameraPlatform.instance.createCamera(
         description,
         resolutionPreset,
         enableAudio: enableAudio,
       );
 
-      unawaited(CameraPlatform.instance
-          .onCameraInitialized(_cameraId)
-          .first
-          .then((event) {
+      unawaited(CameraPlatform.instance.onCameraInitialized(_cameraId).first.then((event) {
         _initializeCompleter.complete(event);
       }));
 
       await CameraPlatform.instance.initializeCamera(_cameraId);
 
       value = value.copyWith(
         isInitialized: true,
-        previewSize: await _initializeCompleter.future
-            .then((CameraInitializedEvent event) => Size(
-                  event.previewWidth,
-                  event.previewHeight,
-                )),
-        exposureMode: await _initializeCompleter.future
-            .then((event) => event.exposureMode),
-        exposurePointSupported: await _initializeCompleter.future
-            .then((event) => event.exposurePointSupported),
+        previewSize: await _initializeCompleter.future.then((CameraInitializedEvent event) => Size(
+              event.previewWidth,
+              event.previewHeight,
+            )),
+        exposureMode: await _initializeCompleter.future.then((event) => event.exposureMode),
+        exposurePointSupported: await _initializeCompleter.future.then((event) => event.exposurePointSupported),
       );
     } on PlatformException catch (e) {
       throw CameraException(e.code, e.message);
@@ -298,8 +306,7 @@ class CameraController extends ValueNotifier<CameraValue> {
   ///
   // TODO(bmparr): Add settings for resolution and fps.
   Future<void> startImageStream(onLatestImageAvailable onAvailable) async {
-    assert(defaultTargetPlatform == TargetPlatform.android ||
-        defaultTargetPlatform == TargetPlatform.iOS);
+    assert(defaultTargetPlatform == TargetPlatform.android || defaultTargetPlatform == TargetPlatform.iOS);
 
     if (!value.isInitialized || _isDisposed) {
       throw CameraException(
@@ -326,10 +333,8 @@ class CameraController extends ValueNotifier<CameraValue> {
     } on PlatformException catch (e) {
       throw CameraException(e.code, e.message);
     }
-    const EventChannel cameraEventChannel =
-        EventChannel('plugins.flutter.io/camera/imageStream');
-    _imageStreamSubscription =
-        cameraEventChannel.receiveBroadcastStream().listen(
+    const EventChannel cameraEventChannel = EventChannel('plugins.flutter.io/camera/imageStream');
+    _imageStreamSubscription = cameraEventChannel.receiveBroadcastStream().listen(
       (dynamic imageData) {
         onAvailable(CameraImage.fromPlatformData(imageData));
       },
@@ -344,8 +349,7 @@ class CameraController extends ValueNotifier<CameraValue> {
   /// The `stopImageStream` method is only available on Android and iOS (other
   /// platforms won't be supported in current setup).
   Future<void> stopImageStream() async {
-    assert(defaultTargetPlatform == TargetPlatform.android ||
-        defaultTargetPlatform == TargetPlatform.iOS);
+    assert(defaultTargetPlatform == TargetPlatform.android || defaultTargetPlatform == TargetPlatform.iOS);
 
     if (!value.isInitialized || _isDisposed) {
       throw CameraException(
@@ -571,10 +575,8 @@ class CameraController extends ValueNotifier<CameraValue> {
 
   /// Sets the exposure point for automatically determining the exposure value.
   Future<void> setExposurePoint(Offset point) async {
-    if (point != null &&
-        (point.dx < 0 || point.dx > 1 || point.dy < 0 || point.dy > 1)) {
-      throw ArgumentError(
-          'The values of point should be anywhere between (0,0) and (1,1).');
+    if (point != null && (point.dx < 0 || point.dx > 1 || point.dy < 0 || point.dy > 1)) {
+      throw ArgumentError('The values of point should be anywhere between (0,0) and (1,1).');
     }
     try {
       await CameraPlatform.instance.setExposurePoint(
@@ -661,8 +663,7 @@ class CameraController extends ValueNotifier<CameraValue> {
     }
 
     // Check if offset is in range
-    List<double> range =
-        await Future.wait([getMinExposureOffset(), getMaxExposureOffset()]);
+    List<double> range = await Future.wait([getMinExposureOffset(), getMaxExposureOffset()]);
     if (offset < range[0] || offset > range[1]) {
       throw CameraException(
         "exposureOffsetOutOfBounds",
@@ -696,6 +697,7 @@ class CameraController extends ValueNotifier<CameraValue> {
     if (_isDisposed) {
       return;
     }
+    unawaited(_deviceOrientationSubscription?.cancel());
     _isDisposed = true;
     super.dispose();
     if (_initCalled != null) {

packages/camera/camera/lib/src/camera_preview.dart

@@ -6,6 +6,7 @@ import 'package:camera/camera.dart';
 import 'package:camera_platform_interface/camera_platform_interface.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 
 /// A widget showing a live camera preview.
 class CameraPreview extends StatelessWidget {
@@ -21,18 +22,35 @@ class CameraPreview extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return controller.value.isInitialized
-        ? RotatedBox(
-            quarterTurns: _getQuarterTurns(),
-            child: AspectRatio(
-              aspectRatio: 1 / controller.value.aspectRatio,
-              child: CameraPlatform.instance.buildPreview(controller.cameraId),
-            ),
-          )
+        ? AspectRatio(
+          aspectRatio: _isLandscape() ? controller.value.aspectRatio : (1 / controller.value.aspectRatio),
+          child: Stack(
+            fit: StackFit.expand,
+            children: [
+              RotatedBox(
+                quarterTurns: _getQuarterTurns(),
+                child: CameraPlatform.instance.buildPreview(controller.cameraId),
+              ),
+              child ?? Container(),
+            ],
+          ),
+        )
         : Container();
   }
 
+  bool _isLandscape() {
+    return [DeviceOrientation.landscapeLeft, DeviceOrientation.landscapeRight]
+        .contains(controller.value.deviceOrientation);
+  }
+
   int _getQuarterTurns() {
     int platformOffset = defaultTargetPlatform == TargetPlatform.iOS ? 1 : 0;
-    return platformOffset;
+    Map<DeviceOrientation, int> turns = {
+      DeviceOrientation.portraitUp: 0,
+      DeviceOrientation.portraitDown: 2,
+      DeviceOrientation.landscapeRight: 3,
+      DeviceOrientation.landscapeLeft: 1
+    };
+    return turns[controller.value.deviceOrientation] + platformOffset;
   }
 }

packages/camera/camera/pubspec.yaml

@@ -8,7 +8,9 @@ homepage: https://github.com/flutter/plugins/tree/master/packages/camera/camera
 dependencies:
   flutter:
     sdk: flutter
-  camera_platform_interface: ^1.2.0
+  # TODO (BeMacized): Change back to version reference when the platform interface updates have been published.
+  camera_platform_interface:
+    path: ../camera_platform_interface
   pedantic: ^1.8.0
 
 dev_dependencies: