ML-58 Metering UX improvements (#63)

* indicate EV value error

* allow nullable ev100 in `CameraContainerBloc`

* log exif keys

* wip

* removed `UserPreferencesService` from `MeteringBloc`

* added error toast

* conflicts

* lints

* allow stop metering if `hasError`

* fixed `AnimatedDialogPicker` inability to close

* Update build.gradle

.vscode/launch.json

@@ -8,7 +8,6 @@
             "name": "dev (android)",
             "request": "launch",
             "type": "dart",
-            //"flutterMode": "profile",
             "args": [
                 "--flavor",
                 "dev",
@@ -21,7 +20,6 @@
             "name": "dev (ios)",
             "request": "launch",
             "type": "dart",
-            //"flutterMode": "release",
             "args": [
                 "--flavor",
                 "dev",

android/app/build.gradle

@@ -8,7 +8,7 @@ if (localPropertiesFile.exists()) {
 
 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.")
+    throw GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
 }
 
 def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
@@ -33,6 +33,10 @@ apply plugin: 'com.google.firebase.crashlytics'
 apply plugin: 'kotlin-android'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
+gradle.beforeProject({ project->
+    project.setProperty("target-platform", "android-arm,android-arm64")
+})
+
 android {
     compileSdkVersion 33
     ndkVersion flutter.ndkVersion
@@ -53,8 +57,7 @@ android {
     defaultConfig {
         minSdkVersion 21
         targetSdkVersion 33
-        ndk.abiFilters 'arm64-v8a', 'armeabi-v7a'
+        ndk.abiFilters 'armeabi-v7a', 'arm64-v8a'
-        targetSdkVersion flutter.targetSdkVersion
         /// legacy material-lightmeter ap stopped updating after 60022
         /// 7xxxx means that it is a new app
         versionCode 70000 + flutterVersionCode.toInteger()
@@ -92,7 +95,7 @@ android {
             signingConfig signingConfigs.release
             minifyEnabled true
             shrinkResources true
-            ndk.abiFilters 'arm64-v8a', 'armeabi-v7a'
+            ndk.abiFilters 'armeabi-v7a', 'arm64-v8a'
         }
     }
 }

android/build.gradle

@@ -28,6 +28,6 @@ subprojects {
     project.evaluationDependsOn(':app')
 }
 
-task clean(type: Delete) {
+tasks.register("clean", Delete) {
     delete rootProject.buildDir
 }

lib/data/haptics_service.dart

@@ -7,9 +7,11 @@ class HapticsService {
 
   Future<void> responseVibration() async => _tryVibrate(duration: 50, amplitude: 128);
 
+  Future<void> errorVibration() async => _tryVibrate(duration: 100, amplitude: 128);
+
   Future<void> _tryVibrate({required int duration, required int amplitude}) async {
     if (await _canVibrate()) {
-      Vibration.vibrate(
+      await Vibration.vibrate(
         duration: duration,
         amplitude: amplitude,
       );

lib/interactors/metering_interactor.dart

@@ -4,8 +4,10 @@ import 'package:app_settings/app_settings.dart';
 import 'package:lightmeter/data/caffeine_service.dart';
 import 'package:lightmeter/data/haptics_service.dart';
 import 'package:lightmeter/data/light_sensor_service.dart';
+import 'package:lightmeter/data/models/film.dart';
 import 'package:lightmeter/data/permissions_service.dart';
 import 'package:lightmeter/data/shared_prefs_service.dart';
+import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 import 'package:permission_handler/permission_handler.dart';
 
 class MeteringInteractor {
@@ -30,16 +32,28 @@ class MeteringInteractor {
   double get cameraEvCalibration => _userPreferencesService.cameraEvCalibration;
   double get lightSensorEvCalibration => _userPreferencesService.lightSensorEvCalibration;
 
-  bool get isHapticsEnabled => _userPreferencesService.haptics;
+  IsoValue get iso => _userPreferencesService.iso;
+  set iso(IsoValue value) => _userPreferencesService.iso = value;
+
+  NdValue get ndFilter => _userPreferencesService.ndFilter;
+  set ndFilter(NdValue value) => _userPreferencesService.ndFilter = value;
+
+  Film get film => _userPreferencesService.film;
+  set film(Film value) => _userPreferencesService.film = value;
 
   /// Executes vibration if haptics are enabled in settings
-  void quickVibration() {
+  Future<void> quickVibration() async {
-    if (_userPreferencesService.haptics) _hapticsService.quickVibration();
+    if (_userPreferencesService.haptics) await _hapticsService.quickVibration();
   }
 
   /// Executes vibration if haptics are enabled in settings
-  void responseVibration() {
+  Future<void> responseVibration() async {
-    if (_userPreferencesService.haptics) _hapticsService.responseVibration();
+    if (_userPreferencesService.haptics) await _hapticsService.responseVibration();
+  }
+
+  /// Executes vibration if haptics are enabled in settings
+  Future<void> errorVibration() async {
+    if (_userPreferencesService.haptics) await _hapticsService.errorVibration();
   }
 
   Future<bool> checkCameraPermission() async {

lib/screens/metering/bloc_metering.dart

@@ -4,7 +4,6 @@ import 'dart:math';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:lightmeter/data/models/exposure_pair.dart';
 import 'package:lightmeter/data/models/film.dart';
-import 'package:lightmeter/data/shared_prefs_service.dart';
 import 'package:lightmeter/interactors/metering_interactor.dart';
 import 'package:lightmeter/screens/metering/communication/bloc_communication_metering.dart';
 import 'package:lightmeter/screens/metering/communication/event_communication_metering.dart'
@@ -17,7 +16,6 @@ import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 
 class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   final MeteringCommunicationBloc _communicationBloc;
-  final UserPreferencesService _userPreferencesService;
   final MeteringInteractor _meteringInteractor;
   late final StreamSubscription<communication_states.ScreenState> _communicationSubscription;
 
@@ -29,25 +27,25 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   EquipmentProfileData _equipmentProfileData;
   StopType stopType;
 
-  late IsoValue _iso = _userPreferencesService.iso;
+  late IsoValue _iso = _meteringInteractor.iso;
-  late NdValue _nd = _userPreferencesService.ndFilter;
+  late NdValue _nd = _meteringInteractor.ndFilter;
-  late Film _film = _userPreferencesService.film;
+  late Film _film = _meteringInteractor.film;
-  double _ev100 = 0.0;
+  double? _ev100 = 0.0;
   bool _isMeteringInProgress = false;
 
   MeteringBloc(
     this._communicationBloc,
-    this._userPreferencesService,
     this._meteringInteractor,
     this._equipmentProfileData,
     this.stopType,
   ) : super(
-          MeteringEndedState(
+          MeteringDataState(
             ev: 0.0,
-            film: _userPreferencesService.film,
+            film: _meteringInteractor.film,
-            iso: _userPreferencesService.iso,
+            iso: _meteringInteractor.iso,
-            nd: _userPreferencesService.ndFilter,
+            nd: _meteringInteractor.ndFilter,
             exposurePairs: const [],
+            continuousMetering: false,
           ),
         ) {
     _communicationSubscription = _communicationBloc.stream
@@ -62,6 +60,7 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
     on<NdChangedEvent>(_onNdChanged);
     on<MeasureEvent>(_onMeasure);
     on<MeasuredEvent>(_onMeasured);
+    on<MeasureErrorEvent>(_onMeasureError);
   }
 
   @override
@@ -73,13 +72,13 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   void _onCommunicationState(communication_states.ScreenState communicationState) {
     if (communicationState is communication_states.MeasuredState) {
       _isMeteringInProgress = communicationState is communication_states.MeteringInProgressState;
-      add(MeasuredEvent(communicationState.ev100));
+      _handleEv100(communicationState.ev100);
     }
   }
 
   void _onStopTypeChanged(StopTypeChangedEvent event, Emitter emit) {
     stopType = event.stopType;
-    _emitMeasuredState(emit);
+    _updateMeasurements();
   }
 
   void _onEquipmentProfileChanged(EquipmentProfileChangedEvent event, Emitter emit) {
@@ -88,17 +87,17 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
     /// Update selected ISO value, if selected equipment profile
     /// doesn't contain currently selected value
     if (!event.equipmentProfileData.isoValues.any((v) => _iso.value == v.value)) {
-      _userPreferencesService.iso = event.equipmentProfileData.isoValues.first;
+      _meteringInteractor.iso = event.equipmentProfileData.isoValues.first;
       _iso = event.equipmentProfileData.isoValues.first;
     }
 
     /// The same for ND filter
     if (!event.equipmentProfileData.ndValues.any((v) => _nd.value == v.value)) {
-      _userPreferencesService.ndFilter = event.equipmentProfileData.ndValues.first;
+      _meteringInteractor.ndFilter = event.equipmentProfileData.ndValues.first;
       _nd = event.equipmentProfileData.ndValues.first;
     }
 
-    _emitMeasuredState(emit);
+    _updateMeasurements();
   }
 
   void _onFilmChanged(FilmChangedEvent event, Emitter emit) {
@@ -110,56 +109,76 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
       add(IsoChangedEvent(newIso));
     }
     _film = event.data;
-    _userPreferencesService.film = event.data;
+    _meteringInteractor.film = event.data;
-    _emitMeasuredState(emit);
+    _updateMeasurements();
   }
 
   void _onIsoChanged(IsoChangedEvent event, Emitter emit) {
     if (event.isoValue.value != _film.iso) {
       _film = Film.values.first;
     }
-    _userPreferencesService.iso = event.isoValue;
+    _meteringInteractor.iso = event.isoValue;
     _iso = event.isoValue;
-    _emitMeasuredState(emit);
+    _updateMeasurements();
   }
 
   void _onNdChanged(NdChangedEvent event, Emitter emit) {
-    _userPreferencesService.ndFilter = event.ndValue;
+    _meteringInteractor.ndFilter = event.ndValue;
     _nd = event.ndValue;
-    _emitMeasuredState(emit);
+    _updateMeasurements();
   }
 
-  void _onMeasure(_, Emitter emit) {
+  void _onMeasure(MeasureEvent _, Emitter emit) {
     _meteringInteractor.quickVibration();
     _communicationBloc.add(const communication_events.MeasureEvent());
     _isMeteringInProgress = true;
-    emit(const LoadingState());
+    emit(
+      LoadingState(
+        film: _film,
+        iso: _iso,
+        nd: _nd,
+      ),
+    );
+  }
+
+  void _updateMeasurements() => _handleEv100(_ev100);
+
+  void _handleEv100(double? ev100) {
+    if (ev100 == null || ev100.isNaN || ev100.isInfinite) {
+      add(const MeasureErrorEvent());
+    } else {
+      add(MeasuredEvent(ev100));
+    }
   }
 
   void _onMeasured(MeasuredEvent event, Emitter emit) {
     _meteringInteractor.responseVibration();
     _ev100 = event.ev100;
-    _emitMeasuredState(emit);
+    final ev = event.ev100 + log2(_iso.value / 100) - _nd.stopReduction;
+    emit(
+      MeteringDataState(
+        ev: ev,
+        film: _film,
+        iso: _iso,
+        nd: _nd,
+        exposurePairs: _buildExposureValues(ev),
+        continuousMetering: _isMeteringInProgress,
+      ),
+    );
   }
 
-  void _emitMeasuredState(Emitter emit) {
+  void _onMeasureError(MeasureErrorEvent _, Emitter emit) {
-    final ev = _ev100 + log2(_iso.value / 100) - _nd.stopReduction;
+    _meteringInteractor.errorVibration();
+    _ev100 = null;
     emit(
-      _isMeteringInProgress
+      MeteringDataState(
-          ? MeteringInProgressState(
+        ev: null,
-              ev: ev,
+        film: _film,
-              film: _film,
+        iso: _iso,
-              iso: _iso,
+        nd: _nd,
-              nd: _nd,
+        exposurePairs: const [],
-              exposurePairs: _buildExposureValues(ev),
+        continuousMetering: _isMeteringInProgress,
-            )
+      ),
-          : MeteringEndedState(
-              ev: ev,
-              film: _film,
-              iso: _iso,
-              nd: _nd,
-              exposurePairs: _buildExposureValues(ev),
-            ),
     );
   }
 

lib/screens/metering/communication/event_communication_metering.dart

@@ -15,7 +15,7 @@ class MeasureEvent extends ScreenEvent {
 }
 
 abstract class MeasuredEvent extends SourceEvent {
-  final double ev100;
+  final double? ev100;
 
   const MeasuredEvent(this.ev100);
 }

lib/screens/metering/communication/state_communication_metering.dart

@@ -19,7 +19,7 @@ class MeasureState extends SourceState {
 }
 
 abstract class MeasuredState extends ScreenState {
-  final double ev100;
+  final double? ev100;
 
   const MeasuredState(this.ev100);
 }

lib/screens/metering/components/bottom_controls/components/measure_button/widget_button_measure.dart

@@ -6,11 +6,13 @@ import 'package:lightmeter/screens/shared/filled_circle/widget_circle_filled.dar
 class MeteringMeasureButton extends StatefulWidget {
   final double? ev;
   final bool isMetering;
+  final bool hasError;
   final VoidCallback onTap;
 
   const MeteringMeasureButton({
     required this.ev,
     required this.isMetering,
+    required this.hasError,
     required this.onTap,
     super.key,
   });
@@ -33,7 +35,7 @@ class _MeteringMeasureButtonState extends State<MeteringMeasureButton> {
   @override
   Widget build(BuildContext context) {
     return IgnorePointer(
-      ignoring: widget.isMetering && widget.ev == null,
+      ignoring: widget.isMetering && widget.ev == null && !widget.hasError,
       child: GestureDetector(
         onTap: widget.onTap,
         onTapDown: (_) {
@@ -63,7 +65,13 @@ class _MeteringMeasureButtonState extends State<MeteringMeasureButton> {
                     color: Theme.of(context).colorScheme.onSurface,
                     size: Dimens.grid72 - Dimens.grid8,
                     child: Center(
-                      child: widget.ev != null ? _EvValueText(ev: widget.ev!) : null,
+                      child: widget.hasError
+                          ? Icon(
+                              Icons.error_outline,
+                              color: Theme.of(context).colorScheme.surface,
+                              size: Dimens.grid24,
+                            )
+                          : (widget.ev != null ? _EvValueText(ev: widget.ev!) : null),
                     ),
                   ),
                 ),
@@ -91,13 +99,6 @@ class _EvValueText extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    if (ev.isNaN || ev.isInfinite) {
-      return Icon(
-        Icons.error,
-        color: Theme.of(context).colorScheme.surface,
-      );
-    }
-
     final theme = Theme.of(context);
     return Text(
       '${ev.toStringAsFixed(1)}\n${S.of(context).ev}',

lib/screens/metering/components/bottom_controls/provider_bottom_controls.dart

@@ -6,6 +6,7 @@ import 'package:lightmeter/screens/metering/components/bottom_controls/widget_bo
 class MeteringBottomControlsProvider extends StatelessWidget {
   final double? ev;
   final bool isMetering;
+  final bool hasError;
   final VoidCallback? onSwitchEvSourceType;
   final VoidCallback onMeasure;
   final VoidCallback onSettings;
@@ -13,6 +14,7 @@ class MeteringBottomControlsProvider extends StatelessWidget {
   const MeteringBottomControlsProvider({
     required this.ev,
     required this.isMetering,
+    required this.hasError,
     required this.onSwitchEvSourceType,
     required this.onMeasure,
     required this.onSettings,
@@ -36,6 +38,7 @@ class MeteringBottomControlsProvider extends StatelessWidget {
       child: MeteringBottomControls(
         ev: ev,
         isMetering: isMetering,
+        hasError: hasError,
         onSwitchEvSourceType: onSwitchEvSourceType,
         onMeasure: onMeasure,
         onSettings: onSettings,

lib/screens/metering/components/bottom_controls/widget_bottom_controls.dart

@@ -7,6 +7,7 @@ import 'package:provider/provider.dart';
 class MeteringBottomControls extends StatelessWidget {
   final double? ev;
   final bool isMetering;
+  final bool hasError;
   final VoidCallback? onSwitchEvSourceType;
   final VoidCallback onMeasure;
   final VoidCallback onSettings;
@@ -14,6 +15,7 @@ class MeteringBottomControls extends StatelessWidget {
   const MeteringBottomControls({
     required this.ev,
     required this.isMetering,
+    required this.hasError,
     required this.onSwitchEvSourceType,
     required this.onMeasure,
     required this.onSettings,
@@ -54,6 +56,7 @@ class MeteringBottomControls extends StatelessWidget {
                 MeteringMeasureButton(
                   ev: ev,
                   isMetering: isMetering,
+                  hasError: hasError,
                   onTap: onMeasure,
                 ),
                 Expanded(

lib/screens/metering/components/camera_container/bloc_container_camera.dart

@@ -1,6 +1,7 @@
 import 'dart:async';
+import 'dart:developer';
 import 'dart:io';
-import 'dart:math';
+import 'dart:math' as math;
 import 'dart:typed_data';
 
 import 'package:camera/camera.dart';
@@ -34,7 +35,7 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
   double _exposureStep = 0.0;
   double _currentExposureOffset = 0.0;
 
-  double _ev100 = 0.0;
+  double? _ev100 = 0.0;
 
   CameraContainerBloc(
     this._meteringInteractor,
@@ -67,12 +68,17 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
   @override
   void onCommunicationState(communication_states.SourceState communicationState) {
     if (communicationState is communication_states.MeasureState) {
-      _takePhoto().then((ev100Raw) {
+      if (_canTakePhoto) {
-        if (ev100Raw != null) {
+        _takePhoto().then((ev100Raw) {
-          _ev100 = ev100Raw + _meteringInteractor.cameraEvCalibration;
+          if (ev100Raw != null) {
-          communicationBloc.add(communication_event.MeteringEndedEvent(_ev100));
+            _ev100 = ev100Raw + _meteringInteractor.cameraEvCalibration;
-        }
+            communicationBloc.add(communication_event.MeteringEndedEvent(_ev100));
-      });
+          } else {
+            _ev100 = null;
+            communicationBloc.add(const communication_event.MeteringEndedEvent(null));
+          }
+        });
+      }
     }
   }
 
@@ -118,7 +124,7 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
       _zoomRange = await Future.wait<double>([
         _cameraController!.getMinZoomLevel(),
         _cameraController!.getMaxZoomLevel(),
-      ]).then((levels) => RangeValues(levels[0], min(_maxZoom, levels[1])));
+      ]).then((levels) => RangeValues(levels[0], math.min(_maxZoom, levels[1])));
       _currentZoom = _zoomRange!.start;
 
       _exposureOffsetRange = await Future.wait<double>([
@@ -126,8 +132,8 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
         _cameraController!.getMaxExposureOffset(),
       ]).then(
         (levels) => RangeValues(
-          max(_exposureMaxRange.start, levels[0]),
+          math.max(_exposureMaxRange.start, levels[0]),
-          min(_exposureMaxRange.end, levels[1]),
+          math.min(_exposureMaxRange.end, levels[1]),
         ),
       );
       await _cameraController!.getExposureOffsetStepSize().then((value) {
@@ -172,28 +178,31 @@ class CameraContainerBloc extends EvSourceBlocBase<CameraContainerEvent, CameraC
     );
   }
 
-  Future<double?> _takePhoto() async {
+  bool get _canTakePhoto => !(_cameraController == null ||
-    if (_cameraController == null ||
+      !_cameraController!.value.isInitialized ||
-        !_cameraController!.value.isInitialized ||
+      _cameraController!.value.isTakingPicture);
-        _cameraController!.value.isTakingPicture) {
-      return null;
-    }
 
+  Future<double?> _takePhoto() async {
     try {
       final file = await _cameraController!.takePicture();
       final Uint8List bytes = await file.readAsBytes();
       Directory(file.path).deleteSync(recursive: true);
 
       final tags = await readExifFromBytes(bytes);
-      final iso = double.parse("${tags["EXIF ISOSpeedRatings"]}");
+      final iso = double.tryParse("${tags["EXIF ISOSpeedRatings"]}");
-      final apertureValueRatio = (tags["EXIF FNumber"]!.values as IfdRatios).ratios.first;
+      final apertureValueRatio = (tags["EXIF FNumber"]?.values as IfdRatios?)?.ratios.first;
+      final speedValueRatio = (tags["EXIF ExposureTime"]?.values as IfdRatios?)?.ratios.first;
+      if (iso == null || apertureValueRatio == null || speedValueRatio == null) {
+        log('Error parsing EXIF: ${tags.keys}');
+        return null;
+      }
+
       final aperture = apertureValueRatio.numerator / apertureValueRatio.denominator;
-      final speedValueRatio = (tags["EXIF ExposureTime"]!.values as IfdRatios).ratios.first;
       final speed = speedValueRatio.numerator / speedValueRatio.denominator;
 
-      return log2(pow(aperture, 2)) - log2(speed) - log2(iso / 100);
+      return log2(math.pow(aperture, 2)) - log2(speed) - log2(iso / 100);
     } on CameraException catch (e) {
-      debugPrint('Error: ${e.code}\nError Message: ${e.description}');
+      log('Error: ${e.code}\nError Message: ${e.description}');
       return null;
     }
   }

lib/screens/metering/components/shared/readings_container/components/animated_dialog_picker/widget_picker_dialog_animated.dart

@@ -3,8 +3,9 @@ import 'package:flutter/material.dart';
 import 'package:lightmeter/screens/metering/components/shared/readings_container/components/animated_dialog_picker/components/animated_dialog/widget_dialog_animated.dart';
 import 'package:lightmeter/screens/metering/components/shared/readings_container/components/animated_dialog_picker/components/dialog_picker/widget_picker_dialog.dart';
 
-class AnimatedDialogPicker<T> extends StatelessWidget {
+// Has to be stateful, so that [GlobalKey] is not recreated. 
-  final _key = GlobalKey<AnimatedDialogState>();
+// Otherwise use will no be able to close the dialog after EV value has changed.
+class AnimatedDialogPicker<T> extends StatefulWidget {
   final IconData icon;
   final String title;
   final String? subtitle;
@@ -15,7 +16,7 @@ class AnimatedDialogPicker<T> extends StatelessWidget {
   final ValueChanged<T> onChanged;
   final Widget closedChild;
 
-  AnimatedDialogPicker({
+  const AnimatedDialogPicker({
     required this.icon,
     required this.title,
     this.subtitle,
@@ -28,24 +29,31 @@ class AnimatedDialogPicker<T> extends StatelessWidget {
     super.key,
   });
 
+  @override
+  State<AnimatedDialogPicker<T>> createState() => _AnimatedDialogPickerState<T>();
+}
+
+class _AnimatedDialogPickerState<T> extends State<AnimatedDialogPicker<T>> {
+  final _key = GlobalKey<AnimatedDialogState>();
+
   @override
   Widget build(BuildContext context) {
     return AnimatedDialog(
       key: _key,
-      closedChild: closedChild,
+      closedChild: widget.closedChild,
       openedChild: DialogPicker<T>(
-        icon: icon,
+        icon: widget.icon,
-        title: title,
+        title: widget.title,
-        subtitle: subtitle,
+        subtitle: widget.subtitle,
-        initialValue: selectedValue,
+        initialValue: widget.selectedValue,
-        values: values,
+        values: widget.values,
-        itemTitleBuilder: itemTitleBuilder,
+        itemTitleBuilder: widget.itemTitleBuilder,
-        itemTrailingBuilder: itemTrailingBuilder,
+        itemTrailingBuilder: widget.itemTrailingBuilder,
         onCancel: () {
           _key.currentState?.close();
         },
         onSelect: (value) {
-          _key.currentState?.close().then((_) => onChanged(value));
+          _key.currentState?.close().then((_) => widget.onChanged(value));
         },
       ),
     );

lib/screens/metering/components/shared/readings_container/widget_container_readings.dart

@@ -11,7 +11,6 @@ import 'package:lightmeter/screens/metering/components/shared/readings_container
 import 'package:lightmeter/screens/metering/components/shared/readings_container/components/reading_value_container/widget_container_reading_value.dart';
 import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 
-/// Contains a column of fastest & slowest exposure pairs + a row of ISO and ND pickers
 class ReadingsContainer extends StatelessWidget {
   final ExposurePair? fastest;
   final ExposurePair? slowest;

lib/screens/metering/event_metering.dart

@@ -44,3 +44,7 @@ class MeasuredEvent extends MeteringEvent {
 
   const MeasuredEvent(this.ev100);
 }
+
+class MeasureErrorEvent extends MeteringEvent {
+  const MeasureErrorEvent();
+}

lib/screens/metering/flow_metering.dart

@@ -37,7 +37,6 @@ class _MeteringFlowState extends State<MeteringFlow> {
           BlocProvider(
             create: (context) => MeteringBloc(
               context.read<MeteringCommunicationBloc>(),
-              context.read<UserPreferencesService>(),
               context.read<MeteringInteractor>(),
               EquipmentProfile.of(context, listen: false),
               context.read<StopType>(),

lib/screens/metering/screen_metering.dart

@@ -44,26 +44,25 @@ class _MeteringScreenState extends State<MeteringScreen> {
         children: [
           Expanded(
             child: BlocBuilder<MeteringBloc, MeteringState>(
-              buildWhen: (_, current) => current is MeteringDataState,
+              builder: (_, state) => _MeteringContainerBuidler(
-              builder: (_, state) => state is MeteringDataState
+                fastest: state is MeteringDataState ? state.fastest : null,
-                  ? _MeteringContainerBuidler(
+                slowest: state is MeteringDataState ? state.slowest : null,
-                      fastest: state.fastest,
+                exposurePairs: state is MeteringDataState ? state.exposurePairs : [],
-                      slowest: state.slowest,
+                film: state.film,
-                      film: state.film,
+                iso: state.iso,
-                      iso: state.iso,
+                nd: state.nd,
-                      nd: state.nd,
+                onFilmChanged: (value) => _bloc.add(FilmChangedEvent(value)),
-                      onFilmChanged: (value) => _bloc.add(FilmChangedEvent(value)),
+                onIsoChanged: (value) => _bloc.add(IsoChangedEvent(value)),
-                      onIsoChanged: (value) => _bloc.add(IsoChangedEvent(value)),
+                onNdChanged: (value) => _bloc.add(NdChangedEvent(value)),
-                      onNdChanged: (value) => _bloc.add(NdChangedEvent(value)),
+              ),
-                      exposurePairs: state.exposurePairs,
-                    )
-                  : const SizedBox.shrink(),
             ),
           ),
           BlocBuilder<MeteringBloc, MeteringState>(
             builder: (context, state) => MeteringBottomControlsProvider(
               ev: state is MeteringDataState ? state.ev : null,
-              isMetering: state is LoadingState || state is MeteringInProgressState,
+              isMetering:
+                  state is LoadingState || state is MeteringDataState && state.continuousMetering,
+              hasError: state is MeteringDataState && state.hasError,
               onSwitchEvSourceType: context.read<Environment>().hasLightSensor
                   ? EvSourceTypeProvider.of(context).toggleType
                   : null,

lib/screens/metering/state_metering.dart

@@ -5,48 +5,40 @@ import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 
 @immutable
 abstract class MeteringState {
-  const MeteringState();
-}
-
-class LoadingState extends MeteringState {
-  const LoadingState();
-}
-
-abstract class MeteringDataState extends MeteringState {
-  final double ev;
   final Film film;
   final IsoValue iso;
   final NdValue nd;
-  final List<ExposurePair> exposurePairs;
 
-  const MeteringDataState({
+  const MeteringState({
-    required this.ev,
     required this.film,
     required this.iso,
     required this.nd,
+  });
+}
+
+class LoadingState extends MeteringState {
+  const LoadingState({
+    required super.film,
+    required super.iso,
+    required super.nd,
+  });
+}
+
+class MeteringDataState extends MeteringState {
+  final double? ev;
+  final List<ExposurePair> exposurePairs;
+  final bool continuousMetering;
+
+  const MeteringDataState({
+    required this.ev,
+    required super.film,
+    required super.iso,
+    required super.nd,
     required this.exposurePairs,
+    required this.continuousMetering,
   });
 
   ExposurePair? get fastest => exposurePairs.isEmpty ? null : exposurePairs.first;
   ExposurePair? get slowest => exposurePairs.isEmpty ? null : exposurePairs.last;
-}
+  bool get hasError => ev == null;
-
-class MeteringInProgressState extends MeteringDataState {
-  const MeteringInProgressState({
-    required super.ev,
-    required super.film,
-    required super.iso,
-    required super.nd,
-    required super.exposurePairs,
-  });
-}
-
-class MeteringEndedState extends MeteringDataState {
-  const MeteringEndedState({
-    required super.ev,
-    required super.film,
-    required super.iso,
-    required super.nd,
-    required super.exposurePairs,
-  });
 }

pubspec.yaml

@@ -27,7 +27,7 @@ dependencies:
       url: "https://github.com/vodemn/m3_lightmeter_resources"
       ref: main
   material_color_utilities: 0.2.0
-  package_info_plus: 3.0.2
+  package_info_plus: 4.0.0
   permission_handler: 10.2.0
   provider: 6.0.4
   shared_preferences: 2.0.15