A Flutter Plugin for Controlling The Camera

Camera Plugin

A Flutter plugin for iOS, Android and Web allowing access to the device cameras.

Features

• Display live camera preview in a widget.
• Snapshots can be captured and saved to a file.
• Record video.
• Add access to the image stream from Dart.

Installation

First, add camera as a dependency in your pubspec.yaml file.

iOS

Add two rows to the ios/Runner/Info.plist:

• one with the key Privacy - Camera Usage Description and a usage description.
• and one with the key Privacy - Microphone Usage Description and a usage description.

If editing Info.plist as text, add:

<key>NSCameraUsageDescription</key>
<string>your usage description here</string>
<key>NSMicrophoneUsageDescription</key>
<string>your usage description here</string>

Android

Change the minimum Android sdk version to 21 (or higher) in your android/app/build.gradle file.

minSdkVersion 21

It's important to note that the MediaRecorder class is not working properly on emulators, as stated in the documentation: https://developer.android.com/reference/android/media/MediaRecorder. Specifically, when recording a video with sound enabled and trying to play it back, the duration won't be correct and you will only see the first frame.

Web integration

For web integration details, see the camera_web package.

Handling Lifecycle states

As of version 0.5.0 of the camera plugin, lifecycle changes are no longer handled by the plugin. This means developers are now responsible to control camera resources when the lifecycle state is updated. Failure to do so might lead to unexpected behavior (for example as described in issue #39109). Handling lifecycle changes can be done by overriding the didChangeAppLifecycleState method like so:

@override
void didChangeAppLifecycleState(AppLifecycleState state) {
  final CameraController? cameraController = controller;

  // App state changed before we got the chance to initialize.
  if (cameraController == null || !cameraController.value.isInitialized) {
    return;
  }

  if (state == AppLifecycleState.inactive) {
    cameraController.dispose();
  } else if (state == AppLifecycleState.resumed) {
    _initializeCameraController(cameraController.description);
  }
}

Handling camera access permissions

Permission errors may be thrown when initializing the camera controller, and you are expected to handle them properly.

Here is a list of all permission error codes that can be thrown:

CameraAccessDenied: Thrown when user denies the camera access permission.

CameraAccessDeniedWithoutPrompt: iOS only for now. Thrown when user has previously denied the permission. iOS does not allow prompting alert dialog a second time. Users will have to go to Settings > Privacy > Camera in order to enable camera access.

CameraAccessRestricted: iOS only for now. Thrown when camera access is restricted and users cannot grant permission (parental control).

AudioAccessDenied: Thrown when user denies the audio access permission.

AudioAccessDeniedWithoutPrompt: iOS only for now. Thrown when user has previously denied the permission. iOS does not allow prompting alert dialog a second time. Users will have to go to Settings > Privacy > Microphone in order to enable audio access.

AudioAccessRestricted: iOS only for now. Thrown when audio access is restricted and users cannot grant permission (parental control).

Example

Here is a small example flutter app displaying a full screen camera preview.

import 'package:camera/camera.dart';
import 'package:flutter/material.dart';

late List<CameraDescription> _cameras;

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();

  _cameras = await availableCameras();
  runApp(const CameraApp());
}

/// CameraApp is the Main Application.
class CameraApp extends StatefulWidget {
  /// Default Constructor
  const CameraApp({super.key});

  @override
  State<CameraApp> createState() => _CameraAppState();
}

class _CameraAppState extends State<CameraApp> {
  late CameraController controller;

  @override
  void initState() {
    super.initState();
    controller = CameraController(_cameras[0], ResolutionPreset.max);
    controller.initialize().then((_) {
      if (!mounted) {
        return;
      }
      setState(() {});
    }).catchError((Object e) {
      if (e is CameraException) {
        switch (e.code) {
          case 'CameraAccessDenied':
            // Handle access errors here.
            break;
          default:
            // Handle other errors here.
            break;
        }
      }
    });
  }

  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    if (!controller.value.isInitialized) {
      return Container();
    }
    return MaterialApp(
      home: CameraPreview(controller),
    );
  }
}

For a more elaborate usage example see here.

Use this package as a library

Depend on it

Run this command:

With Flutter:

 $ flutter pub add camera

This will add a line like this to your package's pubspec.yaml (and run an implicit flutter pub get):

dependencies:
  camera: ^0.10.5+2

Alternatively, your editor might support flutter pub get. Check the docs for your editor to learn more.

Import it

Now in your Dart code, you can use:

import 'package:camera/camera.dart'; 

example/lib/main.dart

// Copyright 2013 The Flutter 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 'dart:io';

import 'package:camera/camera.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart';
import 'package:video_player/video_player.dart';

/// Camera example home widget.
class CameraExampleHome extends StatefulWidget {
  /// Default Constructor
  const CameraExampleHome({super.key});

  @override
  State<CameraExampleHome> createState() {
    return _CameraExampleHomeState();
  }
}

/// Returns a suitable camera icon for [direction].
IconData getCameraLensIcon(CameraLensDirection direction) {
  switch (direction) {
    case CameraLensDirection.back:
      return Icons.camera_rear;
    case CameraLensDirection.front:
      return Icons.camera_front;
    case CameraLensDirection.external:
      return Icons.camera;
  }
  // This enum is from a different package, so a new value could be added at
  // any time. The example should keep working if that happens.
  // ignore: dead_code
  return Icons.camera;
}

void _logError(String code, String? message) {
  // ignore: avoid_print
  print('Error: $code${message == null ? '' : '\nError Message: $message'}');
}

class _CameraExampleHomeState extends State<CameraExampleHome>
    with WidgetsBindingObserver, TickerProviderStateMixin {
  CameraController? controller;
  XFile? imageFile;
  XFile? videoFile;
  VideoPlayerController? videoController;
  VoidCallback? videoPlayerListener;
  bool enableAudio = true;
  double _minAvailableExposureOffset = 0.0;
  double _maxAvailableExposureOffset = 0.0;
  double _currentExposureOffset = 0.0;
  late AnimationController _flashModeControlRowAnimationController;
  late Animation<double> _flashModeControlRowAnimation;
  late AnimationController _exposureModeControlRowAnimationController;
  late Animation<double> _exposureModeControlRowAnimation;
  late AnimationController _focusModeControlRowAnimationController;
  late Animation<double> _focusModeControlRowAnimation;
  double _minAvailableZoom = 1.0;
  double _maxAvailableZoom = 1.0;
  double _currentScale = 1.0;
  double _baseScale = 1.0;

  // Counting pointers (number of user fingers on screen)
  int _pointers = 0;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);

    _flashModeControlRowAnimationController = AnimationController(
      duration: const Duration(milliseconds: 300),
      vsync: this,
    );
    _flashModeControlRowAnimation = CurvedAnimation(
      parent: _flashModeControlRowAnimationController,
      curve: Curves.easeInCubic,
    );
    _exposureModeControlRowAnimationController = AnimationController(
      duration: const Duration(milliseconds: 300),
      vsync: this,
    );
    _exposureModeControlRowAnimation = CurvedAnimation(
      parent: _exposureModeControlRowAnimationController,
      curve: Curves.easeInCubic,
    );
    _focusModeControlRowAnimationController = AnimationController(
      duration: const Duration(milliseconds: 300),
      vsync: this,
    );
    _focusModeControlRowAnimation = CurvedAnimation(
      parent: _focusModeControlRowAnimationController,
      curve: Curves.easeInCubic,
    );
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    _flashModeControlRowAnimationController.dispose();
    _exposureModeControlRowAnimationController.dispose();
    super.dispose();
  }

  // #docregion AppLifecycle
  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    final CameraController? cameraController = controller;

    // App state changed before we got the chance to initialize.
    if (cameraController == null || !cameraController.value.isInitialized) {
      return;
    }

    if (state == AppLifecycleState.inactive) {
      cameraController.dispose();
    } else if (state == AppLifecycleState.resumed) {
      _initializeCameraController(cameraController.description);
    }
  }
  // #enddocregion AppLifecycle

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Camera example'),
      ),
      body: Column(
        children: <Widget>[
          Expanded(
            child: Container(
              decoration: BoxDecoration(
                color: Colors.black,
                border: Border.all(
                  color:
                      controller != null && controller!.value.isRecordingVideo
                          ? Colors.redAccent
                          : Colors.grey,
                  width: 3.0,
                ),
              ),
              child: Padding(
                padding: const EdgeInsets.all(1.0),
                child: Center(
                  child: _cameraPreviewWidget(),
                ),
              ),
            ),
          ),
          _captureControlRowWidget(),
          _modeControlRowWidget(),
          Padding(
            padding: const EdgeInsets.all(5.0),
            child: Row(
              children: <Widget>[
                _cameraTogglesRowWidget(),
                _thumbnailWidget(),
              ],
            ),
          ),
        ],
      ),
    );
  }

  /// Display the preview from the camera (or a message if the preview is not available).
  Widget _cameraPreviewWidget() {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isInitialized) {
      return const Text(
        'Tap a camera',
        style: TextStyle(
          color: Colors.white,
          fontSize: 24.0,
          fontWeight: FontWeight.w900,
        ),
      );
    } else {
      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: (TapDownDetails details) =>
                  onViewFinderTap(details, constraints),
            );
          }),
        ),
      );
    }
  }

  void _handleScaleStart(ScaleStartDetails details) {
    _baseScale = _currentScale;
  }

  Future<void> _handleScaleUpdate(ScaleUpdateDetails details) async {
    // When there are not exactly two fingers on screen don't scale
    if (controller == null || _pointers != 2) {
      return;
    }

    _currentScale = (_baseScale * details.scale)
        .clamp(_minAvailableZoom, _maxAvailableZoom);

    await controller!.setZoomLevel(_currentScale);
  }

  /// Display the thumbnail of the captured image or video.
  Widget _thumbnailWidget() {
    final VideoPlayerController? localVideoController = videoController;

    return Expanded(
      child: Align(
        alignment: Alignment.centerRight,
        child: Row(
          mainAxisSize: MainAxisSize.min,
          children: <Widget>[
            if (localVideoController == null && imageFile == null)
              Container()
            else
              SizedBox(
                width: 64.0,
                height: 64.0,
                child: (localVideoController == null)
                    ? (
                        // The captured image on the web contains a network-accessible URL
                        // pointing to a location within the browser. It may be displayed
                        // either with Image.network or Image.memory after loading the image
                        // bytes to memory.
                        kIsWeb
                            ? Image.network(imageFile!.path)
                            : Image.file(File(imageFile!.path)))
                    : Container(
                        decoration: BoxDecoration(
                            border: Border.all(color: Colors.pink)),
                        child: Center(
                          child: AspectRatio(
                              aspectRatio:
                                  localVideoController.value.aspectRatio,
                              child: VideoPlayer(localVideoController)),
                        ),
                      ),
              ),
          ],
        ),
      ),
    );
  }

  /// Display a bar with buttons to change the flash and exposure modes
  Widget _modeControlRowWidget() {
    return Column(
      children: <Widget>[
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: <Widget>[
            IconButton(
              icon: const Icon(Icons.flash_on),
              color: Colors.blue,
              onPressed: controller != null ? onFlashModeButtonPressed : null,
            ),
            // The exposure and focus mode are currently not supported on the web.
            ...!kIsWeb
                ? <Widget>[
                    IconButton(
                      icon: const Icon(Icons.exposure),
                      color: Colors.blue,
                      onPressed: controller != null
                          ? onExposureModeButtonPressed
                          : null,
                    ),
                    IconButton(
                      icon: const Icon(Icons.filter_center_focus),
                      color: Colors.blue,
                      onPressed:
                          controller != null ? onFocusModeButtonPressed : null,
                    )
                  ]
                : <Widget>[],
            IconButton(
              icon: Icon(enableAudio ? Icons.volume_up : Icons.volume_mute),
              color: Colors.blue,
              onPressed: controller != null ? onAudioModeButtonPressed : null,
            ),
            IconButton(
              icon: Icon(controller?.value.isCaptureOrientationLocked ?? false
                  ? Icons.screen_lock_rotation
                  : Icons.screen_rotation),
              color: Colors.blue,
              onPressed: controller != null
                  ? onCaptureOrientationLockButtonPressed
                  : null,
            ),
          ],
        ),
        _flashModeControlRowWidget(),
        _exposureModeControlRowWidget(),
        _focusModeControlRowWidget(),
      ],
    );
  }

  Widget _flashModeControlRowWidget() {
    return SizeTransition(
      sizeFactor: _flashModeControlRowAnimation,
      child: ClipRect(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: <Widget>[
            IconButton(
              icon: const Icon(Icons.flash_off),
              color: controller?.value.flashMode == FlashMode.off
                  ? Colors.orange
                  : Colors.blue,
              onPressed: controller != null
                  ? () => onSetFlashModeButtonPressed(FlashMode.off)
                  : null,
            ),
            IconButton(
              icon: const Icon(Icons.flash_auto),
              color: controller?.value.flashMode == FlashMode.auto
                  ? Colors.orange
                  : Colors.blue,
              onPressed: controller != null
                  ? () => onSetFlashModeButtonPressed(FlashMode.auto)
                  : null,
            ),
            IconButton(
              icon: const Icon(Icons.flash_on),
              color: controller?.value.flashMode == FlashMode.always
                  ? Colors.orange
                  : Colors.blue,
              onPressed: controller != null
                  ? () => onSetFlashModeButtonPressed(FlashMode.always)
                  : null,
            ),
            IconButton(
              icon: const Icon(Icons.highlight),
              color: controller?.value.flashMode == FlashMode.torch
                  ? Colors.orange
                  : Colors.blue,
              onPressed: controller != null
                  ? () => onSetFlashModeButtonPressed(FlashMode.torch)
                  : null,
            ),
          ],
        ),
      ),
    );
  }

  Widget _exposureModeControlRowWidget() {
    final ButtonStyle styleAuto = TextButton.styleFrom(
      // TODO(darrenaustin): Migrate to new API once it lands in stable: https://github.com/flutter/flutter/issues/105724
      // ignore: deprecated_member_use
      primary: controller?.value.exposureMode == ExposureMode.auto
          ? Colors.orange
          : Colors.blue,
    );
    final ButtonStyle styleLocked = TextButton.styleFrom(
      // TODO(darrenaustin): Migrate to new API once it lands in stable: https://github.com/flutter/flutter/issues/105724
      // ignore: deprecated_member_use
      primary: controller?.value.exposureMode == ExposureMode.locked
          ? Colors.orange
          : Colors.blue,
    );

    return SizeTransition(
      sizeFactor: _exposureModeControlRowAnimation,
      child: ClipRect(
        child: Container(
          color: Colors.grey.shade50,
          child: Column(
            children: <Widget>[
              const Center(
                child: Text('Exposure Mode'),
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                children: <Widget>[
                  TextButton(
                    style: styleAuto,
                    onPressed: controller != null
                        ? () =>
                            onSetExposureModeButtonPressed(ExposureMode.auto)
                        : null,
                    onLongPress: () {
                      if (controller != null) {
                        controller!.setExposurePoint(null);
                        showInSnackBar('Resetting exposure point');
                      }
                    },
                    child: const Text('AUTO'),
                  ),
                  TextButton(
                    style: styleLocked,
                    onPressed: controller != null
                        ? () =>
                            onSetExposureModeButtonPressed(ExposureMode.locked)
                        : null,
                    child: const Text('LOCKED'),
                  ),
                  TextButton(
                    style: styleLocked,
                    onPressed: controller != null
                        ? () => controller!.setExposureOffset(0.0)
                        : null,
                    child: const Text('RESET OFFSET'),
                  ),
                ],
              ),
              const Center(
                child: Text('Exposure Offset'),
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                children: <Widget>[
                  Text(_minAvailableExposureOffset.toString()),
                  Slider(
                    value: _currentExposureOffset,
                    min: _minAvailableExposureOffset,
                    max: _maxAvailableExposureOffset,
                    label: _currentExposureOffset.toString(),
                    onChanged: _minAvailableExposureOffset ==
                            _maxAvailableExposureOffset
                        ? null
                        : setExposureOffset,
                  ),
                  Text(_maxAvailableExposureOffset.toString()),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _focusModeControlRowWidget() {
    final ButtonStyle styleAuto = TextButton.styleFrom(
      // TODO(darrenaustin): Migrate to new API once it lands in stable: https://github.com/flutter/flutter/issues/105724
      // ignore: deprecated_member_use
      primary: controller?.value.focusMode == FocusMode.auto
          ? Colors.orange
          : Colors.blue,
    );
    final ButtonStyle styleLocked = TextButton.styleFrom(
      // TODO(darrenaustin): Migrate to new API once it lands in stable: https://github.com/flutter/flutter/issues/105724
      // ignore: deprecated_member_use
      primary: controller?.value.focusMode == FocusMode.locked
          ? Colors.orange
          : Colors.blue,
    );

    return SizeTransition(
      sizeFactor: _focusModeControlRowAnimation,
      child: ClipRect(
        child: Container(
          color: Colors.grey.shade50,
          child: Column(
            children: <Widget>[
              const Center(
                child: Text('Focus Mode'),
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                children: <Widget>[
                  TextButton(
                    style: styleAuto,
                    onPressed: controller != null
                        ? () => onSetFocusModeButtonPressed(FocusMode.auto)
                        : null,
                    onLongPress: () {
                      if (controller != null) {
                        controller!.setFocusPoint(null);
                      }
                      showInSnackBar('Resetting focus point');
                    },
                    child: const Text('AUTO'),
                  ),
                  TextButton(
                    style: styleLocked,
                    onPressed: controller != null
                        ? () => onSetFocusModeButtonPressed(FocusMode.locked)
                        : null,
                    child: const Text('LOCKED'),
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }

  /// Display the control bar with buttons to take pictures and record videos.
  Widget _captureControlRowWidget() {
    final CameraController? cameraController = controller;

    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
      children: <Widget>[
        IconButton(
          icon: const Icon(Icons.camera_alt),
          color: Colors.blue,
          onPressed: cameraController != null &&
                  cameraController.value.isInitialized &&
                  !cameraController.value.isRecordingVideo
              ? onTakePictureButtonPressed
              : null,
        ),
        IconButton(
          icon: const Icon(Icons.videocam),
          color: Colors.blue,
          onPressed: cameraController != null &&
                  cameraController.value.isInitialized &&
                  !cameraController.value.isRecordingVideo
              ? onVideoRecordButtonPressed
              : null,
        ),
        IconButton(
          icon: cameraController != null &&
                  cameraController.value.isRecordingPaused
              ? const Icon(Icons.play_arrow)
              : const Icon(Icons.pause),
          color: Colors.blue,
          onPressed: cameraController != null &&
                  cameraController.value.isInitialized &&
                  cameraController.value.isRecordingVideo
              ? (cameraController.value.isRecordingPaused)
                  ? onResumeButtonPressed
                  : onPauseButtonPressed
              : null,
        ),
        IconButton(
          icon: const Icon(Icons.stop),
          color: Colors.red,
          onPressed: cameraController != null &&
                  cameraController.value.isInitialized &&
                  cameraController.value.isRecordingVideo
              ? onStopButtonPressed
              : null,
        ),
        IconButton(
          icon: const Icon(Icons.pause_presentation),
          color:
              cameraController != null && cameraController.value.isPreviewPaused
                  ? Colors.red
                  : Colors.blue,
          onPressed:
              cameraController == null ? null : onPausePreviewButtonPressed,
        ),
      ],
    );
  }

  /// Display a row of toggle to select the camera (or a message if no camera is available).
  Widget _cameraTogglesRowWidget() {
    final List<Widget> toggles = <Widget>[];

    void onChanged(CameraDescription? description) {
      if (description == null) {
        return;
      }

      onNewCameraSelected(description);
    }

    if (_cameras.isEmpty) {
      SchedulerBinding.instance.addPostFrameCallback((_) async {
        showInSnackBar('No camera found.');
      });
      return const Text('None');
    } else {
      for (final CameraDescription cameraDescription in _cameras) {
        toggles.add(
          SizedBox(
            width: 90.0,
            child: RadioListTile<CameraDescription>(
              title: Icon(getCameraLensIcon(cameraDescription.lensDirection)),
              groupValue: controller?.description,
              value: cameraDescription,
              onChanged: onChanged,
            ),
          ),
        );
      }
    }

    return Row(children: toggles);
  }

  String timestamp() => DateTime.now().millisecondsSinceEpoch.toString();

  void showInSnackBar(String message) {
    ScaffoldMessenger.of(context)
        .showSnackBar(SnackBar(content: Text(message)));
  }

  void onViewFinderTap(TapDownDetails details, BoxConstraints constraints) {
    if (controller == null) {
      return;
    }

    final CameraController cameraController = controller!;

    final Offset offset = Offset(
      details.localPosition.dx / constraints.maxWidth,
      details.localPosition.dy / constraints.maxHeight,
    );
    cameraController.setExposurePoint(offset);
    cameraController.setFocusPoint(offset);
  }

  Future<void> onNewCameraSelected(CameraDescription cameraDescription) async {
    if (controller != null) {
      return controller!.setDescription(cameraDescription);
    } else {
      return _initializeCameraController(cameraDescription);
    }
  }

  Future<void> _initializeCameraController(
      CameraDescription cameraDescription) async {
    final CameraController cameraController = CameraController(
      cameraDescription,
      kIsWeb ? ResolutionPreset.max : ResolutionPreset.medium,
      enableAudio: enableAudio,
      imageFormatGroup: ImageFormatGroup.jpeg,
    );

    controller = cameraController;

    // If the controller is updated then update the UI.
    cameraController.addListener(() {
      if (mounted) {
        setState(() {});
      }
      if (cameraController.value.hasError) {
        showInSnackBar(
            'Camera error ${cameraController.value.errorDescription}');
      }
    });

    try {
      await cameraController.initialize();
      await Future.wait(<Future<Object?>>[
        // The exposure mode is currently not supported on the web.
        ...!kIsWeb
            ? <Future<Object?>>[
                cameraController.getMinExposureOffset().then(
                    (double value) => _minAvailableExposureOffset = value),
                cameraController
                    .getMaxExposureOffset()
                    .then((double value) => _maxAvailableExposureOffset = value)
              ]
            : <Future<Object?>>[],
        cameraController
            .getMaxZoomLevel()
            .then((double value) => _maxAvailableZoom = value),
        cameraController
            .getMinZoomLevel()
            .then((double value) => _minAvailableZoom = value),
      ]);
    } on CameraException catch (e) {
      switch (e.code) {
        case 'CameraAccessDenied':
          showInSnackBar('You have denied camera access.');
          break;
        case 'CameraAccessDeniedWithoutPrompt':
          // iOS only
          showInSnackBar('Please go to Settings app to enable camera access.');
          break;
        case 'CameraAccessRestricted':
          // iOS only
          showInSnackBar('Camera access is restricted.');
          break;
        case 'AudioAccessDenied':
          showInSnackBar('You have denied audio access.');
          break;
        case 'AudioAccessDeniedWithoutPrompt':
          // iOS only
          showInSnackBar('Please go to Settings app to enable audio access.');
          break;
        case 'AudioAccessRestricted':
          // iOS only
          showInSnackBar('Audio access is restricted.');
          break;
        default:
          _showCameraException(e);
          break;
      }
    }

    if (mounted) {
      setState(() {});
    }
  }

  void onTakePictureButtonPressed() {
    takePicture().then((XFile? file) {
      if (mounted) {
        setState(() {
          imageFile = file;
          videoController?.dispose();
          videoController = null;
        });
        if (file != null) {
          showInSnackBar('Picture saved to ${file.path}');
        }
      }
    });
  }

  void onFlashModeButtonPressed() {
    if (_flashModeControlRowAnimationController.value == 1) {
      _flashModeControlRowAnimationController.reverse();
    } else {
      _flashModeControlRowAnimationController.forward();
      _exposureModeControlRowAnimationController.reverse();
      _focusModeControlRowAnimationController.reverse();
    }
  }

  void onExposureModeButtonPressed() {
    if (_exposureModeControlRowAnimationController.value == 1) {
      _exposureModeControlRowAnimationController.reverse();
    } else {
      _exposureModeControlRowAnimationController.forward();
      _flashModeControlRowAnimationController.reverse();
      _focusModeControlRowAnimationController.reverse();
    }
  }

  void onFocusModeButtonPressed() {
    if (_focusModeControlRowAnimationController.value == 1) {
      _focusModeControlRowAnimationController.reverse();
    } else {
      _focusModeControlRowAnimationController.forward();
      _flashModeControlRowAnimationController.reverse();
      _exposureModeControlRowAnimationController.reverse();
    }
  }

  void onAudioModeButtonPressed() {
    enableAudio = !enableAudio;
    if (controller != null) {
      onNewCameraSelected(controller!.description);
    }
  }

  Future<void> onCaptureOrientationLockButtonPressed() async {
    try {
      if (controller != null) {
        final CameraController cameraController = controller!;
        if (cameraController.value.isCaptureOrientationLocked) {
          await cameraController.unlockCaptureOrientation();
          showInSnackBar('Capture orientation unlocked');
        } else {
          await cameraController.lockCaptureOrientation();
          showInSnackBar(
              'Capture orientation locked to ${cameraController.value.lockedCaptureOrientation.toString().split('.').last}');
        }
      }
    } on CameraException catch (e) {
      _showCameraException(e);
    }
  }

  void onSetFlashModeButtonPressed(FlashMode mode) {
    setFlashMode(mode).then((_) {
      if (mounted) {
        setState(() {});
      }
      showInSnackBar('Flash mode set to ${mode.toString().split('.').last}');
    });
  }

  void onSetExposureModeButtonPressed(ExposureMode mode) {
    setExposureMode(mode).then((_) {
      if (mounted) {
        setState(() {});
      }
      showInSnackBar('Exposure mode set to ${mode.toString().split('.').last}');
    });
  }

  void onSetFocusModeButtonPressed(FocusMode mode) {
    setFocusMode(mode).then((_) {
      if (mounted) {
        setState(() {});
      }
      showInSnackBar('Focus mode set to ${mode.toString().split('.').last}');
    });
  }

  void onVideoRecordButtonPressed() {
    startVideoRecording().then((_) {
      if (mounted) {
        setState(() {});
      }
    });
  }

  void onStopButtonPressed() {
    stopVideoRecording().then((XFile? file) {
      if (mounted) {
        setState(() {});
      }
      if (file != null) {
        showInSnackBar('Video recorded to ${file.path}');
        videoFile = file;
        _startVideoPlayer();
      }
    });
  }

  Future<void> onPausePreviewButtonPressed() async {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isInitialized) {
      showInSnackBar('Error: select a camera first.');
      return;
    }

    if (cameraController.value.isPreviewPaused) {
      await cameraController.resumePreview();
    } else {
      await cameraController.pausePreview();
    }

    if (mounted) {
      setState(() {});
    }
  }

  void onPauseButtonPressed() {
    pauseVideoRecording().then((_) {
      if (mounted) {
        setState(() {});
      }
      showInSnackBar('Video recording paused');
    });
  }

  void onResumeButtonPressed() {
    resumeVideoRecording().then((_) {
      if (mounted) {
        setState(() {});
      }
      showInSnackBar('Video recording resumed');
    });
  }

  Future<void> startVideoRecording() async {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isInitialized) {
      showInSnackBar('Error: select a camera first.');
      return;
    }

    if (cameraController.value.isRecordingVideo) {
      // A recording is already started, do nothing.
      return;
    }

    try {
      await cameraController.startVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      return;
    }
  }

  Future<XFile?> stopVideoRecording() async {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isRecordingVideo) {
      return null;
    }

    try {
      return cameraController.stopVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
  }

  Future<void> pauseVideoRecording() async {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isRecordingVideo) {
      return;
    }

    try {
      await cameraController.pauseVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> resumeVideoRecording() async {
    final CameraController? cameraController = controller;

    if (cameraController == null || !cameraController.value.isRecordingVideo) {
      return;
    }

    try {
      await cameraController.resumeVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> setFlashMode(FlashMode mode) async {
    if (controller == null) {
      return;
    }

    try {
      await controller!.setFlashMode(mode);
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> setExposureMode(ExposureMode mode) async {
    if (controller == null) {
      return;
    }

    try {
      await controller!.setExposureMode(mode);
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> setExposureOffset(double offset) async {
    if (controller == null) {
      return;
    }

    setState(() {
      _currentExposureOffset = offset;
    });
    try {
      offset = await controller!.setExposureOffset(offset);
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> setFocusMode(FocusMode mode) async {
    if (controller == null) {
      return;
    }

    try {
      await controller!.setFocusMode(mode);
    } on CameraException catch (e) {
      _showCameraException(e);
      rethrow;
    }
  }

  Future<void> _startVideoPlayer() async {
    if (videoFile == null) {
      return;
    }

    final VideoPlayerController vController = kIsWeb
        ? VideoPlayerController.network(videoFile!.path)
        : VideoPlayerController.file(File(videoFile!.path));

    videoPlayerListener = () {
      if (videoController != null) {
        // Refreshing the state to update video player with the correct ratio.
        if (mounted) {
          setState(() {});
        }
        videoController!.removeListener(videoPlayerListener!);
      }
    };
    vController.addListener(videoPlayerListener!);
    await vController.setLooping(true);
    await vController.initialize();
    await videoController?.dispose();
    if (mounted) {
      setState(() {
        imageFile = null;
        videoController = vController;
      });
    }
    await vController.play();
  }

  Future<XFile?> takePicture() async {
    final CameraController? cameraController = controller;
    if (cameraController == null || !cameraController.value.isInitialized) {
      showInSnackBar('Error: select a camera first.');
      return null;
    }

    if (cameraController.value.isTakingPicture) {
      // A capture is already pending, do nothing.
      return null;
    }

    try {
      final XFile file = await cameraController.takePicture();
      return file;
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
  }

  void _showCameraException(CameraException e) {
    _logError(e.code, e.description);
    showInSnackBar('Error: ${e.code}\n${e.description}');
  }
}

/// CameraApp is the Main Application.
class CameraApp extends StatelessWidget {
  /// Default Constructor
  const CameraApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: CameraExampleHome(),
    );
  }
}

List<CameraDescription> _cameras = <CameraDescription>[];

Future<void> main() async {
  // Fetch the available cameras before initializing the app.
  try {
    WidgetsFlutterBinding.ensureInitialized();
    _cameras = await availableCameras();
  } on CameraException catch (e) {
    _logError(e.code, e.description);
  }
  runApp(const CameraApp());
}

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Source: https://github.com/flutter/packages/tree/main/packages/camera/camera

#flutter #camera