uvccamera 0.0.7

A USB Video Class (UVC) camera plugin for Flutter based on UVCCamera library for Android.

example/example.md

UVCCamera Example

The example demonstrates how to use the UVCCamera plugin in a Flutter app. \n## pubspec.yaml\n\n```yaml\nname: uvccamera_example description: "Demonstrates how to use the uvccamera plugin." publish_to: none

environment: sdk: ^3.5.4

dependencies: flutter: sdk: flutter uvccamera: 0.0.7 cross_file: ^0.3.4+2 cupertino_icons: ^1.0.8 permission_handler: ^11.3.1

dev_dependencies: integration_test: sdk: flutter flutter_test: sdk: flutter flutter_lints: ^5.0.0

flutter: uses-material-design: true \n\n## [lib/main.dart](https://github.com/alexey-pelykh/UVCCamera/blob/main/flutter/example/lib/main.dart)\n\ndart\nimport 'package:flutter/material.dart';

import 'uvccamera_demo_app.dart';

void main() { WidgetsFlutterBinding.ensureInitialized();

runApp(const UvcCameraDemoApp()); } \n\n## [lib/uvccamera_demo_app.dart](https://github.com/alexey-pelykh/UVCCamera/blob/main/flutter/example/lib/uvccamera_demo_app.dart)\n\ndart\nimport 'package:flutter/material.dart';

import 'uvccamera_devices_screen.dart';

class UvcCameraDemoApp extends StatefulWidget { const UvcCameraDemoApp({super.key});

@override State

class _UvcCameraDemoAppState extends State

import 'uvccamera_widget.dart';

class UvcCameraDeviceScreen extends StatelessWidget { final UvcCameraDevice device;

const UvcCameraDeviceScreen({super.key, required this.device});

@override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text(device.name), ), body: Center( child: UvcCameraWidget(device: device), ), ); } } \n\n## [lib/uvccamera_devices_screen.dart](https://github.com/alexey-pelykh/UVCCamera/blob/main/flutter/example/lib/uvccamera_devices_screen.dart)\n\ndart\nimport 'dart:async';

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

import 'uvccamera_device_screen.dart';

class UvcCameraDevicesScreen extends StatefulWidget { const UvcCameraDevicesScreen({super.key});

@override State

class _UvcCameraDevicesScreenState extends State

@override void initState() { super.initState();

UvcCamera.isSupported().then((value) {
  setState(() {
    _isSupported = value;
  });
});

_deviceEventSubscription = UvcCamera.deviceEventStream.listen((event) {
  setState(() {
    if (event.type == UvcCameraDeviceEventType.attached) {
      _devices[event.device.name] = event.device;
    } else if (event.type == UvcCameraDeviceEventType.detached) {
      _devices.remove(event.device.name);
    }
  });
});

UvcCamera.getDevices().then((devices) {
  setState(() {
    _devices.addAll(devices);
  });
});

}

@override void dispose() { _deviceEventSubscription?.cancel(); _deviceEventSubscription = null;

super.dispose();

}

@override Widget build(BuildContext context) { if (!_isSupported) { return const Center( child: Text( 'UVC Camera is not supported on this device.', style: TextStyle(fontSize: 18), ), ); }

if (_devices.isEmpty) {
  return const Center(
    child: Text(
      'No UVC devices connected.',
      style: TextStyle(fontSize: 18),
    ),
  );
}

return ListView(
  children: _devices.values.map((device) {
    return ListTile(
      leading: const Icon(Icons.videocam),
      title: Text(device.name),
      subtitle: Text('Vendor ID: ${device.vendorId}, Product ID: ${device.productId}'),
      onTap: () {
        Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => UvcCameraDeviceScreen(device: device),
          ),
        );
      },
    );
  }).toList(),
);

} } \n\n## [lib/uvccamera_widget.dart](https://github.com/alexey-pelykh/UVCCamera/blob/main/flutter/example/lib/uvccamera_widget.dart)\n\ndart\nimport 'dart:async';

import 'package:cross_file/cross_file.dart'; import 'package:flutter/material.dart'; import 'package:permission_handler/permission_handler.dart'; import 'package:uvccamera/uvccamera.dart';

class UvcCameraWidget extends StatefulWidget { final UvcCameraDevice device;

const UvcCameraWidget({super.key, required this.device});

@override State

class _UvcCameraWidgetState extends State

@override void initState() { super.initState();

UvcCamera.getDevices().then((devices) {
  if (!devices.containsKey(widget.device.name)) {
    return;
  }

  setState(() {
    _isDeviceAttached = true;
  });

  _requestPermissions();
});

_deviceEventSubscription = UvcCamera.deviceEventStream.listen((event) {
  if (event.device.name != widget.device.name) {
    return;
  }

  if (event.type == UvcCameraDeviceEventType.attached && !_isDeviceAttached) {
    // NOTE: Requesting UVC device permission will trigger connection request
    _requestPermissions();
  }

  setState(() {
    if (event.type == UvcCameraDeviceEventType.attached) {
      // _hasCameraPermission - maybe
      // _hasDevicePermission - maybe
      _isDeviceAttached = true;
      _isDeviceConnected = false;
    } else if (event.type == UvcCameraDeviceEventType.detached) {
      _hasCameraPermission = false;
      _hasDevicePermission = false;
      _isDeviceAttached = false;
      _isDeviceConnected = false;
    } else if (event.type == UvcCameraDeviceEventType.connected) {
      _hasCameraPermission = true;
      _hasDevicePermission = true;
      _isDeviceAttached = true;
      _isDeviceConnected = true;

      _log = '';

      _cameraController = UvcCameraController(
        device: widget.device,
      );
      _cameraControllerInitializeFuture = _cameraController!.initialize().then((_) async {
        _statusEventSubscription = _cameraController!.cameraStatusEvents.listen((event) {
          setState(() {
            _log = 'status: ${event.payload}\n$_log';
          });
        });

        _buttonEventSubscription = _cameraController!.cameraButtonEvents.listen((event) {
          setState(() {
            _log = 'btn(${event.button}): ${event.state}\n$_log';
          });
        });
      });
    } else if (event.type == UvcCameraDeviceEventType.disconnected) {
      _hasCameraPermission = false;
      _hasDevicePermission = false;
      // _isDeviceAttached - maybe?
      _isDeviceConnected = false;

      _buttonEventSubscription?.cancel();
      _buttonEventSubscription = null;

      _statusEventSubscription?.cancel();
      _statusEventSubscription = null;

      _cameraController?.dispose();
      _cameraController = null;
      _cameraControllerInitializeFuture = null;

      _log = '';
    }
  });
});

}

@override void dispose() { _cameraController?.dispose(); _cameraController = null;

_deviceEventSubscription?.cancel();
_deviceEventSubscription = null;

super.dispose();

}

Future

  return value;
});

// NOTE: Requesting UVC device permission can be made only after camera permission is granted
if (!hasCameraPermission) {
  return;
}

_requestDevicePermission().then((value) {
  setState(() {
    _hasDevicePermission = value;
  });

  return value;
});

}

Future

Future

Future

Future

outputFile.length().then((length) {
  setState(() {
    _log = 'image file: ${outputFile.path} ($length bytes)\n$_log';
  });
});

}

Future

outputFile.length().then((length) {
  setState(() {
    _log = 'video file: ${outputFile.path} ($length bytes)\n$_log';
  });
});

}

@override Widget build(BuildContext context) { if (!_isDeviceAttached) { return Center( child: Text( 'Device is not attached', style: TextStyle(fontSize: 18), ), ); }

if (!_hasCameraPermission) {
  return Center(
    child: Text(
      'Camera permission is not granted',
      style: TextStyle(fontSize: 18),
    ),
  );
}

if (!_hasDevicePermission) {
  return Center(
    child: Text(
      'Device permission is not granted',
      style: TextStyle(fontSize: 18),
    ),
  );
}

if (!_isDeviceConnected) {
  return Center(
    child: Text(
      'Device is not connected',
      style: TextStyle(fontSize: 18),
    ),
  );
}

return FutureBuilder<void>(
  future: _cameraControllerInitializeFuture,
  builder: (context, snapshot) {
    if (snapshot.connectionState == ConnectionState.done) {
      return Stack(
        children: [
          UvcCameraPreview(
            _cameraController!,
            child: Padding(
              padding: const EdgeInsets.all(8.0),
              child: SingleChildScrollView(
                child: SelectableText(
                  _log,
                  style: TextStyle(
                    color: Colors.red,
                    fontFamily: 'Courier',
                    fontSize: 10.0,
                  ),
                ),
              ),
            ),
          ),
          Align(
            alignment: Alignment.bottomCenter,
            child: Padding(
              padding: const EdgeInsets.only(bottom: 50.0),
              child: ValueListenableBuilder<UvcCameraControllerState>(
                valueListenable: _cameraController!,
                builder: (context, value, child) {
                  return Row(
                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                    children: [
                      FloatingActionButton(
                        backgroundColor: Colors.white,
                        onPressed: () async => {
                          await _takePicture(),
                        },
                        child: Icon(Icons.camera_alt, color: Colors.black),
                      ),
                      FloatingActionButton(
                        backgroundColor: value.isRecordingVideo ? Colors.red : Colors.white,
                        onPressed: () async {
                          if (value.isRecordingVideo) {
                            await _stopVideoRecording();
                          } else {
                            await _startVideoRecording(value.previewMode!);
                          }
                        },
                        child: Icon(
                          value.isRecordingVideo ? Icons.stop : Icons.videocam,
                          color: value.isRecordingVideo ? Colors.white : Colors.black,
                        ),
                      ),
                    ],
                  );
                },
              ),
            ),
          ),
        ],
      );
    } else {
      return const Center(child: CircularProgressIndicator());
    }
  },
);

} }