Sample Flutter App to Take Camera Picture
January 19, 2025
Taking a pic through a mobile camera is a very common phenomenon. In this topic, we would see how to implement a camera app in Flutter. Let’s start on it.
pubspec.yaml dependencies
version: 1.0.0+1
environment:
sdk: ^3.6.0
# Dependencies specify other packages that your package needs in order to work.
# To automatically upgrade your package dependencies to the latest versions
# consider running `flutter pub upgrade --major-versions`. Alternatively,
# dependencies can be manually updated by changing the version numbers below to
# the latest version available on pub.dev. To see which dependencies have newer
# versions available, run `flutter pub outdated`.
dependencies:
flutter:
sdk: flutter
camera: ^0.11.0+2
path_provider: ^2.1.3
permission_handler: ^11.3.1
# The following adds the Cupertino Icons font to your application.
# Use with the CupertinoIcons class for iOS style icons.
cupertino_icons: ^1.0.8
dev_dependencies:
flutter_test:
sdk: flutter
# The "flutter_lints" package below contains a set of recommended lints to
# encourage good coding practices. The lint set provided by the package is
# activated in the `analysis_options.yaml` file located at the root of your
# package. See that file for information about deactivating specific lint
# rules and activating additional ones.
flutter_lints: ^5.0.0
# For information on the generic Dart part of this file, see the
# following page: https://dart.dev/tools/pub/pubspec
# The following section is specific to Flutter packages.
flutter:
# The following line ensures that the Material Icons font is
# included with your application, so that you can use the icons in
# the material Icons class.
uses-material-design: true
Androidmanifest.xml File
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"
/>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE_CAMERA"/>
<application
android:label="abcflutter"
android:name="${applicationName}"
android:icon="@mipmap/ic_launcher">
<activity
android:name=".MainActivity"
android:exported="true"
android:launchMode="singleTop"
android:taskAffinity=""
android:theme="@style/LaunchTheme"
android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
android:hardwareAccelerated="true"
android:windowSoftInputMode="adjustResize">
<!-- Specifies an Android theme to apply to this Activity as soon as
the Android process has started. This theme is visible to the user
while the Flutter UI initializes. After that, this theme continues
to determine the Window background behind the Flutter UI. -->
<meta-data
android:name="io.flutter.embedding.android.NormalTheme"
android:resource="@style/NormalTheme"
/>
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<!-- Don't delete the meta-data below.
This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
<meta-data
android:name="flutterEmbedding"
android:value="2" />
</application>
<!-- Required to query activities that can process text, see:
https://developer.android.com/training/package-visibility and
https://developer.android.com/reference/android/content/Intent#ACTION_PROCESS_TEXT.
In particular, this is used by the Flutter engine in io.flutter.plugin.text.ProcessTextPlugin. -->
<queries>
<intent>
<action android:name="android.intent.action.PROCESS_TEXT"/>
<data android:mimeType="text/plain"/>
</intent>
</queries>
</manifest>
Main.dart
import 'dart:async';
import 'dart:io';
import 'package:camera/camera.dart';
import 'package:flutter/material.dart';
Future<void> main() async {
// Ensure that plugin services are initialized so that `availableCameras()`
// can be called before `runApp()`
WidgetsFlutterBinding.ensureInitialized();
// Obtain a list of the available cameras on the device.
final cameras = await availableCameras();
// Get a specific camera from the list of available cameras.
final firstCamera = cameras.first;
runApp(
MaterialApp(
theme: ThemeData.dark(),
home: TakePictureScreen(
// Pass the appropriate camera to the TakePictureScreen widget.
camera: firstCamera,
),
),
);
}
// A screen that allows users to take a picture using a given camera.
class TakePictureScreen extends StatefulWidget {
const TakePictureScreen({
super.key,
required this.camera,
});
final CameraDescription camera;
@override
TakePictureScreenState createState() => TakePictureScreenState();
}
class TakePictureScreenState extends State<TakePictureScreen> {
late CameraController _controller;
late Future<void> _initializeControllerFuture;
@override
void initState() {
super.initState();
// To display the current output from the Camera,
// create a CameraController.
_controller = CameraController(
// Get a specific camera from the list of available cameras.
widget.camera,
// Define the resolution to use.
ResolutionPreset.medium,
);
// Next, initialize the controller. This returns a Future.
_initializeControllerFuture = _controller.initialize();
}
@override
void dispose() {
// Dispose of the controller when the widget is disposed.
_controller.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Take a picture')),
// You must wait until the controller is initialized before displaying the
// camera preview. Use a FutureBuilder to display a loading spinner until the
// controller has finished initializing.
body: FutureBuilder<void>(
future: _initializeControllerFuture,
builder: (context, snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
// If the Future is complete, display the preview.
return CameraPreview(_controller);
} else {
// Otherwise, display a loading indicator.
return const Center(child: CircularProgressIndicator());
}
},
),
floatingActionButton: FloatingActionButton(
// Provide an onPressed callback.
onPressed: () async {
// Take the Picture in a try / catch block. If anything goes wrong,
// catch the error.
try {
// Ensure that the camera is initialized.
await _initializeControllerFuture;
// Attempt to take a picture and get the file `image`
// where it was saved.
final image = await _controller.takePicture();
if (!context.mounted) return;
// If the picture was taken, display it on a new screen.
await Navigator.of(context).push(
MaterialPageRoute(
builder: (context) => DisplayPictureScreen(
// Pass the automatically generated path to
// the DisplayPictureScreen widget.
imagePath: image.path,
),
),
);
} catch (e) {
// If an error occurs, log the error to the console.
print(e);
}
},
child: const Icon(Icons.camera_alt),
),
);
}
}
// A widget that displays the picture taken by the user.
class DisplayPictureScreen extends StatelessWidget {
final String imagePath;
const DisplayPictureScreen({super.key, required this.imagePath});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Display the Picture')),
// The image is stored as a file on the device. Use the `Image.file`
// constructor with the given path to display the image.
body: Image.file(File(imagePath)),
);
}
}