Надеюсь, это подходящий ответ, как вы хотели.
Запустите этот код:
import 'dart:async';
import 'dart:io';
import 'package:camera/camera.dart';
import 'package:flutter/material.dart';
import 'package:image_cropper/image_cropper.dart';
import 'package:path/path.dart' show join;
import 'package:path_provider/path_provider.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(
MyApp(firstCamera: firstCamera,)
);
}
class MyApp extends StatelessWidget {
final firstCamera;
// This widget is the root of your application.
MyApp({this.firstCamera});
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
// routes: routes,
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 {
final CameraDescription camera;
const TakePictureScreen({
Key key,
@required this.camera,
}) : super(key: key);
@override
TakePictureScreenState createState() => TakePictureScreenState();
}
class TakePictureScreenState extends State<TakePictureScreen> {
CameraController _controller;
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) {
final size = MediaQuery.of(context).size.width;
return Scaffold(
appBar: AppBar(title: Text('Take a picture')),
// 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: Center(
child: Container(
width: size,
height: size,
child: ClipRect(
child: OverflowBox(
alignment: Alignment.center,
child: FittedBox(
fit: BoxFit.fitWidth,
child: Container(
width: size,
height:size,
child: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 Center(child: CircularProgressIndicator());
}
},
),
),
),
),
),
)
),
floatingActionButton: FloatingActionButton(
child: Icon(Icons.camera_alt),
// 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;
// Construct the path where the image should be saved using the
// pattern package.
final path = join(
// Store the picture in the temp directory.
// Find the temp directory using the `path_provider` plugin.
(await getTemporaryDirectory()).path,
'${DateTime.now()}.png',
);
// Attempt to take a picture and log where it's been saved.
await _controller.takePicture(path);
// If the picture was taken, display it on a new screen.
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => DisplayPictureScreen(imagePath: path),
),
);
} catch (e) {
// If an error occurs, log the error to the console.
print(e);
}
},
),
);
}
}
// A widget that displays the picture taken by the user.
class DisplayPictureScreen extends StatefulWidget {
final String imagePath;
const DisplayPictureScreen({Key key, this.imagePath}) : super(key: key);
@override
_DisplayPictureScreenState createState() => _DisplayPictureScreenState();
}
class _DisplayPictureScreenState extends State<DisplayPictureScreen> {
var finalImage ;
@override
void initState() {
super.initState();
croppingImage();
}
croppingImage()async{
File croppedFile = await ImageCropper.cropImage(
sourcePath: File(widget.imagePath).path,
aspectRatioPresets: [
CropAspectRatioPreset.square,
CropAspectRatioPreset.ratio3x2,
CropAspectRatioPreset.original,
CropAspectRatioPreset.ratio4x3,
CropAspectRatioPreset.ratio16x9
],
androidUiSettings: AndroidUiSettings(
toolbarTitle: 'Cropper',
toolbarColor: Colors.pink,
toolbarWidgetColor: Colors.white,
initAspectRatio: CropAspectRatioPreset.original,
lockAspectRatio: false),
iosUiSettings: IOSUiSettings(
minimumAspectRatio: 1.0,
)
);
if(croppedFile!=null){
setState(() {
finalImage = croppedFile;
});
}else{
setState(() {
finalImage = File(widget.imagePath);
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: 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: Center(
child:
finalImage !=null ?
Container(
height: MediaQuery.of(context).size.height/2, //400
// width: MediaQuery.of(context).size.width/1.2,//400
decoration: BoxDecoration(
border: Border.all(color: Colors.red),
image: DecorationImage(
image: FileImage(finalImage),
fit: BoxFit.cover
)
),
)
:Container()
)
);
}
}
Измените с помощью AndroidManifest. xml с этим
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myapp">
<!-- io.flutter.app.FlutterApplication is an android.app.Application that
calls FlutterMain.startInitialization(this); in its onCreate method.
In most cases you can leave this as-is, but you if you want to provide
additional functionality it is fine to subclass or reimplement
FlutterApplication and put your custom class here. -->
<application
android:name="io.flutter.app.FlutterApplication"
android:label="myapp"
android:icon="@mipmap/ic_launcher">
<activity
android:name=".MainActivity"
android:launchMode="singleTop"
android:theme="@style/LaunchTheme"
android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
android:hardwareAccelerated="true"
android:windowSoftInputMode="adjustResize">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<!-Add Crop Activity -->
<!-Add this line -->
<activity
android:name="com.yalantis.ucrop.UCropActivity"
android:screenOrientation="portrait"
android:theme="@style/Theme.AppCompat.Light.NoActionBar"/>
<!-- 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>
</manifest>
Вид камеры в квадратной форме:
Обрезка захваченного изображения перед отображением:
Захваченное изображение в квадрате:
