آموزش انتخاب و ادیت عکس از گالری در فلاتر

dependencies:
flutter:
  sdk: flutter
image_picker: ^0.6.7+6
image_cropper: ^1.3.0

<dict>
  .
  .
  <key>NSPhotoLibraryUsageDescription</key>
  <string>Upload images for screen background</string>
  <key>NSCameraUsageDescription</key>
  <string>Upload image from camera for screen background</string>
  <key>NSMicrophoneUsageDescription</key>
  <string>Post videos to profile</string>
  .
  .
</dict>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   .
   .
    <application
        android:requestLegacyExternalStorage="true"
        android:name="io.flutter.app.FlutterApplication"
        android:label="xxxxxx"
        android:icon="@mipmap/launcher_icon">

        <activity
            android:name="com.yalantis.ucrop.UCropActivity"
            android:screenOrientation="portrait"
            android:theme="@style/Theme.AppCompat.Light.NoActionBar"/>
            .
            .
    </application>
    .
    .
</manifest>

/// Get from gallery
_getFromGallery() async {
    PickedFile pickedFile = await ImagePicker().getImage(
        source: ImageSource.gallery,
        maxWidth: 1800,
        maxHeight: 1800,
    );
    _cropImage(pickedFile.path);
}

/// Crop Image
_cropImage(filePath) async {
    File croppedImage = await ImageCropper.cropImage(
        sourcePath: filePath,
        maxWidth: 1080,
        maxHeight: 1080,
    );
}

Future<Null> _cropImage(filePath) async {
  File croppedImage = await ImageCropper.cropImage(
      sourcePath: filePath,
      maxWidth: 1080,
      maxHeight: 1080,
      aspectRatio: CropAspectRatio(ratioX: 1.0, ratioY: 1.0)
  );
  if (croppedImage  != null) {
      imageFile = croppedImage ;
      setState(() {});
  }
}

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:image_cropper/image_cropper.dart';

class MyPage extends StatefulWidget {
  @override
  _MyPageState createState() => _MyPageState();
}

class _MyPageState extends State<MyPage> {
  /// Variables
  File imageFile;

  /// Widget
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          backgroundColor: Color(0XFF307777),
          title: Text("Image Cropper"),
        ),
        body: Container(
            child: imageFile == null
                ? Container(
                    alignment: Alignment.center,
                    child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: <Widget>[
                        RaisedButton(
                          color: Color(0XFF307777),
                          onPressed: () {
                            _getFromGallery();
                          },
                          child: Text(
                            "PICK FROM GALLERY",
                            style: TextStyle(color: Colors.white),
                          ),
                        ),
                      ],
                    ),
                  )
                : Container(
                    child: Image.file(
                      imageFile,
                      fit: BoxFit.cover,
                    ),
                  )));
  }

  /// Get from gallery
  _getFromGallery() async {
    PickedFile pickedFile = await ImagePicker().getImage(
      source: ImageSource.gallery,
      maxWidth: 1800,
      maxHeight: 1800,
    );
    _cropImage(pickedFile.path);
  }

  /// Crop Image
  _cropImage(filePath) async {
    File croppedImage = await ImageCropper.cropImage(
      sourcePath: filePath,
      maxWidth: 1080,
      maxHeight: 1080,
    );
    if (croppedImage != null) {
      imageFile = croppedImage;
      setState(() {});
    }
  }
}