配置根项目“imagepicker”时出现问题：未找到 SDK

Question

在 Android Studio 中（在 Flutter 项目中），我试图让 imagepicker 插件正常工作，但我不断收到此错误：

FAILURE: Build failed with an exception.


* What went wrong:
A problem occurred configuring root project 'imagepicker'.
> SDK location not found. Define location with sdk.dir in the local.properties file or with an ANDROID_HOME environment variable.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 2s

Finished with error: The plugin image_picker could not be built due to the issue above.

我已经阅读了一些关于此错误的主题。但是我试图更改local.properties 文件，我更新了yaml 文件，我更新了gradle 文件，插件被导入... 有谁知道如何解决这个问题？我只是再也看不到树木了

Main.dart：

import 'package:flutter/material.dart';    
import 'components/Page.dart';
import 'package:flutter/foundation.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget{
  @override
  Widget build(BuildContext context){
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new Page(title: 'Title'),
      );
  }
}

Page.dart：

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

class Page extends StatefulWidget {
  Page({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _PageState createState() => new _PageState();
}

class _PageState extends State<Page> {
  int number = 0;
  File image;

  takePicture() async {
    print('Take picture called');
    File img = await ImagePicker.pickImage(source: ImageSource.camera);
    if (img != null) {
      image = img;
      setState(() {});
    }
  }

  chooseFromGallery() async {
    print('Choose from gallery called');
    File img = await ImagePicker.pickImage(source: ImageSource.gallery);
    if (img != null) {
      image = img;
      setState(() {});
    }
  }

  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
        home: new Scaffold(
            appBar: new AppBar(
              title: new Text("Raised Button"),
            ),
            body: new Container(
              child: new Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  new Container(
                    child: image == null
                        ? new Text('No Image to Show')
                        : new Image.file(image),
                    height: 300,
                    width: 300,
                    color: Color.fromARGB(0, 50, 20, 20),
                  ),
                  new Row(
                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                    children: <Widget>[
                      new RaisedButton(
                        padding: const EdgeInsets.all(8.0),
                        textColor: Colors.black,
                        color: Colors.white,
                        onPressed: takePicture,
                        child: new Icon(Icons.camera_alt),
                      ),
                      new RaisedButton(
                        onPressed: chooseFromGallery,
                        textColor: Colors.black,
                        color: Colors.white,
                        padding: const EdgeInsets.all(8.0),
                        child: new Icon(Icons.attach_file),
                      ),
                    ],
                  )
                ],
              ),
            )));
  }
}

app\build.gradle：

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

android {
    compileSdkVersion 28

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.example.jsontest"
        minSdkVersion 16
        targetSdkVersion 28
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
}

Android\build.gradle：

buildscript {
    ext.kotlin_version = '1.3.50'
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:3.2.0'

    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

pubspec.yaml：

name: jsontest
description: A new Flutter application.

# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1

environment:
  sdk: ">=2.1.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  http: any
  test:
  image_picker: ^0.4.10

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.2

dev_dependencies:
  flutter_test:
    sdk: flutter




# 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.
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

  # To add assets to your application, add an assets section, like this:
  # assets:
  #  - images/a_dot_burr.jpeg
  #  - images/a_dot_ham.jpeg

  # An image asset can refer to one or more resolution-specific "variants", see
  # https://flutter.dev/assets-and-images/#resolution-aware.

  # For details regarding adding assets from package dependencies, see
  # https://flutter.dev/assets-and-images/#from-packages

  # To add custom fonts to your application, add a fonts section here,
  # in this "flutter" section. Each entry in this list should have a
  # "family" key with the font family name, and a "fonts" key with a
  # list giving the asset and other descriptors for the font. For
  # example:
  # fonts:
  #   - family: Schyler
  #     fonts:
  #       - asset: fonts/Schyler-Regular.ttf
  #       - asset: fonts/Schyler-Italic.ttf
  #         style: italic
  #   - family: Trajan Pro
  #     fonts:
  #       - asset: fonts/TrajanPro.ttf
  #       - asset: fonts/TrajanPro_Bold.ttf
  #         weight: 700
  #
  # For details regarding fonts from package dependencies,
  # see https://flutter.dev/custom-fonts/#from-packages

local.properties：

sdk.dir=C\:...\\Android\\sdk
flutter.sdk=C\:...\\flutter
flutter.buildMode=debug
flutter.versionName=1.0.0
flutter.versionCode=1

Answer 1

您使用旧版本的 image_picker 是否有原因？如果不是最新版本是image_picker: ^0.6.4，然后只需按照pub.dev 的自述文件下的设置说明进行操作。使用新版本设置图像选择器非常容易，唯一需要的设置是向 info.plist 添加几个条目