Flutter问题：“无法解决配置'：classpath'的所有工件，”

Question

我正在尝试运行在设备上编写的Flutter应用程序，但是当我尝试运行时，我从不经过“ assembleDebug”阶段并在终端中收到此消息：

Launching lib\main.dart on SM N950U in debug mode...
Running Gradle task 'assembleDebug'...

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'android'.
> Could not resolve all artifacts for configuration ':classpath'.
   > Could not find com.android.tools.build:gradle:5.6.2.
     Searched in the following locations:
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/5.6.2/gradle-5.6.2.pom
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/5.6.2/gradle-5.6.2.jar
       - https://jcenter.bintray.com/com/android/tools/build/gradle/5.6.2/gradle-5.6.2.pom
       - https://jcenter.bintray.com/com/android/tools/build/gradle/5.6.2/gradle-5.6.2.jar
     Required by:
         project :

* 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 14s
Finished with error: Gradle task assembleDebug failed with exit code 1

我最近更新到gradle 6.0.1（我想我做得正确，但是我对这一切还是很陌生的，并且Flutter Doctor没有问题。

这是我的项目级别build.gradle：

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

    dependencies {
        classpath 'com.android.tools.build:gradle:5.6.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:4.3.3'
    }
}

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
}

这是应用程序级别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.skypeclone1"
        minSdkVersion 16
        targetSdkVersion 28
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        multiDexEnabled true
    }

    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 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
apply plugin: 'com.google.gms.google-services'

这里是我的Gradle包装器属性，以防它们也很重要。

#Fri Jun 23 08:50:38 CEST 2017
distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.2-all.zip

Answer 1

您正在尝试使用实际的Gradle。对于Android开发，本月发布了当前版本为3.5.3的Android Gradle。阅读本文：https://developer.android.com/studio/releases/gradle-plugin#3-5-0。

编辑：要使用最新版本的Android Gradle（3.5.3），您需要的5.4.1-5.6.4之间的Gradle版本可以在gradle-wrapper.properties文件中进行配置。我猜Android Gradle尚不支持Gradle 6。