Flutter 卡在Running Gradle task 'assembleDebug'...

国内使用flutter需要在多处进行设置，本文是在flutter开发环境配置好，但是一直处于Running Gradle task 'assembleDebug'...，进行的讲解。（windows环境）
1.环境变量设置

PUB_HOSTED_URL=https://pub.flutter-io.cn
FLUTTER_STORAGE_BASE_URL=https://storage.flutter-io.cn

2.flutter项目的android目录中，gradle目录gradle-wrapper.properties，（hikvision安全开发环境，其他电脑环境不必设置）

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip

3.flutter项目的android目录中，项目的build.gradle

buildscript {
    repositories {
       
        maven { url 'https://maven.aliyun.com/repository/google' }
        maven { url 'https://maven.aliyun.com/repository/jcenter' }
        maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
    }
}

allprojects {
    repositories {
      
        maven { url 'https://maven.aliyun.com/repository/google' }
        maven { url 'https://maven.aliyun.com/repository/jcenter' }
        maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
    }
}

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

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

4.flutter的sdk中进行设置，处于此目录下D:\fluttersdk\packages\flutter_tools\gradle\flutter.gradle,

...
buildscript {
    repositories {

        maven { url 'https://maven.aliyun.com/repository/google' }
        maven { url 'https://maven.aliyun.com/repository/jcenter' }
        maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.4.0'
    }
}
...
class FlutterPlugin implements Plugin<Project> {
    private static final String DEFAULT_MAVEN_HOST = "https://storage.flutter-io.cn/download.flutter.io";
...

5.flutter的sdk中进行设置，处于此目录下D:\fluttersdk\packages\flutter_tools\gradle\resolve_dependencies.gradle,

...
repositories {

      maven { url 'https://maven.aliyun.com/repository/google' }
      maven { url 'https://maven.aliyun.com/repository/jcenter' }
      maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
      maven {
           url "https://storage.flutter-io.cn/download.flutter.io"
       }


}
...

6.清除缓存，重新运行