Android Studio 中的 Gradle 错误：找不到“com.android.tools.build:gradle:7.1.1”。

我正在尝试将项目从 Eclipse 导入到 Android Studio 中。 在 Eclipse 中，我将其导出到 gradle，然后将其导入到 Android Studio 中。 注意：我是 gradle 新手，对问题没有洞察力。 现在我得到这个错误：

> Configure project :
    Running gradle version: 6.8

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring root project 'aBooks'.
 > Could not resolve all artifacts for configuration ':classpath'.
 > Could not find com.android.tools.build:gradle:7.1.1.
 Searched in the following locations:
   - 
https://repo.maven.apache.org/maven2/com/android/tools/build/gradle/7.1.1/gradle-7.1.1.pom
 If the artifact you are trying to retrieve can be found in the repository but without metadata in 'Maven POM' format, you need to adjust the 'metadataSources { ... }' of the repository declaration.
 Required by:
     project : 

给出的链接会导致“404 页面未找到”。

我的系统上带有“gradle-7”的 gradle 文件是：

渐变文件：

buildscript {
// added crl  https://tomgregory.com/anatomy-of-a-gradle-build-script/
repositories {
    mavenCentral()
}
println "Running gradle version: $gradle.gradleVersion"
dependencies {
    classpath 'com.android.tools.build:gradle:7.1.1'  // **original error here**
    // https://mvnrepository.com/artifact/com.android.tools.build/gradle
   // implementation group: 'com.android.tools.build', name: 'gradle', version: '7.1.0-alpha01'
    //  https://mvnrepository.com/artifact/com.android.tools.build/gradle/7.1.0-alpha01
}
}

apply plugin: 'com.android.application'   // 'android'


dependencies {
implementation fileTree(dir: 'libs', include: '*.jar')
implementation project(':CRLibs')
implementation 'com.android.support:support-annotations:28.0.0'
implementation 'androidx.legacy:legacy-support-v4:1.0.0'

}

android {
compileSdk 26
buildToolsVersion "32.0.0"

buildFeatures {
    prefab true
    prefabPublishing true
}


sourceSets {
    main {
        manifest.srcFile 'AndroidManifest.xml'
        java.srcDirs = ['src']
        resources.srcDirs = ['src']
        aidl.srcDirs = ['src']
        renderscript.srcDirs = ['src']
        res.srcDirs = ['res']
        assets.srcDirs = ['assets']
    }

    // Move the tests to tests/java, tests/res, etc...
    instrumentTest.setRoot('tests')

    // Move the build types to build-types/<type>
    // For instance, build-types/debug/java, build-types/debug/AndroidManifest.xml, 
...
    // This moves them out of them default location under src/<type>/... which would
    // conflict with src/ being used by the main source set.
    // Adding new build types or product flavors should be accompanied
    // by a similar customization.
    debug.setRoot('build-types/debug')
    release.setRoot('build-types/release')
}
compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_8
}
dependenciesInfo {
    includeInApk true
    includeInBundle true
}

// no joy
plugins { // added crl https://developer.android.com/studio/releases/gradle-plugin#groovy
    id 'com.android.application' version '7.0.0-alpha13' apply false
    id 'com.android.library' version '7.0.0-alpha13' apply false
    id 'org.jetbrains.kotlin.android' version '1.5.31' apply false
}

}

我尝试将“7.1.1”更改为“7.2”，但没有任何变化。我不知道如何解决这个问题。我搜索中给出的所有答案与此处的版本不匹配或者没有帮助。

编辑1： 添加了信息。当我转到文件->项目结构和项目时，我看到

请注意，Gradle 版本是空白的。如果我输入 6.8 或 7.1.1 并单击“确定”，我会得到相同的结果，然后如果我返回，Gradle 版本将为空白。 Gradle 版本 6.8 在当前版本中被识别（参见错误消息的第 2 行。不知道这是否意味着什么。 这是我的 Gradel-6* 文件的列表：

Add google()给你的repositories { }堵塞。 Android Gradle 插件位于此处。