在用Android StudioBuild项目时，提示：Could not resolve all files for configuration ':classpath'.Could not find com.android.tools.

Error:Gradle: A problem occurred configuring root project ‘MyApplication‘.
> Could not resolve all files for configuration ‘:classpath‘.
   > Could not find com.android.tools.build:gradle:3.0.0.
     Searched in the following locations:
         https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.0/gradle-3.0.0.pom
         https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.0/gradle-3.0.0.jar
     Required by:
         project :

buildscript {
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath ‘com.android.tools.build:gradle:3.0.0‘
    }
}

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

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