The Android Gradle plugin supports only Kotlin Gradle plugin version 1.2.51 and higher.

Android编译出错：The Android Gradle plugin supports only Kotlin Gradle plugin version 1.2.51 and higher. Project ‘Test’ is using version 1.2.30.

解决方法：

1.打开build.gradle（Project）

2.修改buildscript中的ext.kotlin_version = ‘1.2.30’ 改成ext.kotlin_version = ‘1.2.51’

buildscript {
    ext.kotlin_version = '1.2.51'
}

3.rebuild