ext { var = '27.0.3' }// Top-level build file where you can add configuration options common to all sub-projects/modules. buildscript { repositories { jcenter() google() } dependencies { classpath 'com.android.tools.build:gradle:3.3.1' classpath 'com.jakewharton:butterknife-gradle-plugin:10.0.0' //添加这一行 // NOTE: Do not place your application dependencies here; they belong // in the individual module build.gradle files } } allprojects { repositories { maven { url 'http://maven.aliyun.com/nexus/content/groups/public/' } maven { url 'https://jitpack.io' } jcenter() google() } } task clean(type: Delete) { delete rootProject.buildDir }