OAApp/build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.4.2'
        classpath 'com.jakewharton:butterknife-gradle-plugin:9.0.0-rc2'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        // 添加下面的内容
        flatDir {
            dirs 'libs'
        }
        google()
        jcenter()
        maven { url "https://jitpack.io" }
        maven { url 'https://maven.google.com' }
    }
}

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