系统：macOS 10.5
Android Studio 版本：3.4.2

将一个配置正确的项目文件夹直接拖到 Android Studio 窗口，即可打开

Android Studio.png

如果出错，说明配置有问题。首先检查机器有没有装 jdk 和 gradle

Jdk

打开 terminal

java -version

java -version.png

Gradle

gradle -v

gradle.png

Android Studio 是自带 gradle 的，只需要配置一下环境变量。

应用程序->Android Studio，右键显示包内容，找到gradle 路径

/Applications/Android\ Studio.app/Contents/gradle/gradle-5.1.1/bin/gradle

拖入 terminal 拷贝下来

terminal 输入命令

cd ~
touch .bash_profile
open -e .bash_profile

打开一个文件，添加

export GRADLE_HOME=/Applications/Android\ Studio.app/Contents/gradle/gradle-5.1.1
export PATH=${PATH}:${GRADLE_HOME}/bin

注意第一个路径到 gradle-版本号，第二个路径为 /bin

保存关闭，terminal 输入

source .bash_profile

如果权限不够，报错 Permission denied，输入

chmod +x /Applications/Android\ Studio.app/Contents/gradle/gradle-5.1.1/bin/gradle

然后查看有没有成功

gradle -v

项目配置

需要导入的项目名：YourProject
用 Android Studio 新建一个项目，名为 MyApplication，作为参考

项目/build.gradle

打开 YourProject/build.gradle，与 MyApplication/build.gradle 比较

YourProject/build.gradle:

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.3.3'
        //生成代码工具
        classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

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

MyApplication/build.gradle:

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.4.2'
        
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

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

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

明显看出 gradle 版本不同，且 YourProject/build.gradle 中缺少两个 google() ,多一个 classpath。

gradle 版本要改为和现有的相同，两句 google() 需要加上，多的这个 classpath 是 apt 的，需要删掉。

项目/gradle/wrapper/gradle-wrapper.properties

路径YourProject/gradle/wrapper/gradle-wrapper.properties，

打开 MyApplication/gradle/wrapper/gradle-wrapper.properties，发现除了 gradle 版本以外，其它都一样。直接复制内容过去，保存。

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip

项目/app/build.gradle

做完了上面的操作，把项目文件夹拖入 Android Studio，它就会报错

ERROR: Plugin with id 'com.neenbedankt.android-apt' not found.

ERROR: Plugin with id 'com.neenbedankt.android-apt' not found..png

下面有个 Open File，打开看到 项目/app/build.gradle 里有一句

apply plugin: 'com.neenbedankt.android-apt'

这一句要删掉，因为 Android Gradle 插件2.2版本发布后，Android 官方提供了 annotationProcessor 来代替 android-apt。

删掉后点按右上角小🔨，或按 command+ F9，重新编译

编译.png

报了很多错，点开第一个，报错信息是

Gradle DSL method not found: 'apt()'

Gradle DSL method not found: 'apt()'.png

将项目/app/build.gradle 里的 apt 直接改为 annotationProcessor

dependencies{
  ...
  // apt 'com.google.dagger:dagger-compiler:2.6'
  annotationProcessor  'com.google.dagger:dagger-compiler:2.6'
  ...
}

重新编译，报错

Annotation processors must be explicitly declared now.  The following dependencies on the compile classpath are found to contain annotation processor.  Please add them to the annotationProcessor configuration.
  - butterknife-5.1.1.jar (com.jakewharton:butterknife:5.1.1)

Annotation processors must be explicitly declared now. .png

android {
    ...
    defaultConfig {
        ...
        javaCompileOptions { annotationProcessorOptions { includeCompileClasspath = true } }
    }
    ...
}

重新编译，就会在 Run build 时卡着，

Run build.png

此时打开

/Users/[UserName]/.gradle

文件夹，创建一个文件，gradle.properties，内容为

org.gradle.daemon=true

回到 Android Studio，重新编译，报错

Lint found fatal errors while assembling a release target.

Lint found fatal errors while assembling a release target..png

按提示在 android 大括号下添加

lintOptions {       
        checkReleaseBuilds false                
        abortOnError false      
}

重新编译，编译成功。

重新打开 Android Studio，把项目文件夹拖入，报错

WARNING: Configuration 'compile' is obsolete and has been replaced with 'implementation' and 'api'.
It will be removed at the end of 2018. For more information see: http://d.android.com/r/tools/update-dependency-configurations.html
Affected Modules: app


WARNING: Configuration 'testCompile' is obsolete and has been replaced with 'testImplementation'.
It will be removed at the end of 2018. For more information see: http://d.android.com/r/tools/update-dependency-configurations.html
Affected Modules: app


WARNING: Configuration 'androidTestCompile' is obsolete and has been replaced with 'androidTestImplementation'.
It will be removed at the end of 2018. For more information see: http://d.android.com/r/tools/update-dependency-configurations.html
Affected Modules: app


WARNING: The specified Android SDK Build Tools version (26.0.1) is ignored, as it is below the minimum supported version (28.0.3) for Android Gradle Plugin 3.4.2.
Android SDK Build Tools 28.0.3 will be used.
To suppress this warning, remove "buildToolsVersion '26.0.1'" from your build.gradle file, as each version of the Android Gradle Plugin now has a default version of the build tools.
Remove Build Tools version and sync project
Affected Modules: app

前三个，按提示将 项目/app/build.gradle 文件里的关键字换掉。

1. 将 'compile' 换成 'implementation' 或者 'api'.
2. 将 'testCompile' 换成 'testImplementation'
3. 将 'androidTestCompile' 换成 'androidTestImplementation'

第四个，buildToolsVersion 不对，打开 MyApplication/app/build.gradle，看到 buildToolsVersion 为 29.0.1，直接修改掉。

顺便其它的 compileSdkVersion、minSdkVersion、targetSdkVersion，不一样的都改过来。

重新编译，通过
Run，通过
重新打开 Android Studio，把项目拖入，通过