我的Unity Editor版本是2020.3.37f1c1

1. 去Editor的安装目录，找modules.json

2. 之后搜“JDK”，找JDK的下载地址

http://download.unitychina.cn/download_unity/open-jdk/open-jdk-win-x64/jdk8u172-b11_4be8440cc514099cfe1b50cbc74128f6955cd90fd5afe15ea7be60f832de67b4.zip

3. 将下载的JDK放到默认目录

Unity>Edit>Preferences>External Tools

D:\Program Files\Unity 2020.3.37f1c1\Editor\Data\PlaybackEngines\AndroidPlayer\OpenJDK

如果没有对应文件夹就自己创建

1. sdk-tools-windows-4333796.zip 对应放到 SDK/tools 目录下

SDK国内能下载的地址(浏览器输入此地址)：

https://dl.google.com/android/repository/sdk-tools-windows-4333796.zip

D:\Program Files\Unity 2020.3.37f1c1\Editor\Data\PlaybackEngines\AndroidPlayer\SDK\tools

2. platform-tools_r28.0.1-windows.zip 对应放到 SDK/platform-tools 目录下

https://dl.google.com/android/repository/platform-tools_r28.0.1-windows.zip

3. platform-29_r05.zip 对应放到 SDK/platform目录下

https://dl.google.com/android/repository/platform-29_r05.zip

NDK国内能下载的地址：

https://dl.google.com/android/repository/android-ndk-r19-windows-x86_64.zip