Android Studio 3.6.1设置gradle的离线模

方式一

View > Tool Windows > Gradle from the menu bar. Then, near the top of the Gradle window, click Toggle Offline Mode

方式二

直接打开Gradle视图，点击对应按钮即可，如下图所示：

参考

https://stackoverflow.com/questions/60481987/no-cached-version-gradle-plugin-available-for-offline-mode