Gradle sync failed: Already disposed: Module: 'xxx' (6 s 502 ms)

问题：

编译时出现：Gradle sync failed: Already disposed: Module: 'xxxlibrary' (6 s 502 ms)

解决：在Android Studio 工具中：

1、 File > Invalidate Caches / Restart

2、弹框中选择 Invalidate and Restart

之后又出现另一个问题，如下：

“unsupported modules detected Compilation is not supported for following modules: app. Unfortunately you can’t have non-Gradle Java modules and Android-Gradle modules in one project”

然后底部状态栏下一直显示：“indexing paused due to batch update”；

解决方法：删除项目根目录删除.idea文件，重启Android Studio ;