在Xcode 10.1中，我的解决方案是在文件菜单中的工作区设置中改变构建系统。它默认设置为New Build System，将其更改为Legacy Build System，这就成功了。

如果工作区中有多个项目，则需要:

向所有项目添加新配置 产品->清洁 删除派生数据 终端吊舱安装 构建您的项目。

确保Scheme中的“在构建中查找隐式依赖项”选项是打开的!

有几个潜在的错误配置可能会导致这个问题，

Please confirm that you have opened the .xcworkspace but not .xcodeproj file. Also make sure you have build Social first before you build TriviaApp. Make sure that iOS Deployment Target is set same for all modules with main app. For example is TriviaApps deployment target is set to 9.0, Socials deployment target also need to be set to 9.0. Make sure your main module (TriviaApp) and your used framework (Social) have same set of configurations. i.e. If your Project has three configurations, Debug, Release, ReleasePremium than your Social framework also need to have three configurations Debug, Release, ReleasePremium. Also make sure that the archive configuration is set same for both TriviaApp and Social. i.e. if your TriviaApps archive scheme is set to ReleasePremium, your Socials archive scheme also need to be set into ReleasePremium. Please assure that you do not need to import Social in each .swift files when its already added in the Bridging-Header.h. In case of issue came from Pod files, make sure you have uncommented #use_frameworks! into use_frameworks! from you Podfile. Sometime re installing pod works if Social has any dependency on pods. If none of the above steps works, delete your derived data folder and try re building.

在我的情况下，我尝试了上面的每一个建议仍然没有工作。 我只是复制文件的内容，显示错误没有导入的东西，并将其粘贴到另一个文件相同的导入和注释错误文件。 再次运行项目，它工作，然后我删除原来的错误文件，并创建一个同名的文件，并使其内容再次使用相同的导入。 我认为在我的情况下，我只是想办法让它能够链接那些导入一次，它应该是好的。

在我的例子中，我只需要重新加载项目。我使用命令行克隆我的项目，但它没有正确安装子模块。为了补救，我通过XCode克隆了项目，一切正常。只是要确保先备份所有更改。