您似乎没有 .NET Core SDK 1.0.0-rc4 已安装.

It looks like you do not have the .NET Core SDK 1.0.0-rc4 installed.

如果没有安装 SDK，Visual Studio for Mac Preview 3 将找不到任何要导入的 SDK MSBuild 文件，这导致不会将调试/发布配置添加到项目中.

Without the SDK installed Visual Studio for Mac Preview 3 will not find any SDK MSBuild files to import which results in no Debug/Release configurations being added to the project.

Visual Studio for Mac 在/usr/local/share/dotnet/sdk/目录中查找最新的 sdk.如果该目录中没有子目录，则说明您没有安装 SDK.

Visual Studio for Mac looks in the /usr/local/share/dotnet/sdk/ directory for the latest sdk. If there are no subdirectories in that directory then you do not have the SDK installed.

项目中也没有文件显示，如果没有找到SDK也会出现这种情况.

Also there are no files shown in the project which will also occur if there is no SDK found.

目前，Visual Studio for Mac 没有关于缺少 SDK 的良好错误报告，但计划在未来版本中提供.

Currently Visual Studio for Mac does not have good error reporting about the missing SDK but this is planned for a future release.