右键单击在项目视图中的目录上，确保未启用隐藏忽略的文件选项。

Right click on a directory in the project view and make sure Hide ignored files option is not enabled.

此功能由第三方提供。ignore 插件。 IntelliJ IDEA不会隐藏被忽略的文件。

This feature is provided by a third-party .ignore plug-in. IntelliJ IDEA doesn't hide ignored files out of the box.