Could not build module ' Uikit '

Create a new Singleview-app today unable to run the program, the first line of code in AppDelegate.h error.

#import <UIKit/UIKit.h>

/users/wjw/desktop/demo/demo_oc/singleview-app/singleview-app/main.m:9:9: Could not build module ' UIKit '

The result is treated as follows: Delete Modulecatche

All the internet is about deleting/users/youruser name/library/developer/xcode/deriveddata/modulecache

My computer is not used to showing hidden files (the library default seems to be hidden). The repository folder is not found under the Username folder

but in findingUsername folder when you press the ALT key, the Repository folder is displayed. Then you can find it in turn.Modulecache。 Then delete the cache contents in this folder.
Sometimes after you don't see this folder, and inDeriveddatafolder to see a lot of your own previously created project files directly deleted on the line. Does not affect the use.

Could not build module ' Uikit '