Ue4/5 cannot open the file "xxx.generated.h" (cannot open file xxx.generated.h) solution summary

Unable to open xxx.generated.h yes UE One of the common problems in development , Sometimes people scratch their heads . This paper will summarize the author's various methods to solve this kind of problem in actual development , New methods will be added here in the future .

Method 1 , Delete Intermediate Folder , And regenerate

The first solution is to delete Intermediate Folder , Reuse uproject File generation VS Engineering documents （Generate Visual Studio project files）. It should be noted that ,Intermediate The folder is not only in the main project directory , There are also in the directories of various plug-ins .xxx.h Which directory does the file belong to , We will delete the directory Intermediate Folder .

We know , Various xxx.generated.h By UHT（Unreal Header Tool） Generated , And keep it in Intermediate Folder . Delete Intermediate Folder ,UHT Will regenerate generated.h file . So this method is effective .

Method 2 , Delete all generated files , Regenerate

UE In the engineering catalogue , Some files and folders are automatically generated by the system . In the following two figures , We highlighted these files , Also, don't forget that there are these files in the plug-in .

Delete .vs Folder 、Binaries Folder 、Intermediate Folder 、Saved Folder 、sln file , Not only can it solve xxx.generated.h The file cannot be opened , It can also solve other difficult and miscellaneous diseases . But here's the thing , In the delete Binaries Folder time , Be sure not to use it dll When the third-party library is deleted , Otherwise, the following problems will occur .

Method 3 ： Adjust module dependencies

If there are multiple modules in the plug-in , If the dependencies of these modules are not set correctly , It can also lead to xxx.generated.h Problems that cannot be opened . As shown in the figure below , Suppose the same plug-in , There are two modules AA and BB, And the module AA rely on BB. If in the module AA Of Build.cs There is no setting for BB Dependence （ As shown on the left in the figure below ）, Or put it right BB The dependence of is written in PrivateDependencyModuleNames in （ As shown in the right figure in the following figure ）, It will also lead to such problems .

Use the two settings above , Will lead to the following “ Can't open file ‘xxx.generated.h’” The problem of , The solution is in PublicDependencyModuleNames To the module BB Dependence . Here's an explanation PublicDependencyModuleNames and PrivateDependencyModuleNames The difference between ： Dependent on modules AA Other modules of , Such as the main file directory , Only its PublicDependencyModuleNames Modules exposed in , Cannot access PrivateDependencyModuleNames Modules declared in .