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> Unreal Engine API Reference > Runtime > Engine > Engine > UObjectLibrary

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UObjectLibrary

Class that holds a library of Objects

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Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UObjectLibrary

References

Module	Engine
Header	/Engine/Source/Runtime/Engine/Classes/Engine/ObjectLibrary.h
Include	#include "Engine/ObjectLibrary.h"

Syntax

class UObjectLibrary : public UObject

Remarks

Class that holds a library of Objects

Variables

	Name	Description
TArray< FAssetD...	AssetDataList	Asset data of objects that will belong in library, possibly not loaded yet
bool	bHasBlueprintClasses	True if this library holds blueprint classes, false if it holds other objects
bool	bIncludeOnlyOnDiskAssets	Whether to set bIncludeOnlyOnDiskAssets when setting up AR filters for discovering asset data
bool	bIsFullyLoaded	True if we've already fully loaded this library, can't do it twice
bool	bIsGlobalAsyncScanEnvironment	True if we are running a build that is already scanning assets globally so we can perhaps avoid scanning paths synchronously
bool	bRecursivePaths	Whether to set bRecursivePaths when setting up AR filters for discovering asset data
bool	bUseWeakReferences	If this library should use weak pointers
TArray< FString...	DeferredAssetDataPaths	The paths that we will query again once assets are finished being discovered
TObjectPtr< UCl...	ObjectBaseClass	Class that Objects must be of.
TArray< TObject...	Objects	List of Objects in library
FObjectLibraryO...	OnObjectAddedEvent	Delegates for when an object is added or removed from this library.
FObjectLibraryO...	OnObjectRemovedEvent
TArray< TWeakOb...	WeakObjects	Weak pointers to objects

Constructors

	Name	Description
	UObjectLibrary ( const FObjectInitializer& ObjectIn... )

Functions

	Name	Description
bool	AddObject ( UObject* NewObject )	Attempt to add a new Object, return true if added
void	ClearLoaded()	Clears the current loaded objects and asset data
UObjectLibra...	CreateLibrary ( UClass* InBaseClass, bool bInHasBlueprintClasses, bool bInUseWeak )	Static function to create a new ObjectLibrary at runtime, with various options set There is now a better version of this functionality in AssetManager, if you are creating many game-specific libraries you should switch to using AssetManager instead
int32	GetAssetDataCount()	Returns the number of objects
void	GetAssetDataList ( TArray< FAssetData >& OutAssetData )	Returns the list of asset data
int32	GetObjectCount()	Returns the number of objects
void	GetObjects ( TArray< T* >& OutObjects )	Fills in a passed in array of objects, casts to proper type
bool	IsLibraryFullyLoaded()
int32	LoadAssetDataFromPath ( const FString& Path )
int32	LoadAssetDataFromPaths ( const TArray< FString >& Paths, bool bForceSynchronousScan )	Gets asset data for assets in a subdirectory. Returns number of assets data loaded
int32	LoadAssetsFromAssetData()	Load all of the objects in asset data list into memory
int32	LoadAssetsFromPath ( const FString& Path )
int32	LoadAssetsFromPaths ( const TArray< FString >& Paths )	Load an entire subdirectory of assets into this object library. Returns number of assets loaded
int32	LoadBlueprintAssetDataFromPath ( const FString& Path )
int32	LoadBlueprintAssetDataFromPaths ( const TArray< FString >& Paths, bool bForceSynchronousScan )	Load an entire subdirectory of blueprints into this object library.
int32	LoadBlueprintsFromPath ( const FString& Path )
int32	LoadBlueprintsFromPaths ( const TArray< FString >& Paths )	Load an entire subdirectory of blueprints into this object library.
void	OnAssetRegistryFilesLoaded()	Handler for when assets have finished scanning in the asset registry
FObjectLibra...	OnObjectAdded()
FObjectLibra...	OnObjectRemoved()
bool	RemoveObject ( UObject* ObjectToRemove )	Attempt to remove an Object from the object, return true if removed
void	UseWeakReferences ( bool bSetUseWeak )	Set rather this library is using weak or strong references

Overridden from UObject

		Name	Description
	void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Called when a property on this object has been modified externally
	void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.

Classes

	Name	Description
	FObjectLibraryOnObjectAdded
	FObjectLibraryOnObjectRemoved