UObject实例化

创建一个MyObject类

在Default Pawn Class 中实现

注意：要实现运行时调用可在这里提前配置，具体参考之前文章

#include "MyObject.h"UCLASS()
class DEMO_API AMyPawn : public APawn
{GENERATED_BODY()public:// Sets default values for this pawn's propertiesAMyPawn();protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;public:// Called every framevirtual void Tick(float DeltaTime) override;UPROPERTY(EditAnywhere)UMyObject *MyCustomObject;
};

// Called when the game starts or when spawned
void AMyPawn::BeginPlay()
{Super::BeginPlay();// 使用模板类TSubclassOf创建对象TSubclassOf<UMyObject> MyObjectClass = UMyObject::StaticClass();MyCustomObject = NewObject<UMyObject>(GetWorld(), MyObjectClass);if (MyCustomObject){UE_LOG(LogTemp, Warning, TEXT("MyCustomObject is %s"),*MyCustomObject->GetName());}
}

点击运行，打印日志

MyObject中参数调用

//构造函数
FDateTableStruct();

ublic:// 隐式创建并调用无参构造器// 隐式创建方式在进程虚拟地址空间中的栈中分配内存，它的分配和释放由系统决定，// 函数内局部变量的存储单元可以在栈上创建，函数执行完毕，系统会自动释放这些存储单元。UPROPERTY()FDateTableStruct MyDateTableStruct;// 显式创建并调用无参构造器// 这种创建方式和第一种一样，在进程虚拟地址空间中的栈中分配内存，// 它的分配和释放由系统决定，函数内局部变量的存储单元可以在栈上创建，函数执行完毕，系统会自动释放这些存储单元。// FDateTableStruct MyDateTableStruct = FDateTableStruct();

在MyObject.h中实现

#pragma once#include "CoreMinimal.h"
#include "Engine/DataTable.h"
#include "UObject/NoExportTypes.h"
#include "MyObject.generated.h"USTRUCT(BlueprintType)
struct FDateTableStruct : public FTableRowBase
{GENERATED_USTRUCT_BODY()//构造函数FDateTableStruct();UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "DateTableStruct")FString ID;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "DateTableStruct")FString Name;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "DateTableStruct")int32 Age;
};/****/
UCLASS()
class DEMO_API UMyObject : public UObject
{GENERATED_BODY()public:// 隐式创建并调用无参构造器// 隐式创建方式在进程虚拟地址空间中的栈中分配内存，它的分配和释放由系统决定，// 函数内局部变量的存储单元可以在栈上创建，函数执行完毕，系统会自动释放这些存储单元。UPROPERTY()FDateTableStruct MyDateTableStruct;// 显式创建并调用无参构造器// 这种创建方式和第一种一样，在进程虚拟地址空间中的栈中分配内存，// 它的分配和释放由系统决定，函数内局部变量的存储单元可以在栈上创建，函数执行完毕，系统会自动释放这些存储单元。// FDateTableStruct MyDateTableStruct = FDateTableStruct();
};

在MyObject.cpp中实现

#include "MyObject.h"FDateTableStruct::FDateTableStruct()
{ID = "1001";Name = "Kurenai";Age = 18;
}

调用参数：

// Called when the game starts or when spawned
void AMyPawn::BeginPlay()
{Super::BeginPlay();// 使用模板类TSubclassOf创建对象TSubclassOf<UMyObject> MyObjectClass = UMyObject::StaticClass();MyCustomObject = NewObject<UMyObject>(GetWorld(), MyObjectClass);if (MyCustomObject){UE_LOG(LogTemp, Warning, TEXT("MyCustomObject is %s"), *MyCustomObject->GetName());UE_LOG(LogTemp, Warning, TEXT("MyCustomObject  ID is %s"), *MyCustomObject->MyDateTableStruct.ID);UE_LOG(LogTemp, Warning, TEXT("MyCustomObject  Name is %s"), *MyCustomObject->MyDateTableStruct.Name);UE_LOG(LogTemp, Warning, TEXT("MyCustomObject  Age is %d"), MyCustomObject->MyDateTableStruct.Age);}
}

打印日志：

UGameInstance实例化

GameInstance是全局唯一单例，这个在引擎初始化的时候就已经生成，一直存在到引擎关闭。
主要用于为游戏保存全局临时数据，想要持久化保存需要用SaveGame。

创建GameInstance

UMyGameInstance.h

#pragma once#include "CoreMinimal.h"
#include "Engine/GameInstance.h"
#include "MyGameInstance.generated.h"/****/
UCLASS()
class DEMO_API UMyGameInstance : public UGameInstance
{GENERATED_BODY()public:
//构造函数UMyGameInstance();//添加数据成员UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGameInstance")FString AppID;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGameInstance")FString AppKey;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGameInstance")FString AppName;UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "MyGameInstance")FString AppVersion;
};

UMyGameInstance.cpp

#include "MyGameInstance.h"UMyGameInstance::UMyGameInstance()
{AppID = "123456789";AppKey = "qwertyuiop";AppName = "MyGame";AppVersion = "1.0.0";
}

在MyPawn中调用

#include "MyGameInstance.h"UCLASS()
class DEMO_API AMyPawn : public APawn
{GENERATED_BODY()public:// Sets default values for this pawn's propertiesAMyPawn();protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;public:UPROPERTY()UMyGameInstance *MyGameInstance;
};

// Called when the game starts or when spawned
void AMyPawn::BeginPlay()
{Super::BeginPlay();MyGameInstance = Cast<UMyGameInstance>(GetWorld()->GetFirstPlayerController()->GetGameInstance());if (MyGameInstance){UE_LOG(LogTemp, Warning, TEXT("MyGameInstance AppName is %s"), *MyGameInstance->AppName);UE_LOG(LogTemp, Warning, TEXT("MyGameInstance AppID is %s"), *MyGameInstance->AppID);UE_LOG(LogTemp, Warning, TEXT("MyGameInstance AppKey is %s"), *MyGameInstance->AppKey);UE_LOG(LogTemp, Warning, TEXT("MyGameInstance AppVersion is %s"), *MyGameInstance->AppVersion);}
}

编译后，在项目设置中配置

输出日志：