C++與藍圖互調

本文轉載自查看原文 2018-06-27 15:57 1052 UnrealEngine4

Kismet庫

藍圖方法cpp使用
例：打LOG:Print String
藍圖節點的鼠標tips：Target is Kismet System Library

#include "Runtime/Engine/Classes/Kismet/KismetSystemLibrary.h"  
UKismetSystemLibrary::PrintString(this, s)  //KismetSystemLibrary 繼承UObject

C++打LOG

DEFINE_LOG_CATEGORY_STATIC(LogName, Log, All); //.cpp文件聲明LOG。注：LogName不能重，Log是個枚舉，All是個枚舉
UE_LOG(LogName, Log, TEXT("abc %s"),s);//可以像Printf樣打印出

DECLARE_LOG_CATEGORY_EXTERN(AAAAA, Log, All); //在.h文件聲明LOG
DEFINE_LOG_CATEGORY(AAAAA);//在.cpp文件使用

#include "Engine/Engine.h"
GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, FString::Printf(TEXT("%s %f"), *Msg, Value));//引擎打LOG  注意-1  這個key可以用來當消息池索引

藍圖 C++ 互調

BlueprintCallable

UFUNCTION(BlueprintCallable, Category = "test")
void SendMsg(FString msg);//供藍圖調用的C++函數

BlueprintImplementableEvent

UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "ReceiveEvent"))
void ReceiveEvent(const FString& message);//藍圖實現函數供C++調用

參考Actor BeginPlay：
meta=(DisplayName="BeginPlay")
void ReceiveBeginPlay
在C++ BeginPlay里調用ReceiveBeginPlay

BlueprintPure

UFUNCTION(BlueprintPure, Category = "TAMediator") //藍圖輸出綠色

BlueprintNativeEvent

UFUNCTION(BlueprintNativeEvent) //本函數可用C++或藍圖實現
void fun1();//藍圖覆寫函數
virtual void fun1_Implementation();//UHT生成 c++要重寫的函數

C++實現藍圖接口

UINTERFACE(Category = "My Interface", BlueprintType, meta = (DisplayName = "My Interface"))
class MYMODULE_API UMyInterface : public UInterface {
	GENERATED_UINTERFACE_BODY()
};

class MYMODULE_API IMyInterface {
    GENERATED_IINTERFACE_BODY()
public:
    UFUNCTION(BlueprintCallable)
    virtual void fun1();//Error
    
    UFUNCTION(BlueprintCallable)
    void fun1();//Error

    UFUNCTION(BlueprintNativeEvent)
    void fun1();//藍圖可覆寫

    /// My Initialization Interface.
    UFUNCTION(BlueprintNativeEvent, BlueprintCallable)
    void OnInitialized(const AMyActor* Context);//  藍圖可覆寫可調用

    UFUNCTION(BlueprintImplementableEvent)
    void Death();//True  在藍圖內以事件呈現
};

C++內調用 OnInitialized：

const auto &Interface = Cast<IMyInterface>(Actor);
if (Interface) {
    Interface->Execute_OnInitialized(Actor,Context);
}
// Else, Execute Interface on Blueprint layer instead:
if (Actor->GetClass()->ImplementsInterface(UMyInterface::StaticClass())) {
    IMyInterface::Execute_OnInitialized(Actor,Context);
}