Alwliu

UE4_C++笔记

目录

C++

获取当前世界指针

UWorld* World = GWorld;

或者

UWorld* World = GEgine->GetWorldContexts()[0].World();

创建文件夹拾取窗口

  • Module：DesktopPlatform
  • Header：IDesktopPlatform.h
IDesktopPlatform* DesktopPlatform = FDesktopPlatformModule::Get();
if(DesktopPlatform)
{
    TSharedPtr<SWindow> ParentWindow = FSlateApplication::Get().FindWidgetWindow(AsShared());
    void* ParentWindowHandle = (ParentWindow.IsValid() && ParentWindow->GetNativeWindow().IsValid()) ? ParentWindow->GetNativeWindow()->GetOSWindowHandle() : nullptr;
    
    FString FolderName;
    const FString Title = "Choose a repository location";
    const bool bFolderSelected = DesktopPlatform->OpenDirectoryDialog(ParentWindowHandle, Title, "", FolderName);
    if(bFolderSelected)
    {
        this->ExportSettingWidgetsPtr->DirectoryText->SetText(FText::FromString(FolderName));
    }
}

获取Actor所在地图名称

FString Dir,LevelName;
Actor->GetLevel->GetPackage()->GetFName().ToString().Split("/",&Dir,&LevelName,ESearchCase::IgnoreCase,ESearchDir::FromEnd);

选择世界里所有指定类型的Actor

  • Module: Engine
  • Header: EngineUtils.h
UWorld* World = GWorld;
TArray<AActor*> NeedSelectActors;
for (TActorIterator<AActor> It(World,AStaticMeshActor::StaticClass());It;++It)
{
    NeedSelectActors.Add(*It);
}

获取当前世界所有已加载关卡

UWorld* = GWorld;
TArray<ULevel*> Levels;
Levels = World->GetLevels();

获取当前选择的已加载关卡

  • Module: Engine
  • Header: LevelUtils.h
UWorld* = GWorld;
TArray<ULevel*> SelectedLevels;
for (ULevel* level : World->GetSelectedLevels())
{
    // 判断该地图是否加载了
    if (FLevelUtils::IsLevelLoaded(level))
    {
        SelectedLevels.Add(level);
    }
}

获取关卡名称

ULevel* CurrentLevel;
FString L, LevelName;
CurrentLevel->GetPackage()->GetFName().ToString().Split("/", &L, &LevelName, ESearchCase::IgnoreCase, ESearchDir::FromEnd);

判断文件/路径是否存在

  • Module: Core
  • Header: Misc/Paths.h
FString filePath, directory;
FPaths::FileExists(filePath);
FPaths::DirectoryExists(directory);

通过文件路径获取资产

  • Module: Core
  • Header: Modules/ModuleManager.h
FString AssetPath;
FAssetData Asset = FModuleManager::LoadModuleChecked<FAssetRegistryModule>("AssetRegistry").Get().GetAssetByObjectPath(*AssetPath);

添加撤回操作

const FScopedTransaction Transaction(FText::FromString("Operator name"))
obj->Modify();// 记录该obj编辑前状态

obj->progress();// 修改操作

添加任务进度条

GWarn->BeginSlowTask(FText::FromString("Message"), true);

/*
Progress...
*/
GWarn->UpdateProgress(i, total);

GWarn->EndSlowTask();

数据用JSON格式导出

  • Module: Json
  • Header:
    • Dom/JsonObject.h
    • Misc/FileHelper.h
    • Serialization/JsonSerializer.h
FString JsonStr;
TSharedPtr<FJsonObject> Obj = MakeShareable(new FJsonObject());
TSharedRef<TJsonWriter<TCHAR>> jsonWriter = TJsonWriterFactory<TCHAR>::Create(&JsonStr);

// key,value成对写入到FString
FString key, value;
Obj->SetStringField(key, value);

// 写到文件
FString filePath;
FJsonSerializer::Serialize(Obj.ToSharedRef(), jsonWriter);
FFileHelper::SaveStringToFile(JsonStr, filePath);

/*
Out file:
{
    key1: value1,
    key2: value2,
    ...
}
*/

从外部JSON文件读取数据

  • Module: Json
  • Header:
    • Dom/JsonObject.h
    • Misc/FileHelper.h
    • Serialization/JsonSerializer.h
FString filePath, jsonStr;
FFileHelper::LoadFileToString(jsonStr, *filePath);

TSharedPtr<FJsonObject> Obj = MakeShareable(new FJsonObject());
TSharedRef<TJsonReader<>> JsonReader = TJsonReaderFactory<>::Create(jsonStr);

if (FJsonSerializer::Deserialize(JsonReader,Obj))
{
    const FString value = Obj->GetStringField("key1");// return value1
}

Slate

编辑器式样

  • Module: EditorStyle
  • Header: EditorStyleSet.h

  • File path: Source\Editor\EditorStyle\Private\SlateEditorStyle.cpp
SNew(SButton)
.ButtonStyle(FEditorStyle::Get(), "HoverHintOnly")// 按钮式样
[
    SNew(SImage)
    .Image(FEditorStyle::GetBrush("PropertyWindow.Button_Delete"))// 图标
]

posted @ 2022-04-01 15:11  Alwliu  阅读(417)  评论(0)  编辑  收藏  举报