删除无用的asset

已经在地图中使用的asset会有asset reference

EditorAssetLibrary（按F12）open header file，会有如下一个功能，可以找asset reference，返回bool值

	UFUNCTION(BlueprintCallable, Category = "Editor Scripting | Asset")
	static TArray<FString> FindPackageReferencersForAsset(const FString& AssetPath, bool bLoadAssetsToConfirm = false);

for (const FAssetData& SelectedAssetData : SelectedAssetsData) 是一个范围循环（range-based for loop），通常在 Unreal Engine 中用于遍历一个容器中的所有元素。

: 在 for 循环中的用法是用于范围循环（range-based for loop）的语法符号。“在”或者“属于”

ObjectTools.h中的非强制删除。可以让使用者有一个确认删除的机会。

UNREALED_API int32 DeleteAssets( const TArray<FAssetData>& AssetsToDelete, bool bShowConfirmation = true );

如下报错（unresolved external symbal) means we need to add module to Build.cs file

UnrealEd means Unreal Editor

		PublicDependencyModuleNames.AddRange(
			new string[]
			{
				"Core","Blutility","EditorScriptingUtilities","UMG","Niagara","UnrealEd"
				// ... add other public dependencies that you statically link with here ...
			}
			);

示例代码

	UFUNCTION(CallInEditor)
	void RemoveUnusedAssets();

// Fill out your copyright notice in the Description page of Project Settings.


#include "AssetAction/QuickAssetAction.h"
#include "DebugHeader.h"
#include "EditorUtilityLibrary.h"
#include "EditorAssetLibrary.h"
#include "ObjectTools.h" //新增


void UQuickAssetAction::RemoveUnusedAssets()
{
	TArray<FAssetData> SelectedAssetsData = UEditorUtilityLibrary::GetSelectedAssetData();
	TArray<FAssetData> UnusedAssetsData;

	for (const FAssetData& SelectedAssetData : SelectedAssetsData) 
	{
		TArray<FString> AssetReferencers =
			UEditorAssetLibrary::FindPackageReferencersForAsset(SelectedAssetData.ObjectPath.ToString());

		if (AssetReferencers.Num() == 0) {
			UnusedAssetsData.Add(SelectedAssetData);
		}//把它加入废物列表
	}

	if (UnusedAssetsData.Num() == 0) {
		ShowMsgDialog(EAppMsgType::Ok, TEXT("No unused asset found among selected assets"), false);
		return;
	}

	else {
		const int32 NumOfAssetsDeleted = ObjectTools::DeleteAssets(UnusedAssetsData);//执行删除
		ShowNotifyInfo(TEXT("Successfully deleted " + FString::FromInt(NumOfAssetsDeleted) + TEXT(" unused assets.")));
	}

	//const int32 NumOfAssetDeleted = ObjectTools::DeleteAssets(UnusedAssetsData);//执行删除
	//if (NumOfAssetDeleted == 0)return;
	//ShowNotifyInfo(TEXT("Successfully deleted " + FString::FromInt(NumOfAssetsDeleted) + TEXT(" unused assets.")));
}

可读性：可以考虑将未使用资产的查找和删除逻辑分成两个独立的函数

插件效果