vault backup: 2024-10-12 17:19:45

2024-10-12 17:19:46 +08:00
parent ff94ddca61
commit 244c0c52f6
960 changed files with 31348 additions and 10 deletions
--- a/03-UnrealEngine/Gameplay/UObject/UnrealSpecifiers/Meta/Component/AllowAnyActor.md
+++ b/03-UnrealEngine/Gameplay/UObject/UnrealSpecifiers/Meta/Component/AllowAnyActor.md
@@ -0,0 +1,97 @@
+# AllowAnyActor
+
+- **功能描述：** 用在ComponentReference属性上，在UseComponentPicker的情况下使得组件选取器扩大到场景里其他Actor下的其他组件。
+- **使用位置：** UPROPERTY
+- **引擎模块：** Component Property
+- **元数据类型：** bool
+- **限制类型：** FComponentReference，FSoftComponentReference
+- **关联项：** [UseComponentPicker](UseComponentPicker/UseComponentPicker.md)
+- **常用程度：** ★★
+
+用在ComponentReference属性上，在UseComponentPicker的情况下使得组件选取器扩大到场景里其他Actor下的其他组件。
+
+- 也要注意到，这个AllowAnyActor影响的只是UI上的组件选择。一个ComponentReference即使不加AllowAnyActor，也可以通过ReferencedActor引用到别的Actor，然后手填其属下的组件名字。然后可以正常的在C++里GetComponent里出来正确的组件对象。因此AllowAnyActor跟逻辑无关。
+
+测试代码和效果见UseComponentPicker。
+
+## 原理：
+
+主要是FComponentReferenceCustomization。根据源码查看，bAllowAnyActor 只在已经有bUseComponentPicker的情况下生效，且用来对Actor列表进行过滤。
+
+```cpp
+void FComponentReferenceCustomization::CustomizeHeader(TSharedRef<IPropertyHandle> InPropertyHandle, FDetailWidgetRow& HeaderRow, IPropertyTypeCustomizationUtils& CustomizationUtils)
+{
+	PropertyHandle = InPropertyHandle;
+
+	CachedComponent.Reset();
+	CachedFirstOuterActor.Reset();
+	CachedPropertyAccess = FPropertyAccess::Fail;
+
+	bAllowClear = false;
+	bAllowAnyActor = false;
+	bUseComponentPicker = PropertyHandle->HasMetaData(NAME_UseComponentPicker);
+	bIsSoftReference = false;
+
+	if (bUseComponentPicker)
+	{
+		FProperty* Property = InPropertyHandle->GetProperty();
+		check(CastField<FStructProperty>(Property) &&
+				(FComponentReference::StaticStruct() == CastFieldChecked<const FStructProperty>(Property)->Struct ||
+				FSoftComponentReference::StaticStruct() == CastFieldChecked<const FStructProperty>(Property)->Struct));
+
+		bAllowClear = !(InPropertyHandle->GetMetaDataProperty()->PropertyFlags & CPF_NoClear);
+		bAllowAnyActor = InPropertyHandle->HasMetaData(NAME_AllowAnyActor);
+		bIsSoftReference = FSoftComponentReference::StaticStruct() == CastFieldChecked<const FStructProperty>(Property)->Struct;
+
+		BuildClassFilters();
+		BuildComboBox();
+
+		InPropertyHandle->SetOnPropertyValueChanged(FSimpleDelegate::CreateSP(this, &FComponentReferenceCustomization::OnPropertyValueChanged));
+
+		// set cached values
+		{
+			CachedComponent.Reset();
+			CachedFirstOuterActor = GetFirstOuterActor();
+
+			FComponentReference TmpComponentReference;
+			CachedPropertyAccess = GetValue(TmpComponentReference);
+			if (CachedPropertyAccess == FPropertyAccess::Success)
+			{
+				CachedComponent = TmpComponentReference.GetComponent(CachedFirstOuterActor.Get());
+				if (!IsComponentReferenceValid(TmpComponentReference))
+				{
+					CachedComponent.Reset();
+				}
+			}
+		}
+
+		HeaderRow.NameContent()
+		[
+			InPropertyHandle->CreatePropertyNameWidget()
+		]
+		.ValueContent()
+		[
+			ComponentComboButton.ToSharedRef()
+		]
+		.IsEnabled(MakeAttributeSP(this, &FComponentReferenceCustomization::CanEdit));
+	}
+	else
+	{
+		HeaderRow.NameContent()
+		[
+			InPropertyHandle->CreatePropertyNameWidget()
+		]
+		.ValueContent()
+		[
+			InPropertyHandle->CreatePropertyValueWidget()
+		]
+		.IsEnabled(MakeAttributeSP(this, &FComponentReferenceCustomization::CanEdit));
+	}
+}
+
+bool FComponentReferenceCustomization::IsFilteredActor(const AActor* const Actor) const
+{
+	return bAllowAnyActor || Actor == CachedFirstOuterActor.Get();
+}
+
+```