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03-UnrealEngine/Gameplay/UObject/UnrealSpecifiers/Meta/DetailsPanel/InlineEditConditionToggle/InlineEditConditionToggle.md

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+# InlineEditConditionToggle
+
+- **功能描述：** 使这个bool属性在被用作EditCondition的时候内联到对方的属性行里成为一个单选框，而不是自己成为一个编辑行。
+- **使用位置：** UPROPERTY
+- **元数据类型：** bool
+- **限制类型：** bool
+- **关联项：** [EditCondition](../EditCondition/EditCondition.md)
+- **常用程度：** ★★★★★
+
+使这个bool属性在被用作EditCondition的时候内联到对方的属性行里成为一个单选框，而不是自己成为一个编辑行。
+
+虽然EditCondition支持别的类型属性或者是表达式，但是这个InlineEditConditionToggle只支持bool属性。
+
+## 测试代码：
+
+```cpp
+public:
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = InlineEditConditionToggle, meta = (InlineEditConditionToggle))
+	bool MyBool_Inline;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = InlineEditConditionToggle, meta = (EditCondition = "MyBool_Inline"))
+	int32 MyInt_EditCondition_UseInline = 123;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = InlineEditConditionToggle)
+	int32 MyThirdInt_Inline = 123;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = InlineEditConditionToggle, meta = (EditCondition = "MyThirdInt_Inline>200"))
+	int32 MyInt_EditConditionExpression_UseInline = 123;
+```
+
+## 测试效果：
+
+可见MyBool_Inline变成了单选框。而MyThirdInt_Inline就没有被隐藏掉。
+
+![InlineEditConditionToggle](InlineEditConditionToggle.gif)
+
+## 原理：
+
+可以看到用这个判断是否支持出现单选框。
+
+```cpp
+
+bool FPropertyNode::SupportsEditConditionToggle() const
+{
+	if (!Property.IsValid())
+	{
+		return false;
+	}
+
+	FProperty* MyProperty = Property.Get();
+
+	static const FName Name_HideEditConditionToggle("HideEditConditionToggle");
+	if (EditConditionExpression.IsValid() && !Property->HasMetaData(Name_HideEditConditionToggle))
+	{
+		const FBoolProperty* ConditionalProperty = EditConditionContext->GetSingleBoolProperty(EditConditionExpression);
+		if (ConditionalProperty != nullptr)
+		{
+			// There are 2 valid states for inline edit conditions:
+			// 1. The property is marked as editable and has InlineEditConditionToggle set. 
+			// 2. The property is not marked as editable and does not have InlineEditConditionToggle set.
+			// In both cases, the original property will be hidden and only show up as a toggle.
+
+			static const FName Name_InlineEditConditionToggle("InlineEditConditionToggle");
+			const bool bIsInlineEditCondition = ConditionalProperty->HasMetaData(Name_InlineEditConditionToggle);
+			const bool bIsEditable = ConditionalProperty->HasAllPropertyFlags(CPF_Edit);
+
+			if (bIsInlineEditCondition == bIsEditable)
+			{
+				return true;
+			}
+
+			if (bIsInlineEditCondition && !bIsEditable)
+			{
+				UE_LOG(LogPropertyNode, Warning, TEXT("Property being used as inline edit condition is not editable, but has redundant InlineEditConditionToggle flag. Field \"%s\" in class \"%s\"."), *ConditionalProperty->GetNameCPP(), *Property->GetOwnerStruct()->GetName());
+				return true;
+			}
+
+			// The property is already shown, and not marked as inline edit condition.
+			if (!bIsInlineEditCondition && bIsEditable)
+			{
+				return false;
+			}
+		}
+	}
+
+	return false;
+}
+```