vault backup: 2025-08-29 17:08:18

03-UnrealEngine/Gameplay/Lyra/UE5 Lyra学习笔记(8)—EnhanceInput（UE5.5）.md

@@ -150,11 +150,11 @@ void ULyraHeroComponent::InitializePlayerInput(UInputComponent* PlayerInputCompo
 			{
 				for (const FInputMappingContextAndPriority& Mapping : DefaultInputMappings)
 				{
-					//获取UInputMappingContext并进行注册。
 					if (UInputMappingContext* IMC = Mapping.InputMapping.Get())
 					{
 						if (Mapping.bRegisterWithSettings)
 						{ 
+							//将IMC注册给UEnhancedInputUserSettings
 							if (UEnhancedInputUserSettings* Settings = Subsystem->GetUserSettings())
 							{
 								Settings->RegisterInputMappingContext(IMC);
@@ -162,7 +162,8 @@ void ULyraHeroComponent::InitializePlayerInput(UInputComponent* PlayerInputCompo
 							
 							FModifyContextOptions Options = {};
 							Options.bIgnoreAllPressedKeysUntilRelease = false;
-							// Actually add the config to the local player							
+							// Actually add the config to the local player	
+							//实际添加IMC给LocalPlayer						
 							Subsystem->AddMappingContext(IMC, Mapping.Priority, Options);
 						}
 					}
@@ -211,7 +212,68 @@ void ULyraHeroComponent::InitializePlayerInput(UInputComponent* PlayerInputCompo
 
 ## 步骤
 1. 假设已经配置好了IMC以及IA。
-	1. 在Controller中注册IMC与IA？
+	1. 在Controller/Character中注册IMC与IA？
+	2. AddMappingContext()的选项OptionsNotifyUserSettings设置为true，会调用UEnhancedInputUserSettings::RegisterInputMappingContext()
 2. ProjectSettings - Engine - EnhancedInput - UserSettings中的Enable User Settings
 3. 配置IA中的UserSetting选项。 
-	1. 
+	1. 1
+
+## 加载按键设置逻辑
+默认自动加载，载入逻辑位于UEnhancedInputUserSettings::LoadOrCreateSettings()，调用顺序是：
+UEnhancedInputLocalPlayerSubsystem::Initialize
+->
+UEnhancedInputLocalPlayerSubsystem::InitalizeUserSettings() 
+->
+UEnhancedInputUserSettings::LoadOrCreateSettings()
+
+```c++
+UEnhancedInputUserSettings* UEnhancedInputUserSettings::LoadOrCreateSettings(ULocalPlayer* LocalPlayer)
+{
+	UEnhancedInputUserSettings* Settings = nullptr;
+
+	if (!LocalPlayer)
+	{
+		UE_LOG(LogEnhancedInput, Log, TEXT("Unable to determine an owning Local Player for the given Enhanced Player Input object"));
+		return nullptr;
+	}
+	
+	// If the save game exists, load it.
+	if (UGameplayStatics::DoesSaveGameExist(UE::EnhancedInput::SETTINGS_SLOT_NAME, LocalPlayer->GetLocalPlayerIndex()))
+	{
+		USaveGame* Slot = UGameplayStatics::LoadGameFromSlot(UE::EnhancedInput::SETTINGS_SLOT_NAME, LocalPlayer->GetLocalPlayerIndex());
+		Settings = Cast<UEnhancedInputUserSettings>(Slot);
+	}
+
+	// If there is no settings save game object, then we can create on
+	// based on the class type set in the developer settings
+	const UEnhancedInputDeveloperSettings* DevSettings = GetDefault<UEnhancedInputDeveloperSettings>();
+	UClass* SettingsClass = DevSettings->UserSettingsClass ? DevSettings->UserSettingsClass.Get() : UEnhancedInputUserSettings::StaticClass();
+
+	// This property is marked as "NoClear", so this should be impossible.
+	if (!ensureMsgf(SettingsClass, TEXT("Invalid Enhanced Input User settings class!")))
+	{
+		return nullptr;
+	}
+	
+	UE_CLOG((Settings && (Settings->GetClass() != SettingsClass)),
+		LogEnhancedInput,
+		Log,
+		TEXT("[%hs] Enhanced Input User Settings class has been changed from '%s' to '%s'. A new settings save object will be created (your saved settings will be reset)"),
+		__func__, *GetNameSafe(Settings->GetClass()), *GetNameSafe(SettingsClass));
+	
+	// If the settings are null (they dont exist yet) or the class has changed, we need to create a new object.
+	// The class can change if you modify it in the editor to be something else
+	if (Settings == nullptr || (Settings->GetClass() != SettingsClass))
+	{
+		Settings = Cast<UEnhancedInputUserSettings>(UGameplayStatics::CreateSaveGameObject(SettingsClass));
+	}
+
+	if (ensure(Settings))
+	{
+		Settings->Initialize(LocalPlayer);
+    	Settings->ApplySettings();	
+	}
+
+	return Settings;
+}
+```