UE5 UMG中添加SearchableComboBox

原创

fengyuzaitu 2023-08-03 10:01:32 博主文章分类：图像处理 ©著作权

©著作权归作者所有：来自51CTO博客作者fengyuzaitu的原创作品，请联系作者获取转载授权，否则将追究法律责任

需求

实现可以搜索提示的Combox

代码

SMySearchableComboBox.h

// Copyright Epic Games, Inc. All Rights Reservekd.

#pragma once

#include "CoreMinimal.h"
#include "Input/Reply.h"
#include "Widgets/SWidget.h"
#include "Widgets/Input/SComboButton.h"
#include "Widgets/Input/SEditableTextBox.h"
#include "Widgets/Views/SListView.h"
#include "Widgets/Input/SComboBox.h"

/**
 * A searchable text combo box
 */
class TESTMOUSEINPUT_API SMySearchableComboBox : public SComboButton
{
public:
	/** Type of list used for showing menu options. */
	typedef SListView< TSharedPtr<FString> > SComboListType;
	/** Delegate type used to generate widgets that represent Options */
	typedef typename TSlateDelegates< TSharedPtr<FString> >::FOnGenerateWidget FOnGenerateWidget;
	typedef typename TSlateDelegates< TSharedPtr<FString> >::FOnSelectionChanged FOnSelectionChanged;

	SLATE_BEGIN_ARGS(SMySearchableComboBox)
		: _Content()
		, _ComboBoxStyle(&FAppStyle::Get().GetWidgetStyle<FComboBoxStyle>("ComboBox"))
		, _ButtonStyle(nullptr)
		, _ItemStyle(&FAppStyle::Get().GetWidgetStyle<FTableRowStyle>("ComboBox.Row"))
		, _ContentPadding(_ComboBoxStyle->ContentPadding)
		, _ForegroundColor(FSlateColor::UseStyle())
		, _OptionsSource()
		, _OnSelectionChanged()
		, _OnGenerateWidget()
		, _InitiallySelectedItem(nullptr)
		, _Method()
		, _MaxListHeight(450.0f)
		, _HasDownArrow(true)
		, _SearchVisibility()
	{}

	/** Slot for this button's content (optional) */
	SLATE_DEFAULT_SLOT(FArguments, Content)

		SLATE_STYLE_ARGUMENT(FComboBoxStyle, ComboBoxStyle)

		/** The visual style of the button part of the combo box (overrides ComboBoxStyle) */
		SLATE_STYLE_ARGUMENT(FButtonStyle, ButtonStyle)

		SLATE_STYLE_ARGUMENT(FTableRowStyle, ItemStyle)

		SLATE_ATTRIBUTE(FMargin, ContentPadding)
		SLATE_ATTRIBUTE(FSlateColor, ForegroundColor)

		SLATE_ARGUMENT(const TArray< TSharedPtr<FString> >*, OptionsSource)
		SLATE_EVENT(FOnSelectionChanged, OnSelectionChanged)
		SLATE_EVENT(FOnGenerateWidget, OnGenerateWidget)

		/** Called when combo box is opened, before list is actually created */
		SLATE_EVENT(FOnComboBoxOpening, OnComboBoxOpening)

		/** The custom scrollbar to use in the ListView */
		SLATE_ARGUMENT(TSharedPtr<SScrollBar>, CustomScrollbar)

		/** The option that should be selected when the combo box is first created */
		SLATE_ARGUMENT(TSharedPtr<FString>, InitiallySelectedItem)

		SLATE_ARGUMENT(TOptional<EPopupMethod>, Method)

		/** The max height of the combo box menu */
		SLATE_ARGUMENT(float, MaxListHeight)

		/**
		 * When false, the down arrow is not generated and it is up to the API consumer
		 * to make their own visual hint that this is a drop down.
		 */
		SLATE_ARGUMENT(bool, HasDownArrow)

		/** Allow setting the visibility of the search box dynamically */
		SLATE_ATTRIBUTE(EVisibility, SearchVisibility)

	SLATE_END_ARGS()

	/**
	 * Construct the widget from a declaration
	 *
	 * @param InArgs   Declaration from which to construct the combo box
	 */
	void Construct(const FArguments& InArgs);

	void ClearSelection();

	void SetSelectedItem(TSharedPtr<FString> InSelectedItem);

	/** @return the item currently selected by the combo box. */
	TSharedPtr<FString> GetSelectedItem();

	/**
	 * Requests a list refresh after updating options
	 * Call SetSelectedItem to update the selected item if required
	 * @see SetSelectedItem
	 */
	void RefreshOptions();

protected:
	/** Set ths source data for this combo box */
	void SetOptionsSource(const TArray< TSharedPtr<FString> >* InOptionsSource);

private:

	/** Generate a row for the InItem in the combo box's list (passed in as OwnerTable). Do this by calling the user-specified OnGenerateWidget */
	TSharedRef<ITableRow> GenerateMenuItemRow(TSharedPtr<FString> InItem, const TSharedRef<STableViewBase>& OwnerTable);

	/** Called if the menu is closed */
	void OnMenuOpenChanged(bool bOpen);

	/** Invoked when the selection in the list changes */
	void OnSelectionChanged_Internal(TSharedPtr<FString> ProposedSelection, ESelectInfo::Type SelectInfo);

	/** Invoked when the search text changes */
	void OnSearchTextChanged(const FText& ChangedText);

	/** Sets the current selection to the first valid match when user presses enter in the filter box */
	void OnSearchTextCommitted(const FText& InText, ETextCommit::Type InCommitType);

	/** Handle clicking on the content menu */
	virtual FReply OnButtonClicked() override;

	/** The item style to use. */
	const FTableRowStyle* ItemStyle;

	/** The padding around each menu row */
	FMargin MenuRowPadding;
private:
	/** Delegate that is invoked when the selected item in the combo box changes */
	FOnSelectionChanged OnSelectionChanged;
	/** The item currently selected in the combo box */
	TSharedPtr<FString> SelectedItem;
	/** The search field used for the combox box's contents */
	TSharedPtr<SEditableTextBox> SearchField;
	/** The ListView that we pop up; visualized the available options. */
	TSharedPtr< SComboListType > ComboListView;
	/** The Scrollbar used in the ListView. */
	TSharedPtr< SScrollBar > CustomScrollbar;
	/** Delegate to invoke before the combo box is opening. */
	FOnComboBoxOpening OnComboBoxOpening;
	/** Delegate to invoke when we need to visualize an option as a widget. */
	FOnGenerateWidget OnGenerateWidget;

	/** Updated whenever search text is changed */
	FText SearchText;

	/** Source data for this combo box */
	const TArray< TSharedPtr<FString> >* OptionsSource;

	/** Filtered list that is actually displayed */
	TArray< TSharedPtr<FString> > FilteredOptionsSource;
};

SMySearchableComboBox.cpp

// Copyright Epic Games, Inc. All Rights Reservekd.

#include "SMySearchableComboBox.h"
#include "Framework/Application/SlateUser.h"

#define LOCTEXT_NAMESPACE "SearchableComboBox"

void SMySearchableComboBox::Construct(const FArguments& InArgs)
{
	check(InArgs._ComboBoxStyle);

	ItemStyle = InArgs._ItemStyle;
	MenuRowPadding = InArgs._ComboBoxStyle->MenuRowPadding;

	// Work out which values we should use based on whether we were given an override, or should use the style's version
	const FComboButtonStyle& OurComboButtonStyle = InArgs._ComboBoxStyle->ComboButtonStyle;
	const FButtonStyle* const OurButtonStyle = InArgs._ButtonStyle ? InArgs._ButtonStyle : &OurComboButtonStyle.ButtonStyle;

	this->OnComboBoxOpening = InArgs._OnComboBoxOpening;
	this->OnSelectionChanged = InArgs._OnSelectionChanged;
	this->OnGenerateWidget = InArgs._OnGenerateWidget;

	OptionsSource = InArgs._OptionsSource;
	CustomScrollbar = InArgs._CustomScrollbar;

	FilteredOptionsSource.Append(*OptionsSource);

	TAttribute<EVisibility> SearchVisibility = InArgs._SearchVisibility;
	const EVisibility CurrentSearchVisibility = SearchVisibility.Get();

	TSharedRef<SWidget> ComboBoxMenuContent =
		SNew(SBox)
		.MaxDesiredHeight(InArgs._MaxListHeight)
		[
			SNew(SVerticalBox)

			+ SVerticalBox::Slot()
			.AutoHeight()
			[
				SAssignNew(this->SearchField, SEditableTextBox)
				.HintText(LOCTEXT("Search", "Search"))
				.OnTextChanged(this, &SMySearchableComboBox::OnSearchTextChanged)
				.OnTextCommitted(this, &SMySearchableComboBox::OnSearchTextCommitted)
				.Visibility(SearchVisibility)
			]

			+ SVerticalBox::Slot()
			[
				SAssignNew(this->ComboListView, SComboListType)
				.ListItemsSource(&FilteredOptionsSource)
				.OnGenerateRow(this, &SMySearchableComboBox::GenerateMenuItemRow)
				.OnSelectionChanged(this, &SMySearchableComboBox::OnSelectionChanged_Internal)
				.SelectionMode(ESelectionMode::Single)
				.ExternalScrollbar(InArgs._CustomScrollbar)
			]
		];

	// Set up content
	TSharedPtr<SWidget> ButtonContent = InArgs._Content.Widget;
	if (InArgs._Content.Widget == SNullWidget::NullWidget)
	{
		SAssignNew(ButtonContent, STextBlock)
			.Text(NSLOCTEXT("SMySearchableComboBox", "ContentWarning", "No Content Provided"))
			.ColorAndOpacity(FLinearColor::Red);
	}


	SComboButton::Construct(SComboButton::FArguments()
		.ComboButtonStyle(&OurComboButtonStyle)
		.ButtonStyle(OurButtonStyle)
		.Method(InArgs._Method)
		.ButtonContent()
		[
			ButtonContent.ToSharedRef()
		]
		.MenuContent()
		[
			ComboBoxMenuContent
		]
		.HasDownArrow(InArgs._HasDownArrow)
		.ContentPadding(InArgs._ContentPadding)
		.ForegroundColor(InArgs._ForegroundColor)
		.OnMenuOpenChanged(this, &SMySearchableComboBox::OnMenuOpenChanged)
		.IsFocusable(true)
		);

	if (CurrentSearchVisibility == EVisibility::Visible)
	{
		SetMenuContentWidgetToFocus(SearchField);
	}
	else
	{
		SetMenuContentWidgetToFocus(ComboListView);
	}

	// Need to establish the selected item at point of construction so its available for querying
	// NB: If you need a selection to fire use SetItemSelection rather than setting an IntiallySelectedItem
	SelectedItem = InArgs._InitiallySelectedItem;
	if (TListTypeTraits<TSharedPtr<FString>>::IsPtrValid(SelectedItem))
	{
		ComboListView->Private_SetItemSelection(SelectedItem, true);
	}

}

void SMySearchableComboBox::ClearSelection()
{
	ComboListView->ClearSelection();
}

void SMySearchableComboBox::SetSelectedItem(TSharedPtr<FString> InSelectedItem)
{
	if (TListTypeTraits<TSharedPtr<FString>>::IsPtrValid(InSelectedItem))
	{
		ComboListView->SetSelection(InSelectedItem, ESelectInfo::OnNavigation);
	}
	else
	{
		ComboListView->SetSelection(SelectedItem, ESelectInfo::OnNavigation);
	}
}

TSharedPtr<FString> SMySearchableComboBox::GetSelectedItem()
{
	return SelectedItem;
}

void SMySearchableComboBox::RefreshOptions()
{
	// Need to refresh filtered list whenever options change
	FilteredOptionsSource.Reset();

	if (SearchText.IsEmpty())
	{
		FilteredOptionsSource.Append(*OptionsSource);
	}
	else
	{
		for (TSharedPtr<FString> Option : *OptionsSource)
		{
			if (Option->Find(SearchText.ToString(), ESearchCase::Type::IgnoreCase) >= 0)
			{
				FilteredOptionsSource.Add(Option);
			}
		}
	}

	ComboListView->RequestListRefresh();
}

void SMySearchableComboBox::SetOptionsSource(const TArray<TSharedPtr<FString>>* InOptionsSource)
{
	OptionsSource = InOptionsSource;

	FilteredOptionsSource.Empty();
	FilteredOptionsSource.Append(*OptionsSource);
}

TSharedRef<ITableRow> SMySearchableComboBox::GenerateMenuItemRow(TSharedPtr<FString> InItem, const TSharedRef<STableViewBase>& OwnerTable)
{
	if (OnGenerateWidget.IsBound())
	{
		return SNew(SComboRow<TSharedPtr<FString>>, OwnerTable)
			.Style(ItemStyle)
			.Padding(MenuRowPadding)
			[
				OnGenerateWidget.Execute(InItem)
			];
	}
	else
	{
		return SNew(SComboRow<TSharedPtr<FString>>, OwnerTable)
			[
				SNew(STextBlock).Text(NSLOCTEXT("SlateCore", "ComboBoxMissingOnGenerateWidgetMethod", "Please provide a .OnGenerateWidget() handler."))
			];

	}
}

void SMySearchableComboBox::OnMenuOpenChanged(bool bOpen)
{
	if (bOpen == false)
	{
		if (TListTypeTraits<TSharedPtr<FString>>::IsPtrValid(SelectedItem))
		{
			// Ensure the ListView selection is set back to the last committed selection
			ComboListView->SetSelection(SelectedItem, ESelectInfo::OnNavigation);
		}

		// Set focus back to ComboBox for users focusing the ListView that just closed
		TSharedRef<SWidget> ThisRef = AsShared();
		FSlateApplication::Get().ForEachUser([&ThisRef](FSlateUser& User) {
			if (User.HasFocusedDescendants(ThisRef))
			{
				User.SetFocus(ThisRef);
			}
		});

	}
}


void SMySearchableComboBox::OnSelectionChanged_Internal(TSharedPtr<FString> ProposedSelection, ESelectInfo::Type SelectInfo)
{
	if (!ProposedSelection)
	{
		return;
	}

	// Ensure that the proposed selection is different from selected
	if (ProposedSelection != SelectedItem)
	{
		SelectedItem = ProposedSelection;
		OnSelectionChanged.ExecuteIfBound(ProposedSelection, SelectInfo);
	}

	// close combo as long as the selection wasn't from navigation
	if (SelectInfo != ESelectInfo::OnNavigation)
	{
		this->SetIsOpen(false);
	}
	else
	{
		ComboListView->RequestScrollIntoView(SelectedItem, 0);
	}
}

void SMySearchableComboBox::OnSearchTextChanged(const FText& ChangedText)
{
	SearchText = ChangedText;

	RefreshOptions();
}

void SMySearchableComboBox::OnSearchTextCommitted(const FText& InText, ETextCommit::Type InCommitType)
{
	if ((InCommitType == ETextCommit::Type::OnEnter) && FilteredOptionsSource.Num() > 0)
	{
		ComboListView->SetSelection(FilteredOptionsSource[0], ESelectInfo::OnKeyPress);
	}
}

FReply SMySearchableComboBox::OnButtonClicked()
{
	// if user clicked to close the combo menu
	if (this->IsOpen())
	{
		// Re-select first selected item, just in case it was selected by navigation previously
		TArray<TSharedPtr<FString>> SelectedItems = ComboListView->GetSelectedItems();
		if (SelectedItems.Num() > 0)
		{
			OnSelectionChanged_Internal(SelectedItems[0], ESelectInfo::Direct);
		}
	}
	else
	{
		SearchField->SetText(FText::GetEmpty());
		OnComboBoxOpening.ExecuteIfBound();
	}

	return SComboButton::OnButtonClicked();
}

#undef LOCTEXT_NAMESPACE

MyComboBoxStringSearchable.h

// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreMinimal.h"
#include "UObject/ObjectMacros.h"
#include "Fonts/SlateFontInfo.h"
#include "Layout/Margin.h"
#include "Styling/SlateColor.h"
#include "Styling/SlateTypes.h"
#include "Widgets/SWidget.h"
#include "SMySearchableComboBox.h"
#include "Widgets/Input/SComboBox.h"
#include "Components/Widget.h"

#include "MyComboBoxStringSearchable.generated.h"

/**
 * The combobox allows you to display a list of options to the user in a dropdown menu for them to select one.
 */
UCLASS(meta=( DisplayName="MyComboBoxStringSearch (String)"))
class TESTMOUSEINPUT_API UMyComboBoxStringSearchable : public UWidget
{
	GENERATED_UCLASS_BODY()

	DECLARE_DYNAMIC_MULTICAST_DELEGATE_TwoParams(FOnSelectionChangedEvent, FString, SelectedItem, ESelectInfo::Type, SelectionType);
	DECLARE_DYNAMIC_MULTICAST_DELEGATE(FOnOpeningEvent);

private:

	/** The default list of items to be displayed on the combobox. */
	UPROPERTY(EditAnywhere, Category=Content)
	TArray<FString> DefaultOptions;

	/** The item in the combobox to select by default */
	UPROPERTY(EditAnywhere, Category=Content)
	FString SelectedOption;

public:

	/** The style. */
	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category=Style, meta=( DisplayName="Style" ))
	FComboBoxStyle WidgetStyle;

	/** The item row style. */
	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category=Style)
	FTableRowStyle ItemStyle;

	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Content)
	FMargin ContentPadding;

	/** The max height of the combobox list that opens */
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Content, AdvancedDisplay)
	float MaxListHeight;

	/**
	 * When false, the down arrow is not generated and it is up to the API consumer
	 * to make their own visual hint that this is a drop down.
	 */
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Content, AdvancedDisplay)
	bool HasDownArrow;

	/**
	* When false, directional keys will change the selection. When true, ComboBox 
	* must be activated and will only capture arrow input while activated.
	*/
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Content, AdvancedDisplay)
	bool EnableGamepadNavigationMode;

	/**
	 * The default font to use in the combobox, only applies if you're not implementing OnGenerateWidgetEvent
	 * to factory each new entry.
	 */
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Style)
	FSlateFontInfo Font;

	/** The foreground color to pass through the hierarchy. */
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Style, meta=(DesignerRebuild))
	FSlateColor ForegroundColor;

	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category=Interaction)
	bool bIsFocusable;

public: // Events

	/** Called when the widget is needed for the item. */
	UPROPERTY(EditAnywhere, Category=Events, meta=( IsBindableEvent="True" ))
	FGenerateWidgetForString OnGenerateWidgetEvent;

	/** Called when a new item is selected in the combobox. */
	UPROPERTY(BlueprintAssignable, Category=Events)
	FOnSelectionChangedEvent OnSelectionChanged;

	/** Called when the combobox is opening */
	UPROPERTY(BlueprintAssignable, Category=Events)
	FOnOpeningEvent OnOpening;

public:

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	void AddOption(const FString& Option);

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	bool RemoveOption(const FString& Option);

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	int32 FindOptionIndex(const FString& Option) const;

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	FString GetOptionAtIndex(int32 Index) const;

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	void ClearOptions();

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	void ClearSelection();

	/**
	 * Refreshes the list of options.  If you added new ones, and want to update the list even if it's
	 * currently being displayed use this.
	 */
	UFUNCTION(BlueprintCallable, Category="ComboBox")
	void RefreshOptions();

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	void SetSelectedOption(FString Option);

	UFUNCTION(BlueprintCallable, Category = "ComboBox")
	void SetSelectedIndex(const int32 Index);

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	FString GetSelectedOption() const;

	UFUNCTION(BlueprintCallable, Category="ComboBox")
	int32 GetSelectedIndex() const;

	/** Returns the number of options */
	UFUNCTION(BlueprintCallable, Category="ComboBox")
	int32 GetOptionCount() const;
	
	UFUNCTION(BlueprintCallable, Category="ComboBox", Meta = (ReturnDisplayName = "bOpen"))
	bool IsOpen() const;

	//~ Begin UVisual Interface
	virtual void ReleaseSlateResources(bool bReleaseChildren) override;
	//~ End UVisual Interface

	//~ Begin UObject Interface
	virtual void PostInitProperties() override;
	virtual void Serialize(FArchive& Ar) override;
	virtual void PostLoad() override;
	//~ End UObject Interface

#if WITH_EDITOR
	virtual const FText GetPaletteCategory() override;
#endif

protected:
	/** Refresh ComboBoxContent with the correct widget/data when the selected option changes */
	void UpdateOrGenerateWidget(TSharedPtr<FString> Item);

	/** Called by slate when it needs to generate a new item for the combobox */
	virtual TSharedRef<SWidget> HandleGenerateWidget(TSharedPtr<FString> Item) const;

	/** Called by slate when the underlying combobox selection changes */
	virtual void HandleSelectionChanged(TSharedPtr<FString> Item, ESelectInfo::Type SelectionType);

	/** Called by slate when the underlying combobox is opening */
	virtual void HandleOpening();

	//~ Begin UWidget Interface
	virtual TSharedRef<SWidget> RebuildWidget() override;
	//~ End UWidget Interface

protected:
	/** The true objects bound to the Slate combobox. */
	TArray< TSharedPtr<FString> > Options; 

	/** A shared pointer to the underlying slate combobox */
	TSharedPtr< SMySearchableComboBox > MyComboBox;

	/** A shared pointer to a container that holds the combobox content that is selected */
	TSharedPtr< SBox > ComboBoxContent;

	/** If OnGenerateWidgetEvent is not bound, this will store the default STextBlock generated */
	TWeakPtr<STextBlock> DefaultComboBoxContent;

	/** A shared pointer to the current selected string */
	TSharedPtr<FString> CurrentOptionPtr;
};

MyComboBoxStringSearchable.cpp

// Copyright Epic Games, Inc. All Rights Reserved.

#include "MyComboBoxStringSearchable.h"
#include "Widgets/SNullWidget.h"
#include "UObject/EditorObjectVersion.h"
#include "UObject/ConstructorHelpers.h"
#include "Engine/Font.h"
#include "Styling/UMGCoreStyle.h"

#define LOCTEXT_NAMESPACE "MyComboBoxStringSearchable"

/////////////////////////////////////////////////////
// UComboBoxString

static FComboBoxStyle* DefaultComboBoxStyle = nullptr;
static FTableRowStyle* DefaultComboBoxRowStyle = nullptr;

#if WITH_EDITOR
static FComboBoxStyle* EditorComboBoxStyle = nullptr;
static FTableRowStyle* EditorComboBoxRowStyle = nullptr;
#endif 

UMyComboBoxStringSearchable::UMyComboBoxStringSearchable(const FObjectInitializer& ObjectInitializer)
	: Super(ObjectInitializer)
{
	if (DefaultComboBoxStyle == nullptr)
	{
		DefaultComboBoxStyle = new FComboBoxStyle(FUMGCoreStyle::Get().GetWidgetStyle<FComboBoxStyle>("ComboBox"));

		// Unlink UMG default colors.
		DefaultComboBoxStyle->UnlinkColors();
	}

	if (DefaultComboBoxRowStyle == nullptr)
	{
		DefaultComboBoxRowStyle = new FTableRowStyle(FUMGCoreStyle::Get().GetWidgetStyle<FTableRowStyle>("TableView.Row"));

		// Unlink UMG default colors.
		DefaultComboBoxRowStyle->UnlinkColors();
	}

	WidgetStyle = *DefaultComboBoxStyle;
	ItemStyle = *DefaultComboBoxRowStyle;

#if WITH_EDITOR 
	if (EditorComboBoxStyle == nullptr)
	{
		EditorComboBoxStyle = new FComboBoxStyle(FCoreStyle::Get().GetWidgetStyle<FComboBoxStyle>("EditorUtilityComboBox"));

		// Unlink UMG Editor colors from the editor settings colors.
		EditorComboBoxStyle->UnlinkColors();
	}

	if (EditorComboBoxRowStyle == nullptr)
	{
		EditorComboBoxRowStyle = new FTableRowStyle(FCoreStyle::Get().GetWidgetStyle<FTableRowStyle>("TableView.Row"));

		// Unlink UMG Editor colors from the editor settings colors.
		EditorComboBoxRowStyle->UnlinkColors();
	}

	if (IsEditorWidget())
	{
		WidgetStyle = *EditorComboBoxStyle;
		ItemStyle = *EditorComboBoxRowStyle;

		// The CDO isn't an editor widget and thus won't use the editor style, call post edit change to mark difference from CDO
		PostEditChange();
	}
#endif // WITH_EDITOR

	WidgetStyle.UnlinkColors();
	ItemStyle.UnlinkColors();

	ForegroundColor = ItemStyle.TextColor;
	bIsFocusable = true;

	ContentPadding = FMargin(4.0, 2.0);
	MaxListHeight = 450.0f;
	HasDownArrow = true;
	EnableGamepadNavigationMode = true;
	// We don't want to try and load fonts on the server.
	if ( !IsRunningDedicatedServer() )
	{
		static ConstructorHelpers::FObjectFinder<UFont> RobotoFontObj(*UWidget::GetDefaultFontName());
		Font = FSlateFontInfo(RobotoFontObj.Object, 16, FName("Bold"));
	}
}

void UMyComboBoxStringSearchable::PostInitProperties()
{
	Super::PostInitProperties();

	// Initialize the set of options from the default set only once.
	for (const FString& DefaultOption : DefaultOptions)
	{
		AddOption(DefaultOption);
	}
}

void UMyComboBoxStringSearchable::ReleaseSlateResources(bool bReleaseChildren)
{
	Super::ReleaseSlateResources(bReleaseChildren);

	MyComboBox.Reset();
	ComboBoxContent.Reset();
}

void UMyComboBoxStringSearchable::Serialize(FArchive& Ar)
{
	Super::Serialize(Ar);

	Ar.UsingCustomVersion(FEditorObjectVersion::GUID);
}

void UMyComboBoxStringSearchable::PostLoad()
{
	Super::PostLoad();

	// Initialize the set of options from the default set only once.
	for (const FString& DefaultOption : DefaultOptions)
	{
		AddOption(DefaultOption);
	}

	if (GetLinkerCustomVersion(FEditorObjectVersion::GUID) < FEditorObjectVersion::ComboBoxControllerSupportUpdate)
	{
		EnableGamepadNavigationMode = false;
	}
}

TSharedRef<SWidget> UMyComboBoxStringSearchable::RebuildWidget()
{
	int32 InitialIndex = FindOptionIndex(SelectedOption);
	if ( InitialIndex != -1 )
	{
		CurrentOptionPtr = Options[InitialIndex];
	}

	MyComboBox =
		SNew(SMySearchableComboBox)
		.ComboBoxStyle(&WidgetStyle)
		.ItemStyle(&ItemStyle)
		.ForegroundColor(ForegroundColor)
		.OptionsSource(&Options)
		.InitiallySelectedItem(CurrentOptionPtr)
		.ContentPadding(ContentPadding)
		.MaxListHeight(MaxListHeight)
		.HasDownArrow(HasDownArrow)
		//.EnableGamepadNavigationMode(EnableGamepadNavigationMode)
		.OnGenerateWidget(BIND_UOBJECT_DELEGATE(SMySearchableComboBox::FOnGenerateWidget, HandleGenerateWidget))
		.OnSelectionChanged(BIND_UOBJECT_DELEGATE(SMySearchableComboBox::FOnSelectionChanged, HandleSelectionChanged))
		.OnComboBoxOpening(BIND_UOBJECT_DELEGATE(FOnComboBoxOpening, HandleOpening))
		//.IsFocusable(bIsFocusable)
		[
			SAssignNew(ComboBoxContent, SBox)
		];

	if ( InitialIndex != -1 )
	{
		// Generate the widget for the initially selected widget if needed
		UpdateOrGenerateWidget(CurrentOptionPtr);
	}

	return MyComboBox.ToSharedRef();
}

void UMyComboBoxStringSearchable::AddOption(const FString& Option)
{
	Options.Add(MakeShareable(new FString(Option)));

	RefreshOptions();
}

bool UMyComboBoxStringSearchable::RemoveOption(const FString& Option)
{
	int32 OptionIndex = FindOptionIndex(Option);

	if ( OptionIndex != -1 )
	{
		if ( Options[OptionIndex] == CurrentOptionPtr )
		{
			ClearSelection();
		}

		Options.RemoveAt(OptionIndex);

		RefreshOptions();

		return true;
	}

	return false;
}

int32 UMyComboBoxStringSearchable::FindOptionIndex(const FString& Option) const
{
	for ( int32 OptionIndex = 0; OptionIndex < Options.Num(); OptionIndex++ )
	{
		const TSharedPtr<FString>& OptionAtIndex = Options[OptionIndex];

		if ( ( *OptionAtIndex ) == Option )
		{
			return OptionIndex;
		}
	}

	return -1;
}

FString UMyComboBoxStringSearchable::GetOptionAtIndex(int32 Index) const
{
	if (Index >= 0 && Index < Options.Num())
	{
		return *(Options[Index]);
	}
	return FString();
}

void UMyComboBoxStringSearchable::ClearOptions()
{
	ClearSelection();

	Options.Empty();

	if ( MyComboBox.IsValid() )
	{
		MyComboBox->RefreshOptions();
	}
}

void UMyComboBoxStringSearchable::ClearSelection()
{
	CurrentOptionPtr.Reset();

	if ( MyComboBox.IsValid() )
	{
		MyComboBox->ClearSelection();
	}

	if ( ComboBoxContent.IsValid() )
	{
		ComboBoxContent->SetContent(SNullWidget::NullWidget);
	}
}

void UMyComboBoxStringSearchable::RefreshOptions()
{
	if ( MyComboBox.IsValid() )
	{
		MyComboBox->RefreshOptions();
	}
}

void UMyComboBoxStringSearchable::SetSelectedOption(FString Option)
{
	int32 InitialIndex = FindOptionIndex(Option);
	SetSelectedIndex(InitialIndex);
}

void UMyComboBoxStringSearchable::SetSelectedIndex(const int32 Index)
{
	if (Options.IsValidIndex(Index))
	{
		CurrentOptionPtr = Options[Index];
		// Don't select item if its already selected
		if (SelectedOption != *CurrentOptionPtr)
		{
			SelectedOption = *CurrentOptionPtr;

			if (ComboBoxContent.IsValid())
			{
				MyComboBox->SetSelectedItem(CurrentOptionPtr);
				UpdateOrGenerateWidget(CurrentOptionPtr);
			}		
			else
			{
				HandleSelectionChanged(CurrentOptionPtr, ESelectInfo::Direct);
			}
		}
	}
}
FString UMyComboBoxStringSearchable::GetSelectedOption() const
{
	if (CurrentOptionPtr.IsValid())
	{
		return *CurrentOptionPtr;
	}
	return FString();
}

int32 UMyComboBoxStringSearchable::GetSelectedIndex() const
{
	if (CurrentOptionPtr.IsValid())
	{
		for (int32 OptionIndex = 0; OptionIndex < Options.Num(); ++OptionIndex)
		{
			if (Options[OptionIndex] == CurrentOptionPtr)
			{
				return OptionIndex;
			}
		}
	}

	return -1;
}

int32 UMyComboBoxStringSearchable::GetOptionCount() const
{
	return Options.Num();
}

bool UMyComboBoxStringSearchable::IsOpen() const
{
	return MyComboBox.IsValid() && MyComboBox->IsOpen();
}

void UMyComboBoxStringSearchable::UpdateOrGenerateWidget(TSharedPtr<FString> Item)
{
	// If no custom widget was supplied and the default STextBlock already exists,
	// just update its text instead of rebuilding the widget.
	if (DefaultComboBoxContent.IsValid() && (IsDesignTime() || OnGenerateWidgetEvent.IsBound()))
	{
		const FString StringItem = Item.IsValid() ? *Item : FString();
		DefaultComboBoxContent.Pin()->SetText(FText::FromString(StringItem));
	}
	else
	{
		DefaultComboBoxContent.Reset();
		ComboBoxContent->SetContent(HandleGenerateWidget(Item));
	}
}

TSharedRef<SWidget> UMyComboBoxStringSearchable::HandleGenerateWidget(TSharedPtr<FString> Item) const
{
	FString StringItem = Item.IsValid() ? *Item : FString();

	// Call the user's delegate to see if they want to generate a custom widget bound to the data source.
	if ( !IsDesignTime() && OnGenerateWidgetEvent.IsBound() )
	{
		UWidget* Widget = OnGenerateWidgetEvent.Execute(StringItem);
		if ( Widget != NULL )
		{
			return Widget->TakeWidget();
		}
	}

	// If a row wasn't generated just create the default one, a simple text block of the item's name.
	return SNew(STextBlock)
		.Text(FText::FromString(StringItem))
		.Font(Font);
}

void UMyComboBoxStringSearchable::HandleSelectionChanged(TSharedPtr<FString> Item, ESelectInfo::Type SelectionType)
{
	CurrentOptionPtr = Item;
	SelectedOption = CurrentOptionPtr.IsValid() ? CurrentOptionPtr.ToSharedRef().Get() : FString();

	// When the selection changes we always generate another widget to represent the content area of the combobox.
	if ( ComboBoxContent.IsValid() )
	{
		UpdateOrGenerateWidget(CurrentOptionPtr);
	}

	if ( !IsDesignTime() )
	{
		OnSelectionChanged.Broadcast(Item.IsValid() ? *Item : FString(), SelectionType);
	}
}

void UMyComboBoxStringSearchable::HandleOpening()
{
	OnOpening.Broadcast();
}

#if WITH_EDITOR

const FText UMyComboBoxStringSearchable::GetPaletteCategory()
{
	return LOCTEXT("Input", "Input");
}

#endif

/////////////////////////////////////////////////////

#undef LOCTEXT_NAMESPACE

修改testmouseinput.Build.cs文件

PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "UMG", "Slate", "SlateCore" });

最终效果

UE5 UMG中添加SearchableComboBox_UE5 UMG SearchCombox

总结

实际上该控件是在列表上添加一个搜索的编辑框，还需要改进，直接替换掉显示框

上一篇：UE5 USplineComponent

下一篇：UE5 蓝图运行时错误："“无访问”正在尝试读取属性

提问和评论都可以，用心的回复会被更多人看到评论

发布评论

相关文章

官方博客	全部文章	热门标签	班级博客
了解我们	网站地图	意见反馈

鸿蒙开发者社区	51CTO学堂
51CTO	软考资讯