54 lines
1.3 KiB
C++
54 lines
1.3 KiB
C++
// Copyright Epic Games, Inc. All Rights Reserved.
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#pragma once
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#include "Internationalization/Text.h"
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class FDragDropOperation;
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class UWidget;
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class IWidgetDragDropExtension
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{
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public:
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virtual ~IWidgetDragDropExtension() { }
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virtual bool ShouldPreventDropOnTarget(const UWidget* Target, const TSharedPtr<FDragDropOperation>& DragDropOp) const = 0;
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virtual FText GetDropFailureText(const UWidget* Target, const TSharedPtr<FDragDropOperation>& DragDropOp) const = 0;
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};
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/**
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* Drag & drop extensibility manager holds a list of registered drag and drop extensions.
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*/
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class FWidgetDragDropExtensibilityManager
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{
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public:
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void AddExtension(const TSharedRef<IWidgetDragDropExtension>& Extension)
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{
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if (ensure(!Extensions.Contains(Extension)))
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{
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Extensions.Add(Extension);
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}
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}
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void RemoveExtension(const TSharedRef<IWidgetDragDropExtension>& Extension)
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{
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int32 NumRemoved = Extensions.RemoveSingleSwap(Extension);
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ensure(NumRemoved == 1);
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}
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TArrayView<const TSharedPtr<IWidgetDragDropExtension>> GetExtensions() const
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{
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return Extensions;
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}
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private:
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TArray<TSharedPtr<IWidgetDragDropExtension>> Extensions;
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};
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/** Indicates that a class can extend drag & drop functionality */
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class IHasWidgetDragDropExtensibility
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{
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public:
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virtual TSharedPtr<FWidgetDragDropExtensibilityManager> GetWidgetDragDropExtensibilityManager() = 0;
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};
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