FDragDropOperation Class Reference

#include <DragAndDrop.h>

Inheritance diagram for FDragDropOperation:

Public Member Functions
SLATECORE_API	FDragDropOperation ()
virtual SLATECORE_API	~FDragDropOperation ()
template<class TType >
bool	IsOfType () const
virtual bool	AffectedByPointerEvent (const FPointerEvent &PointerEvent)
virtual SLATECORE_API void	OnDrop (bool bDropWasHandled, const FPointerEvent &MouseEvent)
virtual SLATECORE_API void	OnDragged (const class FDragDropEvent &DragDropEvent)
virtual SLATECORE_API FCursorReply	OnCursorQuery ()
virtual TSharedPtr< SWidget >	GetDefaultDecorator () const
virtual FVector2D	GetDecoratorPosition () const
virtual SLATECORE_API void	SetDecoratorVisibility (bool bVisible)
virtual bool	IsExternalOperation () const
virtual bool	IsWindowlessOperation () const
SLATECORE_API void	SetCursorOverride (TOptional< EMouseCursor::Type > CursorType)
virtual bool	IsOfTypeImpl (const FString &Type) const
Public Member Functions inherited from TSharedFromThis< FDragDropOperation >
TSharedRef< FDragDropOperation, Mode >	AsShared ()
TSharedRef< FDragDropOperation const, Mode >	AsShared () const
TSharedRef< SubobjectType, Mode >	AsSharedSubobject (SubobjectType *SubobjectPtr) const
TWeakPtr< FDragDropOperation, Mode >	AsWeak ()
TWeakPtr< FDragDropOperation const, Mode >	AsWeak () const
TWeakPtr< SubobjectType, Mode >	AsWeakSubobject (SubobjectType *SubobjectPtr) const
void	UpdateWeakReferenceInternal (TSharedPtr< SharedPtrType, SharedPtrMode > const *InSharedPtr, OtherType *InObject) const
void	UpdateWeakReferenceInternal (TSharedRef< SharedRefType, SharedPtrMode > const *InSharedRef, OtherType *InObject) const
UE_FORCEINLINE_HINT bool	DoesSharedInstanceExist () const

Protected Member Functions
virtual SLATECORE_API void	Construct ()
SLATECORE_API void	CreateCursorDecoratorWindow ()
SLATECORE_API void	DestroyCursorDecoratorWindow ()
virtual TSharedPtr< FDragDropOperation >	ConvertTo (const FString &TypeId)
Protected Member Functions inherited from TSharedFromThis< FDragDropOperation >
	TSharedFromThis ()
	TSharedFromThis (TSharedFromThis const &)
UE_FORCEINLINE_HINT TSharedFromThis &	operator= (TSharedFromThis const &)
	~TSharedFromThis ()

Protected Attributes
bool	bCreateNewWindow
TSharedPtr< SWindow >	CursorDecoratorWindow
TOptional< EMouseCursor::Type >	MouseCursor
TOptional< EMouseCursor::Type >	MouseCursorOverride

Additional Inherited Members
Static Protected Member Functions inherited from TSharedFromThis< FDragDropOperation >
static UE_FORCEINLINE_HINT TSharedRef< OtherType, Mode >	SharedThis (OtherType *ThisPtr)
static UE_FORCEINLINE_HINT TSharedRef< OtherType const, Mode >	SharedThis (const OtherType *ThisPtr)

Detailed Description

A base class for a DragAndDrop operation which supports reflection. Drag and Drop is inherently quite stateful. Implementing a custom DragDropOperation allows for dedicated handling of a drag drop operation which keeps a decorator window (optionally) Implement derived types with DRAG_DROP_OPERATOR_TYPE (see below)

Constructor & Destructor Documentation

FDragDropOperation()

FDragDropOperation::FDragDropOperation

(

)

Default constructor.

~FDragDropOperation()

FDragDropOperation::~FDragDropOperation ( )

virtual

Destructor.

Member Function Documentation

AffectedByPointerEvent()

virtual bool FDragDropOperation::AffectedByPointerEvent ( const FPointerEvent &  PointerEvent )

inlinevirtual

Checks if this drag and drop operation is affected by a given PointerEvent.

Parameters

PointerEvent

The mouse event we are checking against

Returns

true if the the pointer event affects this drag and drop operation (default true).

Reimplemented in FUMGDragDropOp.

Construct()

void FDragDropOperation::Construct ( )

protectedvirtual

Constructs the window and widget if applicable.

Reimplemented in FUMGDragDropOp.

ConvertTo()

virtual TSharedPtr< FDragDropOperation > FDragDropOperation::ConvertTo ( const FString &  TypeId )

inlineprotectedvirtual

CreateCursorDecoratorWindow()

void FDragDropOperation::CreateCursorDecoratorWindow ( )

protected

Creates a window for the cursor decorator.

DestroyCursorDecoratorWindow()

void FDragDropOperation::DestroyCursorDecoratorWindow ( )

protected

Destroys the cursor decorator window.

GetDecoratorPosition()

virtual FVector2D FDragDropOperation::GetDecoratorPosition ( ) const

inlinevirtual

Gets the desired position of the decorator in absolute space.

Reimplemented in FGameDragDropOperation.

GetDefaultDecorator()

virtual TSharedPtr< SWidget > FDragDropOperation::GetDefaultDecorator ( ) const

inlinevirtual

Gets the widget that will serve as the decorator unless overridden. If you do not override, you will have no decorator

Reimplemented in FUICommandDragDropOp, and FUMGDragDropOp.

IsExternalOperation()

virtual bool FDragDropOperation::IsExternalOperation ( ) const

inlinevirtual

Is this drag Drop operation going to interact with applications outside of Slate

IsOfType()

template<class TType >

bool FDragDropOperation::IsOfType ( ) const

inline

Check if this drag and drop operation can cast safely to the specified template type

IsOfTypeImpl()

virtual bool FDragDropOperation::IsOfTypeImpl ( const FString &  Type ) const

inlinevirtual

Checks whether this drag and drop operation can cast safely to the specified type.

IsWindowlessOperation()

virtual bool FDragDropOperation::IsWindowlessOperation ( ) const

inlinevirtual

Returns

true if the operation does not create a decorator window. Used for game drag drop operations.

OnCursorQuery()

FCursorReply FDragDropOperation::OnCursorQuery ( )

virtual

Allows drag/drop operations to override the current cursor

Reimplemented in FUMGDragDropOp.

OnDragged()

void FDragDropOperation::OnDragged ( const class FDragDropEvent &  DragDropEvent )

virtual

Called when the mouse was moved during a drag and drop operation

Parameters

DragDropEvent

The event that describes this drag drop operation.

Reimplemented in FUICommandDragDropOp, and FUMGDragDropOp.

OnDrop()

void FDragDropOperation::OnDrop ( bool  bDropWasHandled, const FPointerEvent &  MouseEvent  )

virtual

Invoked when the drag and drop operation has ended.

Parameters

bDropWasHandled	true when the drop was handled by some widget; false otherwise
MouseEvent	The mouse event which caused the on drop to be called.

Reimplemented in FDockingDragOperation, FUICommandDragDropOp, and FUMGDragDropOp.

SetCursorOverride()

void FDragDropOperation::SetCursorOverride

(

TOptional< EMouseCursor::Type >

CursorType

)

Sets the cursor to override the drag drop operations cursor with so that a control can give temporary feedback, for example - a slashed circle telling the user 'this can't be dropped here'.

SetDecoratorVisibility()

void FDragDropOperation::SetDecoratorVisibility ( bool  bVisible )

virtual

Alters the visibility of the window

Member Data Documentation

bCreateNewWindow

bool FDragDropOperation::bCreateNewWindow

protected

Create a new window for the decorator content. If this is false, SlateApplication will draw the decorator directly using the

CursorDecoratorWindow

TSharedPtr<SWindow> FDragDropOperation::CursorDecoratorWindow

protected

The window that owns the decorator widget

MouseCursor

TOptional<EMouseCursor::Type> FDragDropOperation::MouseCursor

protected

Mouse cursor used by the drag drop operation

MouseCursorOverride

TOptional<EMouseCursor::Type> FDragDropOperation::MouseCursorOverride

protected

Mouse cursor used to temporarily replace the drag drops cursor

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The documentation for this class was generated from the following files:

• Engine/Source/Runtime/SlateCore/Public/Input/DragAndDrop.h
• Engine/Source/Runtime/SlateCore/Private/Input/DragAndDrop.cpp