FScrollyZoomy Class Reference

#include <ScrollyZoomy.h>

Public Member Functions
SLATE_API	FScrollyZoomy (const bool InUseInertialScrolling=true)
SLATE_API void	Tick (const float DeltaTime, IScrollableZoomable &ScrollableZoomable)
SLATE_API FReply	OnMouseButtonDown (const FPointerEvent &MouseEvent)
SLATE_API FReply	OnMouseButtonUp (const TSharedRef< SWidget > MyWidget, const FGeometry &MyGeometry, const FPointerEvent &MouseEvent)
SLATE_API FReply	OnMouseMove (const TSharedRef< SWidget > MyWidget, IScrollableZoomable &ScrollableZoomable, const FGeometry &MyGeometry, const FPointerEvent &MouseEvent)
SLATE_API void	OnMouseLeave (const TSharedRef< SWidget > MyWidget, const FPointerEvent &MouseEvent)
SLATE_API FReply	OnMouseWheel (const FPointerEvent &MouseEvent, IScrollableZoomable &ScrollableZoomable)
SLATE_API FCursorReply	OnCursorQuery () const
SLATE_API bool	IsRightClickScrolling () const
SLATE_API bool	NeedsSoftwareCursor () const
SLATE_API UE::Slate::FDeprecateVector2DResult	GetSoftwareCursorPosition () const
SLATE_API int32	PaintSoftwareCursorIfNeeded (const FGeometry &AllottedGeometry, const FSlateRect &MyCullingRect, FSlateWindowElementList &OutDrawElements, int32 LayerId) const

Detailed Description

Utility class that adds scrolling and zooming functionality to a widget.

Derived your widget class from IScrollableZoomable, then embed an instance of FScrollyZoomy as a widget member variable, and call this class's event handlers from your own widget's event handler callbacks.

Constructor & Destructor Documentation

FScrollyZoomy()

FScrollyZoomy::FScrollyZoomy

(

const bool

InUseInertialScrolling = true

)

Create and initialize a new instance.

Parameters

InUseInertialScrolling

Whether inertial scrolling should be used (default = true).

Member Function Documentation

GetSoftwareCursorPosition()

UE::Slate::FDeprecateVector2DResult FScrollyZoomy::GetSoftwareCursorPosition

(

)

const

Get the position of the software cursor (when NeedsSoftwareCursor is true).

This method should be called from your widget's OnPaint function.

Returns

Cursor position.

See also

NeedsSoftwareCursor

IsRightClickScrolling()

bool FScrollyZoomy::IsRightClickScrolling

(

)

const

Whether the user is actively scrolling.

Returns

true if the user is scrolling, false otherwise.

NeedsSoftwareCursor()

bool FScrollyZoomy::NeedsSoftwareCursor

(

)

const

Whether a software cursor should be rendered.

This method should be called from your widget's OnPaint function.

Returns

true if a software cursor should be rendered, false otherwise.

See also

GetSoftwareCursorPosition

OnCursorQuery()

FCursorReply FScrollyZoomy::OnCursorQuery

(

)

const

Call this from your widget's OnCursorQuery function.

Returns

The cursor reply to pass back.

OnMouseButtonDown()

FReply FScrollyZoomy::OnMouseButtonDown

(

const FPointerEvent &

MouseEvent

)

Should be called when a mouse button is pressed.

Parameters

MouseEvent

The mouse event passed to a widget's OnMouseButtonDown function.

Returns

If FReply::Handled is returned, that should be passed as the result of the calling function.

OnMouseButtonUp()

FReply FScrollyZoomy::OnMouseButtonUp	(	const TSharedRef< SWidget >	MyWidget,
		const FGeometry &	MyGeometry,
		const FPointerEvent &	MouseEvent
	)

Should be called when a mouse button is released.

Parameters

MyWidget	Pointer to the widget that owns this object.
MyGeometry	Geometry of the widget we're scrolling.
MouseEvent	The mouse event passed to a widget's OnMouseButtonUp function.

Returns

If FReply::Handled is returned, that should be passed as the result of the calling function.

OnMouseLeave()

void FScrollyZoomy::OnMouseLeave	(	const TSharedRef< SWidget >	MyWidget,
		const FPointerEvent &	MouseEvent
	)

Should be called from your widget's OnMouseLeave override.

Parameters

MyWidget	Pointer to the widget that owns this object.
MouseEvent	The mouse leave event that was passed to the widget's OnMouseLeave function.

OnMouseMove()

FReply FScrollyZoomy::OnMouseMove	(	const TSharedRef< SWidget >	MyWidget,
		IScrollableZoomable &	ScrollableZoomable,
		const FGeometry &	MyGeometry,
		const FPointerEvent &	MouseEvent
	)

Should be called when a mouse move event occurs.

Parameters

MyWidget	Pointer to the widget that owns this object.
ScrollableZoomable	Interface to the widget to scroll/zoom.
MyGeometry	Geometry of the widget we're scrolling.
MouseEvent	The mouse event passed to a widget's OnMouseMove function.

Returns

If FReply::Handled is returned, that should be passed as the result of the calling function.

OnMouseWheel()

FReply FScrollyZoomy::OnMouseWheel	(	const FPointerEvent &	MouseEvent,
		IScrollableZoomable &	ScrollableZoomable
	)

Should be called by your widget when the mouse wheel is used

Parameters

MouseEvent	The event passed to your widget's OnMouseWheel function.
ScrollableZoomable	Interface to the widget to scroll/zoom.

Returns

If FReply::Handled is returned, that should be passed as the result of the calling function.

PaintSoftwareCursorIfNeeded()

int32 FScrollyZoomy::PaintSoftwareCursorIfNeeded	(	const FGeometry &	AllottedGeometry,
		const FSlateRect &	MyCullingRect,
		FSlateWindowElementList &	OutDrawElements,
		int32	LayerId
	)		const

Call this from your widget's OnPaint to paint a software cursor, if needed

Parameters

AllottedGeometry	Widget geometry passed into OnPaint.
MyCullingRect	Widget clipping rect passed into OnPaint.
OutDrawElements	The draw element list.
LayerId	Layer identifier.

Returns

New layer Identifier.

Tick()

void FScrollyZoomy::Tick	(	const float	DeltaTime,
		IScrollableZoomable &	ScrollableZoomable
	)

Should be called every frame to update simulation state.

Parameters

DeltaTime	Time that's passed.
ScrollableZoomable	Interface to the widget to scroll/zoom.

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

• Engine/Source/Runtime/Slate/Public/Framework/Layout/ScrollyZoomy.h
• Engine/Source/Runtime/Slate/Private/Framework/Layout/ScrollyZoomy.cpp