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SWidget

HOW TO DEPRECATE SLATE_ATTRIBUTES

API > API/Runtime > API/Runtime/SlateCore > API/Runtime/SlateCore/Widgets

Inheritance Hierarchy

References

   
Module SlateCore
Header /Engine/Source/Runtime/SlateCore/Public/Widgets/SWidget.h
Include #include "Widgets/SWidget.h"

Syntax

class SWidget :  
    public FSlateControlledConstruction ,  
    public TSharedFromThis< SWidget >

Remarks

HOW TO DEPRECATE SLATE_ATTRIBUTES

SLATE_ATTRIBUTE(ECheckBoxState, IsChecked)

UE_DEPRECATED(4.xx, "Please use IsChecked(TAttribute)") FArguments& IsChecked(bool InIsChecked) { _IsChecked = InIsChecked ? ECheckBoxState::Checked : ECheckBoxState::Unchecked; return Me(); }

// This version would prevent ambiguous conversions. FArguments& IsChecked(ECheckBoxState InIsChecked) { _IsChecked = InIsChecked; return Me(); } Abstract base class for Slate widgets.

STOP. DO NOT INHERIT DIRECTLY FROM WIDGET!

Inheritance: Widget is not meant to be directly inherited. Instead consider inheriting from LeafWidget or Panel, which represent intended use cases and provide a succinct set of methods which to override.

SWidget is the base class for all interactive Slate entities. SWidget's public interface describes everything that a Widget can do and is fairly complex as a result.

Events: Events in Slate are implemented as virtual functions that the Slate system will call on a Widget in order to notify the Widget about an important occurrence (e.g. a key press) or querying the Widget regarding some information (e.g. what mouse cursor should be displayed).

Widget provides a default implementation for most events; the default implementation does nothing and does not handle the event.

Some events are able to reply to the system by returning an FReply, FCursorReply, or similar object.

Variables

  Type Name Description
Protected variable uint8: 1 bCanHaveChildren Can the widget ever support children? This will be false on SLeafWidgets, rather than setting this directly, you should probably inherit from SLeafWidget.
Protected variable uint8: 1 bCanSupportFocus Can the widget ever support keyboard focus
Protected variable uint8: 1 bClippingProxy Some widgets might be a complex hierarchy of child widgets you never see.
Protected variable uint8: 1 bHasCustomPrepass  
Protected variable uint8: 1 bHasRelativeLayoutScale  
Protected variable uint8: 1 bVolatilityAlwaysInvalidatesPrepass If this widget should always invalidate the prepass step when volatile
Protected variable EWidgetClipping Clipping Set to true if all content of the widget should clip to the bounds of this widget.
Protected variable FMargin CullingBoundsExtension Can be used to enlarge the culling bounds of this widget (pre-intersection), this can be useful if you've got children that you know are using rendering transforms to render outside their standard bounds, if that happens it's possible the parent might be culled before the descendant widget is entirely off screen.
Protected variable EWidgetPixelSnapping PixelSnappingMethod When set to EPixelSnappingMethod::SnapToPixel, the widget is drawn at the nearest pixel.
Protected variable TOptional< float > PrepassLayoutScaleMultiplier  
Protected variable float RenderOpacity The opacity of the widget. Automatically applied during rendering.

Constructors

  Type Name Description
Protected function  

SWidget ()

 Hidden default constructor.Use SNew(WidgetClassName) to instantiate new widgets.

Destructors

  Type Name Description
Protected function Virtual   Dtor ensures that active timer handles are UnRegistered with the SlateApplication.

Functions

  Type Name Description
Protected function Static TAttribute< EVisibility > Protected static helper to allow widgets to access the visibility attribute of other widgets directly
Public function void

AddMetadata ( const TSharedRef< MetaDataType >& AddMe
)

 Add metadata to this widget.
Public function Virtual Const const FSlateInvalidationRoot *  
Public function Const TSharedPtr< SWidget >  
Protected function bool Recalculates and caches volatility and returns 'true' if the volatility changed.
Public function Virtual Const bool  
Public function Virtual Const bool Is this widget derivative of SWindow
Public function Const void

ArrangeChildren ( const FGeometry& AllottedGeometry,
FArrangedChildren& ArrangedChildren,
bool bUpdateAttributes
)

 Non-virtual entry point for arrange children.
Public function void  
Protected function Virtual void

CacheDesiredSize ( float InLayoutScaleMultiplier
)

 The system calls this method.
Public function void Recalculates volatility of the widget and caches the result.
Public function Const FSlateRect

CalculateCullingAndClippingRules ( const FGeometry& AllottedGeometry,
const FSlateRect& MyCullingRect,
bool& bClipToBounds,
bool& bAlwaysClip,
bool& bIntersectClipBounds
)

 Calculates what if any clipping state changes need to happen when drawing this widget.
Protected function Const FVector2D

ComputeDesiredSize ( float LayoutScaleMultiplier
)

 Compute the ideal size necessary to display this widget.
Protected function Const EFlowDirection Establishes a new flow direction potentially, if this widget has a particular preference for it and all its children.
Protected function Virtual Const bool Recomputes the volatility of the widget.
Public function bool  
Protected function Virtual bool

CustomPrepass ( float LayoutScaleMultiplier
)

  
Public function Virtual FChildren * Returns all Widgets, including widget hidden from the invalidation system.
Public function Const uint32  
Public function void

EnableToolTipForceField ( const bool bEnableForceField
)

 Sets whether this widget is a "tool tip force field".
Protected function Const bool

FindChildGeometries ( const FGeometry& MyGeometry,
const TSet< TSharedRef< SWidget > >& WidgetsToFind,
TMap< TSharedRef< SWidget >, FArrangedWidget >& OutResult
)

 Find the geometry of a descendant widget.
Protected function Const void

FindChildGeometries_Helper ( const FGeometry& MyGeometry,
const TSet< TSharedRef< SWidget > >& WidgetsToFind,
TMap< TSharedRef< SWidget >, FArrangedWidget >& OutResult
)

 Actual implementation of FindChildGeometries.
Protected function Const FGeometry

FindChildGeometry ( const FGeometry& MyGeometry,
TSharedRef< SWidget > WidgetToFind
)

 Find the geometry of a descendant widget.
Protected function Static int32

FindChildUnderMouse ( const FArrangedChildren& Children,
const FPointerEvent& MouseEvent
)

  
Protected function Static int32

FindChildUnderPosition ( const FArrangedChildren& Children,
const UE::Slate::FDeprecateVector2DParameter& ArrangedSpacePosition
)

  
Public function void

ForceVolatile ( bool bForce
)

 Should this widget always appear as volatile for any layout caching host widget.
Public function Virtual FChildren * Returns the children (if any) of this widget that are used by the invalidation system.
Public function Const TArray< TSharedRef< MetaDataType > > Get all metadata of the type provided.
Public function Const const FGeometry &  
Public function Const bool  
Public function FChildren * Returns the useful children (if any) of this widget.
Public function Const EWidgetClipping  
Public function Const FName  
Public function Const FMargin  
Public function Const const TOptional< FSlateClippingState > & Returns the clipping state to clip this widget against its parent
Protected function Virtual Const TOptional< EMouseCursor::Type > The cursor to show when the mouse is hovering over this widget.
Public function Const UE::Slate::FDeprecateVector2DResult  
Public function Virtual Const FSlateColor  
Protected function Const TSlateAttributeRef< bool >  
Public function Const EFlowDirectionPreference Gets the desired flow direction for the layout.
Protected function Virtual Const const FSlateBrush *  
Public function Virtual Const FSlateColor  
Protected function Const TSlateAttributeRef< bool >  
Public function Const uint64

GetId ()

  
Public function Const TSharedPtr< MetaDataType > Get the metadata of the type provided.
Public function Const const FGeometry & Gets the last geometry used to Tick the widget.
Public function Const TSharedPtr< SWidget >  
Public function Const const FSlateWidgetPersistentState &  
Public function Const EWidgetPixelSnapping  
Protected function Const float  
Public function Const const FWidgetProxyHandle  
Public function Virtual Const FString  
Public function Virtual Const float

GetRelativeLayoutScale ( const int32 ChildIndex,
float LayoutScaleMultiplier
)

 What is the Child's scale relative to this widget.
Public function Const float  
Public function Const const TOptional< FSlateRenderTransform > &  
Protected function Const TSlateAttributeRef< TOptional< FSlateRenderTransform > >  
Public function Const UE::Slate::FDeprecateVector2DResult  
Protected function Const TSlateAttributeRef< FVector2D >  
Public function Const UE::Slate::FDeprecateVector2DResult  
Public function Const TOptional< FSlateRenderTransform >  
Public function Const TStatId

GetStatID ( bool bForDeferredUse
)

  
Public function Virtual Const FName

GetTag ()

  
Public function Const const FGeometry & Gets the last geometry used to Tick the widget.
Public function Virtual TSharedPtr< IToolTip >  
Public function Const FName

GetType ()

  
Public function Const FString  
Public function Const EVisibility This widget can be visible but if a parent is hidden or collapsed, it would not show on screen.
Protected function Const TSlateAttributeRef< EVisibility >  
Public function Virtual Const EWindowZone::Type Called when the mouse is moved over the widget's window, to determine if we should report whether OS-specific features should be active at this location (such as a title bar grip, system menu, etc.) Usually you should not need to override this function.
Public function Const bool Does this widget have any active timers?
Public function Const bool  
Public function Const TOptional< EFocusCause > Gets whether or not any users have this widget focused, and if so the type of focus (first one found).
Public function Const bool  
Public function Const bool  
Public function Virtual Const bool Checks to see if this widget currently has the keyboard focus
Public function Const bool Checks to see if this widget is the current mouse captor
Public function Const bool

HasMouseCaptureByUser ( int32 UserIndex,
TOptional< int32 > PointerIndex
)

 Checks to see if this widget has mouse capture from the provided user.
Public function Const bool  
Public function Const bool  
Public function Const TOptional< EFocusCause >

HasUserFocus ( int32 UserIndex
)

 Gets whether or not the specified users has this widget focused, and if so the type of focus.
Public function Const bool Gets whether or not the specified users has this widget or any descendant focused.
Public function void

Invalidate ( EInvalidateWidgetReason InvalidateReason
)

 Invalidates the widget from the view of a layout caching widget that may own this widget.
Protected function void Called when a child is removed from the tree parent's widget tree either by removing it from a slot.
Public function Const bool  
Protected function Const bool

IsChildWidgetCulled ( const FSlateRect& MyCullingRect,
const FArrangedWidget& ArrangedChild
)

 Tests if an arranged widget should be culled.
Protected function Const bool Is the widget construction completed (did we called and returned from the Construct() function)
Public function Const bool  
Public function Const bool  
Public function Const bool IsHovered used to be virtual.
Public function Virtual Const bool  
Public function Const bool  
Public function Const bool Whether or not a widget is volatile and will update every frame without being invalidated
Public function Const bool This widget is volatile because its parent or some ancestor is volatile
Public function void In fast path, if the widget is mark, do a full Prepass on its next update to calculate it's desired size.
Public function Const bool LAYOUT
Public function Virtual FReply

OnAnalogValueChanged ( const FGeometry& MyGeometry,
const FAnalogInputEvent& InAnalogInputEvent
)

 Called when an analog value changes on a button that supports analog
Protected function Virtual void Called when clipping is changed.
Public function Virtual Const FCursorReply

OnCursorQuery ( const FGeometry& MyGeometry,
const FPointerEvent& CursorEvent
)

 The system asks each widget under the mouse to provide a cursor. This event is bubbled.
Public function Virtual FReply

OnDragDetected ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 Called when Slate detects that a widget started to be dragged.
Public function Virtual void

OnDragEnter ( const FGeometry& MyGeometry,
const FDragDropEvent& DragDropEvent
)

 DRAG AND DROP (DragDrop) Called during drag and drop when the drag enters a widget.
Public function Virtual void

OnDragLeave ( const FDragDropEvent& DragDropEvent
)

 Called during drag and drop when the drag leaves a widget.
Public function Virtual FReply

OnDragOver ( const FGeometry& MyGeometry,
const FDragDropEvent& DragDropEvent
)

 Called during drag and drop when the the mouse is being dragged over a widget.
Public function Virtual FReply

OnDrop ( const FGeometry& MyGeometry,
const FDragDropEvent& DragDropEvent
)

 Called when the user is dropping something onto a widget; terminates drag and drop.
Public function Virtual void All the key (keyboard, gamepay, joystick, etc.) input from this frame has been routed.
Public function Virtual void All the pointer (mouse, touch, stylus, etc.) events from this frame have been routed.
Public function Virtual void

OnFocusChanging ( const FWeakWidgetPath& PreviousFocusPath,
const FWidgetPath& NewWidgetPath,
const FFocusEvent& InFocusEvent
)

 Called whenever a focus path is changing on all the widgets within the old and new focus paths
Public function Virtual void

OnFocusLost ( const FFocusEvent& InFocusEvent
)

 Called when this widget loses focus. This event does not bubble.
Public function Virtual FReply

OnFocusReceived ( const FGeometry& MyGeometry,
const FFocusEvent& InFocusEvent
)

 KEY INPUT Called when focus is given to this widget. This event does not bubble.
Public function Virtual FReply

OnKeyChar ( const FGeometry& MyGeometry,
const FCharacterEvent& InCharacterEvent
)

 Called after a character is entered while this widget has keyboard focus
Public function Virtual FReply

OnKeyDown ( const FGeometry& MyGeometry,
const FKeyEvent& InKeyEvent
)

 Called after a key is pressed when this widget has focus (this event bubbles if not handled)
Public function Virtual FReply

OnKeyUp ( const FGeometry& MyGeometry,
const FKeyEvent& InKeyEvent
)

 Called after a key is released when this widget has focus
Public function Virtual Const TOptional< TSharedRef< SWidget > >

OnMapCursor ( const FCursorReply& CursorReply
)

 After OnCursorQuery has specified a cursor type the system asks each widget under the mouse to map that cursor to a widget.
Public function Virtual FReply

OnMotionDetected ( const FGeometry& MyGeometry,
const FMotionEvent& InMotionEvent
)

 Called when motion is detected (controller or device) e.g. Someone tilts or shakes their controller.
Public function Virtual FReply

OnMouseButtonDoubleClick ( const FGeometry& InMyGeometry,
const FPointerEvent& InMouseEvent
)

 Called when a mouse button is double clicked. Override this in derived classes.
Public function Virtual FReply

OnMouseButtonDown ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 MOUSE INPUT The system calls this method to notify the widget that a mouse button was pressed within it.
Public function Virtual FReply

OnMouseButtonUp ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 The system calls this method to notify the widget that a mouse button was release within it.
Public function Virtual void

OnMouseCaptureLost ( const FCaptureLostEvent& CaptureLostEvent
)

 Called when this widget had captured the mouse, but that capture has been revoked for some reason.
Public function Virtual void

OnMouseEnter ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 The system will use this event to notify a widget that the cursor has entered it.
Public function Virtual void

OnMouseLeave ( const FPointerEvent& MouseEvent
)

 The system will use this event to notify a widget that the cursor has left it.
Public function Virtual FReply

OnMouseMove ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 The system calls this method to notify the widget that a mouse moved within it.
Public function Virtual FReply

OnMouseWheel ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 Called when the mouse wheel is spun. This event is bubbled.
Public function Virtual FNavigationReply

OnNavigation ( const FGeometry& MyGeometry,
const FNavigationEvent& InNavigationEvent
)

 Called when navigation is requested e.g. Left Joystick, Direction Pad, Arrow Keys can generate navigation events.
Public function Virtual FReply

OnPreviewKeyDown ( const FGeometry& MyGeometry,
const FKeyEvent& InKeyEvent
)

 Called after a key is pressed when this widget or a child of this widget has focus If a widget handles this event, OnKeyDown will not be passed to the focused widget.
Public function Virtual FReply

OnPreviewMouseButtonDown ( const FGeometry& MyGeometry,
const FPointerEvent& MouseEvent
)

 Just like OnMouseButtonDown, but tunnels instead of bubbling.
Public function Virtual Const FPopupMethodReply Popups can manifest in a NEW OS WINDOW or via an OVERLAY in an existing window.
Public function Virtual Const TOptional< bool >

OnQueryShowFocus ( const EFocusCause InFocusCause
)

 Called to determine if we should render the focus brush.
Public function Virtual void Called when a tooltip displayed from this widget is being closed
Public function Virtual FReply

OnTouchEnded ( const FGeometry& MyGeometry,
const FPointerEvent& InTouchEvent
)

 Called when a touchpad touch is ended (finger lifted)
Public function Virtual FReply

OnTouchFirstMove ( const FGeometry& MyGeometry,
const FPointerEvent& TouchEvent
)

 Called when a touchpad touch first moves after TouchStarted
Public function Virtual FReply

OnTouchForceChanged ( const FGeometry& MyGeometry,
const FPointerEvent& TouchEvent
)

 Called when a touchpad touch force changes
Public function Virtual FReply

OnTouchGesture ( const FGeometry& MyGeometry,
const FPointerEvent& GestureEvent
)

 TOUCH and GESTURES Called when the user performs a gesture on trackpad. This event is bubbled.
Public function Virtual FReply

OnTouchMoved ( const FGeometry& MyGeometry,
const FPointerEvent& InTouchEvent
)

 Called when a touchpad touch is moved (finger moved)
Public function Virtual FReply

OnTouchStarted ( const FGeometry& MyGeometry,
const FPointerEvent& InTouchEvent
)

 Called when a touchpad touch is started (finger down)
Public function Virtual TSharedPtr< FPopupLayer >

OnVisualizePopup ( const TSharedRef< SWidget >& PopupContent
)

 Visualize a new pop-up if possible.
Public function Virtual bool

OnVisualizeTooltip ( const TSharedPtr< SWidget >& TooltipContent
)

 Called when Slate wants to visualize tooltip.
Public function Const int32

Paint ( const FPaintArgs& Args,
const FGeometry& AllottedGeometry,
const FSlateRect& MyCullingRect,
FSlateWindowElementList& OutDrawElements,
int32 LayerId,
const FWidgetStyle& InWidgetStyle,
bool bParentEnabled
)

 GENERAL EVENTS Called to tell a widget to paint itself (and it's children).
Protected function void

Prepass_ChildLoop ( float InLayoutScaleMultiplier,
FChildren* MyChildren
)

  
Public function TSharedRef< FActiveTimerHandle >

RegisterActiveTimer ( float TickPeriod,
FWidgetActiveTimerDelegate TickFunction
)

 Registers an "active timer" delegate that will execute at some regular interval.
Public function int32

RemoveMetaData ( const TSharedRef< MetaDataType >& RemoveMe
)

 Remove metadata to this widget.
Protected function bool

SetAttribute ( TAttribute< TargetValueType >& TargetValue,
const TAttribute< SourceValueType >& SourceValue,
EInvalidateWidgetReason BaseInvalidationReason
)

 Performs the attribute assignment and invalidates the widget minimally based on what actually changed.
Public function void

SetCanTick ( bool bInCanTick
)

  
Public function void

SetClipping ( EWidgetClipping InClipping
)

 Sets the clipping to bounds rules for this widget.
Public function void

SetCullingBoundsExtension ( const FMargin& InCullingBoundsExtension
)

 Sets an additional culling padding that is added to a widget to give more leeway when culling widgets.
Public function void

SetCursor ( const TAttribute< TOptional< EMouseCursor::Type > >& InCursor
)

 Set the cursor that should appear when this widget is hovered
Protected function void

SetDebugInfo ( const ANSICHAR* InType,
const ANSICHAR* InFile,
int32 OnLine,
size_t InAllocSize
)

 Used by Slate to set the runtime debug info about this widget.
Public function void

SetEnabled ( TAttribute< bool > InEnabledState
)

 Sets the enabled state of this widget
Public function void Sets how content should flow in this panel, based on the current culture.
Protected function void

SetHover ( TAttribute< bool > InHovered
)

 Set the hover state.
Public function void See OnMouseButtonDown event
Public function void See OnMouseButtonUp event
Public function void See OnMouseDoubleClick event
Public function void See OnMouseEnter event
Public function void See OnMouseLeave event
Public function void See OnMouseMove event
Public function void

SetPixelSnapping ( EWidgetPixelSnapping InPixelSnappingMethod
)

 Sets the pixel snapping method for this widget.
Public function void

SetRenderOpacity ( float InRenderOpacity
)

  
Public function void  
Public function void

SetRenderTransformPivot ( TAttribute< FVector2D > InTransformPivot
)

  
Public function void

SetTag ( FName InTag
)

  
Public function void

SetToolTip ( const TAttribute< TSharedPtr< IToolTip > >& InToolTip
)

 Set the tool tip that should appear when this widget is hovered.
Public function void

SetToolTipText ( const FText& InToolTipText
)

 Set the tool tip that should appear when this widget is hovered.
Public function void

SetToolTipText ( const TAttribute< FText >& ToolTipText
)

 Set the tool tip that should appear when this widget is hovered.
Public function Virtual void

SetVisibility ( TAttribute< EVisibility > InVisibility
)

  
Protected function void

SetVolatilePrepass ( bool bVolatile
)

  
Protected function Const bool

ShouldBeEnabled ( bool InParentEnabled
)

 Determines if this widget should be enabled.
Public function bool  
Public function void DEPRECATED version of SlatePrepass that assumes no scaling beyond AppScale
Public function void

SlatePrepass ( float InLayoutScaleMultiplier
)

 Descends to leaf-most widgets in the hierarchy and gathers desired sizes on the way up.
Public function Static const FSlateWidgetClassData &  
Public function Virtual Const bool Checks to see if this widget supports keyboard focus. Override this in derived classes.
Protected function void Construct a SWidget based on initial parameters.
Public function Virtual void

Tick ( const FGeometry& AllottedGeometry,
const double InCurrentTime,
const float InDeltaTime
)

 Ticks this widget with Geometry.
Public function Virtual Const FString  
Public function Virtual Const TOptional< FVirtualPointerPosition >

TranslateMouseCoordinateForCustomHitTestChild ( const SWidget& ChildWidget,
const FGeometry& MyGeometry,
const FVector2D ScreenSpaceMouseCoordinate,
const FVector2D LastScreenSpaceMouseCoordinate
)

  
Public function void

UnRegisterActiveTimer ( const TSharedRef< FActiveTimerHandle >& ActiveTimerHandle
)

 Unregisters an active timer handle.
Public function Virtual bool  

Overridden from FSlateControlledConstruction

  Type Name Description
Public function Virtual Const const FSlateWidgetClassData &  

Classes

  Type Name Description
Protected struct TSlateAttribute A SlateAttribute that is member variable of a SWidget.  
Protected struct TSlateAttribute< FText, InInvalidationReasonValue >    
Protected struct TSlateAttributeRef A Reference to a TSlateAttribute.  
Protected struct TSlateAttributeRef< FText, InInvalidationReasonValue >    
Protected struct TSlateManagedAttribute A SlateAttribute that is NOT a member variable of a SWidget.  
Protected struct TSlateManagedAttribute< FText, InInvalidationReasonValue >    

Typedefs

Name Description
PrivateParentType  
PrivateThisType  
Super  
ThisClass  

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