USingleClickAndDragBehavior

USingleClickAndDragInputBehavior implements a combination of "button-click" and "button-click-drag"-style input behavior.

API > API/Editor > API/Editor/EditorInteractiveToolsFramework

USingleClickAndDragInputBehavior implements a combination of "button-click" and "button-click-drag"-style input behavior. If the mouse is moved away from the original location, and update will occur and a drag operation will start. If the mouse is released without moving too far away, a click event will occur. Once the drag has started, returning to the original location will not produce a click event will not be produced, but the drag operation will continue.

NOTE: This differs from USingleClickOrDragInputBehavior in that it provides a separate call sequence for click and drag: Single Clicks: OnClickPress OnClickRelease

Drag: OnDragStarted OnClickDrag

An ISingleClickAndDragBehaviorTarget instance must be provided which is manipulated by this behavior.

The state machine works as follows: 1) on input-device-button-press, call Target::CanBeginSingleClickDragSequence to determine if capture should begin 2) on input-device-move, call Target::OnClickDrag if drag mode has been started or Target::OnDragStart if it crosses that threshold. 3) on input-device-button-release, call Target::OnClickRelease

If a ForceEndCapture occurs we call Target::OnTerminateDragClickSequence

   
Name USingleClickAndDragBehavior
Type class
Header File /Engine/Source/Editor/Experimental/EditorInteractiveToolsFramework/Public/Behaviors/SingleClickAndDragBehavior.h
Include Path #include "Behaviors/SingleClickAndDragBehavior.h"

Syntax

UCLASS (MinimalAPI)  
class USingleClickAndDragBehavior : public UAnyButtonInputBehavior

Inheritance Hierarchy

Derived Classes

Variables

Public

Name Type Remarks Include Path Unreal Specifiers
bBeginDragIfClickTargetNotHit bool If true (default), then if the click-mouse-down does not hit a valid click target (determined by IClickBehaviorTarget::IsHitByClick), then the Drag will be initiated Behaviors/SingleClickAndDragBehavior.h  
DragDistanceThreshold float If the device moves more than this distance in 2D (pixel?) units, the interaction switches from click to drag Behaviors/SingleClickAndDragBehavior.h  
ModifierCheckFunc TFunction< bool(const FInputDeviceState &)> WantsCapture() will only return capture request if this function returns true (or is null) Behaviors/SingleClickAndDragBehavior.h  
Modifiers FInputBehaviorModifierStates The modifier set for this behavior Behaviors/SingleClickAndDragBehavior.h  

Protected

Name Type Remarks Include Path Unreal Specifiers
bHasActiveCapture bool Set to true between BeginCapture and capture end (release/force-end). Behaviors/SingleClickAndDragBehavior.h  
bImmediatelyBeginDragInBeginCapture bool Flag used to communicate between WantsCapture and BeginCapture Behaviors/SingleClickAndDragBehavior.h  
bImmediatelyClickInBeginCapture bool Flag used to communicate between WantsCapture and BeginCapture Behaviors/SingleClickAndDragBehavior.h  
bIsBeyondDragDistance bool Updated to mark whether mouse movement has moved beyond drag distance Behaviors/SingleClickAndDragBehavior.h  
bIsDragging bool Set to true if we are in an active drag capture, eg after rejecting possible click Behaviors/SingleClickAndDragBehavior.h  
CaptureSide EInputCaptureSide Device capture Behaviors/SingleClickAndDragBehavior.h  
InitialMouseDownRay TOptional< FInputDeviceRay > The initial mouse down position. Behaviors/SingleClickAndDragBehavior.h  
PendingDragPriority TOptional< FInputCapturePriority > When set, the drag priority used when mouse motion has not yet moved byond the minimum drag distance. Behaviors/SingleClickAndDragBehavior.h  
Target ISingleClickAndDragBehaviorTarget * Click and Drag Target object. Behaviors/SingleClickAndDragBehavior.h  
UseUnboundedCursor TAttribute< bool >   Behaviors/SingleClickAndDragBehavior.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

void SetPendingDragPriority ( TOptional< FInputCapturePriority > InPriority
)

   Behaviors/SingleClickAndDragBehavior.h  

void SetUsesUnboundedCursor ( TAttribute< bool > InUsesUnboundedCursor
)

   Behaviors/SingleClickAndDragBehavior.h  

bool UsesUnboundedCursor()

   Behaviors/SingleClickAndDragBehavior.h  

Public Virtual

Name Remarks Include Path Unreal Specifiers

virtual void Initialize ( ISingleClickAndDragBehaviorTarget* InTarget
)

 Set the targets for Click and Drag interactions Behaviors/SingleClickAndDragBehavior.h  

Overridden from UAnyButtonInputBehavior

Name Remarks Include Path Unreal Specifiers

virtual FInputDeviceRay GetDeviceRay ( const FInputDeviceState& InInputDeviceState
)

   Behaviors/SingleClickAndDragBehavior.h  

Overridden from UInputBehavior

Name Remarks Include Path Unreal Specifiers

virtual FInputCaptureUpdate BeginCapture ( const FInputDeviceState& InInputState,
EInputCaptureSide InCaptureSide
)

   Behaviors/SingleClickAndDragBehavior.h  

virtual void ForceEndCapture ( const FInputCaptureData& InCaptureData
)

   Behaviors/SingleClickAndDragBehavior.h  

virtual FInputCapturePriority GetPriority()

   Behaviors/SingleClickAndDragBehavior.h  

virtual FInputCaptureUpdate UpdateCapture ( const FInputDeviceState& InInputState,
const FInputCaptureData& InCaptureData
)

   Behaviors/SingleClickAndDragBehavior.h  

virtual FInputCaptureRequest WantsCapture ( const FInputDeviceState& InInputState
)

   Behaviors/SingleClickAndDragBehavior.h  

Protected Virtual

Name Remarks Include Path Unreal Specifiers

virtual void OnClickDragInternal ( const FInputDeviceState& InInput,
const FInputCaptureData& InData
)

 Internal function that forwards click evens to Target::OnClickDrag, you can customize behavior here Behaviors/SingleClickAndDragBehavior.h  

virtual void OnClickPressInternal ( const FInputDeviceState& InInput,
EInputCaptureSide InSide
)

 Internal function that forwards click evens to Target::OnClickPress, you can customize behavior here Behaviors/SingleClickAndDragBehavior.h  

virtual void OnClickReleaseInternal ( const FInputDeviceState& InInput,
const FInputCaptureData& InData
)

 Internal function that forwards click evens to Target::OnClickRelease, you can customize behavior here Behaviors/SingleClickAndDragBehavior.h  

virtual void OnDragStartedInternal ( const FInputDeviceState& InInput,
const FInputCaptureData& InData
)

 Internal function that forwards click evens to Target::OnDragStarted, you can customize behavior here Behaviors/SingleClickAndDragBehavior.h  

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