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Class

UIDragDetector

Inherits
UIComponent › UIBase › Instance › Object
Memory category
Instances

Instance which facilitates and encourages interaction with UI elements in an experience.

The UIDragDetector instance facilitates and encourages interaction with 2D user interface elements in an experience, such as sliders and spinners. Key features include:

  • Place a UIDragDetector under any GuiObject instance to make it draggable via all inputs without a single line of code.

  • Choose from several DragStyle options, define how the object responds to motion via ResponseStyle, and optionally apply axis, movement limits, or drag boundaries.

  • Scripts can respond to manipulation of dragged objects to drive logic responses, such as adjusting settings.

  • UIDragDetectors work in Studio as long as you're not using the Select, Move, Scale, or Rotate tools, nor certain plugins or Studio's UI editor tools.

Properties 22#

ActivatedCursorIconContentIdSets the cursor icon to display when the mouse is activated over the parent of this UIDragDetector.ReadSafe
ActivatedCursorIconContentContentSets the cursor icon to display when the mouse is activated over the parent of this UIDragDetector. Only supports asset URIsReadSafe
BoundingBehaviorUIDragDetectorBoundingBehaviorDetermines bounding behavior of the dragged UI object when the detector's BoundingUI is set.ReadSafe
BoundingUIGuiBase2dInstance whose bounding area defines the drag boundaries for the parent GuiObject.ReadSafe
CursorIconContentIdSets the cursor icon to display when the mouse is hovered over the parent of this UIDragDetector.ReadSafe
CursorIconContentContentSets the cursor icon to display when the mouse is hovered over the parent of this UIDragDetector. Only asset URIs are supported.ReadSafe
DragAxisVector2The drag axis for the UIDragDetector instance when DragStyle is set to UIDragDetectorDragStyle.TranslateLine.ReadSafe
DragRelativityUIDragDetectorDragRelativitySets the paradigm which defines the relativity of inputs/outputs from a custom drag function.ReadSafe
DragRotationfloatThe rotation performed by the current drag.ReadSafe
DragSpaceUIDragDetectorDragSpaceSets the paradigm which defines the space of inputs/outputs from a custom drag function.ReadSafe
DragStyleUIDragDetectorDragStyleThe paradigm used to generate proposed motion.ReadSafe
DragUDim2UDim2The translation performed by the current drag expressed in a UDim2 value.ReadSafe
EnabledbooleanWhether the UIDragDetector responds to user input.ReadSafe
MaxDragAnglefloatAlong with MinDragAngle, impedes the detector's attempts to generate rotational motion.ReadSafe
MaxDragTranslationUDim2Along with MinDragTranslation, impedes the detector's attempts to generate linear/planar motion.ReadSafe
MinDragAnglefloatAlong with MaxDragAngle, impedes the detector's attempts to generate rotational motion.ReadSafe
MinDragTranslationUDim2Along with MaxDragTranslation, impedes the detector's attempts to generate linear/planar motion.ReadSafe
ReferenceUIInstanceGuiObjectA GuiObject instance whose local space and absolute center position is the reference space and origin for the detector.ReadSafe
ResponseStyleUIDragDetectorResponseStyleThe paradigm used to define the response to proposed motion.ReadSafe
SelectionModeDragSpeedUDim2Maximum drag speed for translation.ReadSafe
SelectionModeRotateSpeedfloatMaximum angle per second the UIDragDetector can rotate at.ReadSafe
UIDragSpeedAxisMappingUIDragSpeedAxisMappingUIDragSpeedAxisMapping value that determines the X/Y dimension dragging speeds.ReadSafe

ActivatedCursorIcon: ContentId#

ReadSafe

Sets the cursor icon to display when the mouse is activated over the parent of this UIDragDetector. If this property is left blank, the detector will use the default icon.

To change the activated cursor icon, set this property to the asset ID of the image you'd like to use.

ActivatedCursorIconContent: Content#

ReadSafe

Sets the cursor icon to display when the mouse is activated over the parent of this UIDragDetector. If this property is left blank, the detector will use the default icon.

To change the activated cursor icon, set this property to the asset ID of the image you'd like to use. Only asset URIs are supported for this property.

BoundingBehavior: UIDragDetectorBoundingBehavior#

ReadSafe

Determines bounding behavior of the dragged UI object when the detector's BoundingUI is set. See UIDragDetectorBoundingBehavior for details on each setting's behavior.

BoundingUI: GuiBase2d#

ReadSafe

When set, the UIDragDetector instance will not allow the bounds of the parent GuiObject to be dragged outside the bounds of the BoundingUI instance.

Note that if a portion of the parent GuiObject is outside the BoundingUI bounds, the initial input position at drag start and its relative position during drag will be used for bounding detection until the entirety of the dragged object is within the bounds, after which the object will be constrained inside the bounds.

CursorIcon: ContentId#

ReadSafe

Sets the cursor icon to display when the mouse is hovered over the parent of this UIDragDetector. If this property is left blank, the detector will use the default icon.

To change the cursor icon, set this property to the asset ID of the image you'd like to use.

CursorIconContent: Content#

ReadSafe

Sets the cursor icon to display when the mouse is hovered over the parent of this UIDragDetector. If this property is left blank, the detector will use the default icon.

To change the cursor icon, set this property to the asset ID of the image you'd like to use. Only asset URIs are supported for this property.

DragAxis: Vector2#

ReadSafe

Vector2 value that defines the axis of movement for the dragged object when DragStyle is set to UIDragDetectorDragStyle.TranslateLine. The axis is defined in the local space of the UIDragDetector unless ReferenceUIInstance is defined, in which case the axis is defined in that instance's local space.

DragRelativity: UIDragDetectorDragRelativity#

ReadSafe

Only applies if a custom drag function is registered through SetDragStyleFunction() or AddConstraintFunction(). Sets the paradigm which defines the relativity of the registered function's inputs/outputs.

For example, returning a Datatype.UDim2.fromOffset(1, 0) from a registered function with this property set to UIDragDetectorDragRelativity.Absolute will move the detector's parent to (1, 0) in the designated DragSpace, while returning the same UDim2 with this property set to UIDragDetectorDragRelativity.Relative will move the detector's parent by (1, 0) in the designated DragSpace.

DragRotation: float#

ReadSafe

The rotation performed by the current drag. This value is defined in degrees relative to the local space of the UIDragDetector unless ReferenceUIInstance is defined, in which case the rotation is defined in the local space of that instance and from its positive X axis.

This property can be changed while there is no active drag to rotate the dragged object.

DragSpace: UIDragDetectorDragSpace#

ReadSafe

Only applies if a custom drag function is registered through SetDragStyleFunction() or AddConstraintFunction(). Sets the paradigm which defines the space of the registered function's inputs/outputs.

For example, if the detector's parent GuiObject is a child of a parent GuiObject that's rotated:

DragStyle: UIDragDetectorDragStyle#

ReadSafe

The paradigm used to generate proposed motion, given a stream of input position vectors. See UIDragDetectorDragStyle for options.

DragUDim2: UDim2#

ReadSafe

The translation performed by the current drag expressed in a UDim2 value. Translation is done through Offset or Scale value changes depending on the DragRelativity value, and it is relative to the detector's local space unless a ReferenceUIInstance is defined.

This property can be changed while there is no active drag to move the dragged object.

Enabled: boolean#

ReadSafe

If true, the UIDragDetector responds to user input; if false, it does not.

MaxDragAngle: float#

ReadSafe

If this property is greater than MinDragAngle, rotation will be clamped within the range of MinDragAngle and MaxDragAngle. Positive values impede clockwise rotation while negative values impede counterclockwise rotation.

This is not a constraint; it merely impedes the detector's attempts to generate motion in order to remain within limits. See AddConstraintFunction() to add custom constraint to a drag.

Only relevant if DragStyle is UIDragDetectorDragStyle.Rotate.

MaxDragTranslation: UDim2#

ReadSafe

If the corresponding Offset and/or Scale values are greater than those of MinDragTranslation in all dimensions, linear/planar translation will be clamped within the range of MinDragTranslation and MaxDragTranslation.

This is not a constraint; it merely impedes the detector's attempts to generate motion in order to remain within limits. See AddConstraintFunction() to add custom constraint to a drag.

Only relevant if DragStyle is UIDragDetectorDragStyle.TranslateLine or UIDragDetectorDragStyle.TranslatePlane.

MinDragAngle: float#

ReadSafe

If this property is less than MaxDragAngle, rotation will be clamped within the range of MinDragAngle and MaxDragAngle. Positive values impede clockwise rotation while negative values impede counterclockwise rotation.

This is not a constraint; it merely impedes the detector's attempts to generate motion in order to remain within limits. See AddConstraintFunction() to add custom constraint to a drag.

Only relevant if DragStyle is UIDragDetectorDragStyle.Rotate.

MinDragTranslation: UDim2#

ReadSafe

If the corresponding Offset and/or Scale values are less than those of MaxDragTranslation in all dimensions, linear/planar translation will be clamped within the range of MinDragTranslation and MaxDragTranslation.

This is not a constraint; it merely impedes the detector's attempts to generate motion in order to remain within limits. See AddConstraintFunction() to add custom constraint to a drag.

Only relevant if DragStyle is UIDragDetectorDragStyle.TranslateLine or UIDragDetectorDragStyle.TranslatePlane.

ReferenceUIInstance: GuiObject#

ReadSafe

A GuiObject instance whose local space and absolute center position is the reference space and origin for the detector. Setting this reference affects properties such as DragUDim2, DragRotation, and the behavior of DragAxis.

ResponseStyle: UIDragDetectorResponseStyle#

ReadSafe

Once the proposed motion has been computed and potentially constrained, this paradigm is used to deterimine how to move (or not move) the GuiObject affected by the UIDragDetector. See UIDragDetectorResponseStyle for options.

SelectionModeDragSpeed: UDim2#

ReadSafe

Defines the maximum drag speed for translation as a combination of Scale and Offset of the first ancestor ScreenGui or SurfaceGui the UIDragDetector belongs to. This value must be positive and any value below 0 will be clamped to 0.

SelectionModeRotateSpeed: float#

ReadSafe

Defines the maximum angle per second at which the UIDragDetector can rotate. This value must be positive and any value below 0 will be clamped to 0.

UIDragSpeedAxisMapping: UIDragSpeedAxisMapping#

ReadSafe

UIDragSpeedAxisMapping value that determines the X/Y dimension dragging speeds.

Methods 4#

AddConstraintFunctionAdds a function to modify or constrain proposed motion.
GetReferencePositionReturns the reference UDim2 position of the current drag's reference origin.
GetReferenceRotationReturns the reference rotation of the current drag's reference element.
SetDragStyleFunctionPasses a function to be used if and only if DragStyle is set to UIDragDetectorDragStyle.Scriptable.

AddConstraintFunction(priority: int, function: Function): RBXScriptConnection#

Adds a function to modify or constrain proposed motion. The function takes an input UDim2 (position) and float (rotation) of proposed motion and returns a UDim2 and float of modified or unmodified motion. You can add multiple functions which will be called in order by priority, passing the results along in a chain.

The input is expressed in the space defined by the DragSpace property, either as a delta or the final desired position/rotation based on the DragRelativity property. The output should be expressed in the same space and relativity, unless overridden by returning a specified UIDragDetectorDragRelativity and UIDragDetectorDragSpace as the third and fourth return values.

To remove an added constraint function, call Disconnect() on the returned connection object.

NameTypeDefaultDescription
priorityintThe order of priority for functions added via this method. Higher values take precedence over lower values.
functionFunctionFunction for modifying or constraining proposed motion. This function takes in input UDim2 and float of proposed motion and returns a UDim2 and float of modified or unmodified motion. It can optionally return an UIDragDetectorDragRelativity and UIDragDetectorDragSpace as the third and fourth return values as output overrides.
Returns

GetReferencePosition(): UDim2#

When no ReferenceUIInstance is set, this function returns the UDim2 position of the dragged object's immediate parent GuiObject (if one exists), or else the UDim2 position of the dragged object.

When a ReferenceUIInstance is set, this function returns the UDim2 position of that reference instance.

Returns
  • UDim2 — UDim2 position of the current drag's reference element.

GetReferenceRotation(): float#

When no ReferenceUIInstance is set, this function returns the rotation of the dragged object's immediate parent GuiObject (if one exists), or else the rotation of the dragged object.

When a ReferenceUIInstance is set, this function returns the rotation of that reference instance.

Returns
  • float — Rotation of the current drag's reference element.

SetDragStyleFunction(function: Function): ()#

Passes a function to be used if and only if DragStyle is set to UIDragDetectorDragStyle.Scriptable. The given function receives the signal's screen space input position with type Vector2, and it returns a UDim2 (position) and float (rotation) containing the desired motion of the drag. The space of the return values and the relativity of the motion are determined by the DragSpace and DragRelativity properties, unless overridden by returning a specified UIDragDetectorDragRelativity and UIDragDetectorDragSpace as the third and fourth return values.

If the function returns nil, the object will not be moved. This is useful if the script has not yet collected all the information it needs to give the correct answer, or in temporary cases where you want the object to stay where it is.

NameTypeDefaultDescription
functionFunctionFunction for monitoring DragContinue signals. This function receives the signal's screen space input position and returns a UDim2 and float containing the desired motion of the drag in the desired space and relativity. If this function returns nil, the object will not be moved.
Returns
  • ()

Events 3#

DragContinueFires when a user continues dragging the UI element after DragStart has been initiated.
DragEndFires when a user stops dragging the UI element.
DragStartFires when a user starts dragging the UI element.

DragContinue(inputPosition: Vector2)#

Fires when a user continues dragging the UI element after DragStart has been initiated.

NameTypeDefaultDescription
inputPositionVector2Vector2 representing the current input position.

DragEnd(inputPosition: Vector2)#

Fires when a user stops dragging the UI element.

NameTypeDefaultDescription
inputPositionVector2Vector2 representing the current input position.

DragStart(inputPosition: Vector2)#

Fires when a user starts dragging the UI element.

NameTypeDefaultDescription
inputPositionVector2Vector2 representing the current input position.

Inherited members#

Inherited from Instance 58
Inherited from Object 6
Properties (2)

ClassName, className

Events (1)

Changed