Legacy Documentation: Version 5.5
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Dropdown

class in UnityEngine.UI

/

Inherits from:UI.Selectable


Implements interfaces:ICancelHandler, IDeselectHandler, IEventSystemHandler, IEventSystemHandler, IMoveHandler, IPointerClickHandler, IPointerDownHandler, IPointerEnterHandler, IPointerExitHandler, IPointerUpHandler, ISelectHandler, ISubmitHandler

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Description

A standard dropdown that presents a list of options when clicked, of which one can be chosen.

The dropdown component is a Selectable. When an option is chosen, the label and/or image of the control changes to show the chosen option.

When a dropdown event occurs a callback is sent to any registered listeners of onValueChanged.

Variables

captionImageThe Image component to hold the image of the currently selected option.
captionTextThe Text component to hold the text of the currently selected option.
itemImageThe Image component to hold the image of the item.
itemTextThe Text component to hold the text of the item.
onValueChangedA UnityEvent that is invoked when when a user has clicked one of the options in the dropdown list.
optionsThe list of possible options. A text string and an image can be specified for each option.
templateThe Rect Transform of the template for the dropdown list.
valueThe index of the currently selected option. 0 is the first option, 1 is the second, and so on.

Public Functions

AddOptionsAdd multiple options to the options of the Dropdown based on a list of OptionData objects.
ClearOptionsClear the list of options in the Dropdown.
HideHide the dropdown list.
OnCancelCalled by a BaseInputModule when a Cancel event occurs.
OnPointerClickHandling for when the dropdown is 'clicked'.
OnSubmitWhat to do when the event system sends a submit Event.
RefreshShownValueRefreshes the text and image (if available) of the currently selected option.If you have modified the list of options, you should call this method afterwards to ensure that the visual state of the dropdown corresponds to the updated options.
ShowShow the dropdown list.

Protected Functions

CreateBlockerOverride this method to implement a different way to obtain a blocker GameObject.
CreateDropdownListOverride this method to implement a different way to obtain a dropdown list GameObject.
CreateItemOverride this method to implement a different way to obtain an option item.
DestroyBlockerOverride this method to implement a different way to dispose of a blocker GameObject that blocks clicks to other controls while the dropdown list is open.
DestroyDropdownListOverride this method to implement a different way to dispose of a dropdown list GameObject.
DestroyItemOverride this method to implement a different way to dispose of an option item.

Inherited members

Static Variables

allSelectablesList of all the selectable objects currently active in the scene.

Variables

enabledEnabled Behaviours are Updated, disabled Behaviours are not.
isActiveAndEnabledHas the Behaviour had enabled called.
gameObjectThe game object this component is attached to. A component is always attached to a game object.
tagThe tag of this game object.
transformThe Transform attached to this GameObject.
runInEditModeAllow a specific instance of a MonoBehaviour to run in edit mode (only available in the editor).
useGUILayoutDisabling this lets you skip the GUI layout phase.
hideFlagsShould the object be hidden, saved with the scene or modifiable by the user?
nameThe name of the object.
animationTriggersThe AnimationTriggers for this selectable object.
animatorConvenience function to get the Animator component on the GameObject.
colorsThe ColorBlock for this selectable object.
imageConvenience function that converts the referenced Graphic to a Image, if possible.
interactableUI.Selectable.interactable.
navigationThe Navigation setting for this selectable object.
spriteStateThe SpriteState for this selectable object.
targetGraphicGraphic that will be transitioned upon.
transitionThe type of transition that will be applied to the targetGraphic when the state changes.

Public Functions

BroadcastMessageCalls the method named methodName on every MonoBehaviour in this game object or any of its children.
CompareTagIs this game object tagged with tag ?
GetComponentReturns the component of Type type if the game object has one attached, null if it doesn't.
GetComponentInChildrenReturns the component of Type type in the GameObject or any of its children using depth first search.
GetComponentInParentReturns the component of Type type in the GameObject or any of its parents.
GetComponentsReturns all components of Type type in the GameObject.
GetComponentsInChildrenReturns all components of Type type in the GameObject or any of its children.
GetComponentsInParentReturns all components of Type type in the GameObject or any of its parents.
SendMessageCalls the method named methodName on every MonoBehaviour in this game object.
SendMessageUpwardsCalls the method named methodName on every MonoBehaviour in this game object and on every ancestor of the behaviour.
CancelInvokeCancels all Invoke calls on this MonoBehaviour.
InvokeInvokes the method methodName in time seconds.
InvokeRepeatingInvokes the method methodName in time seconds, then repeatedly every repeatRate seconds.
IsInvokingIs any invoke on methodName pending?
StartCoroutineStarts a coroutine.
StopAllCoroutinesStops all coroutines running on this behaviour.
StopCoroutineStops the first coroutine named methodName, or the coroutine stored in routine running on this behaviour.
GetInstanceIDReturns the instance id of the object.
ToStringReturns the name of the game object.
FindSelectableFinds the selectable object next to this one.
FindSelectableOnDownFind the selectable object below this one.
FindSelectableOnLeftFind the selectable object to the left of this one.
FindSelectableOnRightFind the selectable object to the right of this one.
FindSelectableOnUpFind the selectable object above this one.
IsInteractableUI.Selectable.IsInteractable.
OnDeselectUnset selection and transition to appropriate state.
OnMoveDetermine in which of the 4 move directions the next selectable object should be found.
OnPointerDownEvaluate current state and transition to pressed state.
OnPointerEnterEvaluate current state and transition to appropriate state.
OnPointerExitEvaluate current state and transition to normal state.
OnPointerUpEvaluate eventData and transition to appropriate state.
OnSelectSet selection and transition to appropriate state.
SelectSelects this Selectable.
IsActiveReturns true if the GameObject and the Component are active.
IsDestroyedReturns true if the native representation of the behaviour has been destroyed.

Protected Functions

DoStateTransitionTransition the Selectable to the entered state.
InstantClearStateClear any internal state from the Selectable (used when disabling).
IsHighlightedIs the selectable currently 'highlighted'.
IsPressedWhether the current selectable is being pressed.
OnDisableSee MonoBehaviour.OnDisable.
UpdateSelectionStateInternally update the selection state of the Selectable.
AwakeSee MonoBehaviour.Awake.
OnBeforeTransformParentChangedSee MonoBehaviour.OnBeforeTransformParentChanged.
OnCanvasGroupChangedSee MonoBehaviour.OnCanvasGroupChanged.
OnCanvasHierarchyChangedCalled when the state of the parent Canvas is changed.
OnDestroySee MonoBehaviour.OnDestroy.
OnDidApplyAnimationPropertiesSee LayoutGroup.OnDidApplyAnimationProperties.
OnDisableSee MonoBehaviour.OnDisable.
OnEnableSee MonoBehaviour.OnEnable.
OnRectTransformDimensionsChangeThis callback is called if an associated RectTransform has its dimensions changed. The call is also made to all child rect transforms, even if the child transform itself doesn't change - as it could have, depending on its anchoring.
OnTransformParentChangedSee MonoBehaviour.OnRectTransformParentChanged.
OnValidateSee MonoBehaviour.OnValidate.
ResetSee MonoBehaviour.Reset.
StartSee MonoBehaviour.Start.

Static Functions

printLogs message to the Unity Console (identical to Debug.Log).
DestroyRemoves a gameobject, component or asset.
DestroyImmediateDestroys the object obj immediately.
DontDestroyOnLoadMakes the object target not be destroyed automatically when loading a new scene.
FindObjectOfTypeReturns the first active loaded object of Type type.
FindObjectsOfTypeReturns a list of all active loaded objects of Type type.
InstantiateClones the object original and returns the clone.

Operators

boolDoes the object exist?
operator !=Compares if two objects refer to a different object.
operator ==Compares two object references to see if they refer to the same object.

Messages

AwakeAwake is called when the script instance is being loaded.
FixedUpdateThis function is called every fixed framerate frame, if the MonoBehaviour is enabled.
LateUpdateLateUpdate is called every frame, if the Behaviour is enabled.
OnAnimatorIKCallback for setting up animation IK (inverse kinematics).
OnAnimatorMoveCallback for processing animation movements for modifying root motion.
OnApplicationFocusSent to all GameObjects when the player gets or loses focus.
OnApplicationPauseSent to all GameObjects when the application pauses.
OnApplicationQuitSent to all game objects before the application is quit.
OnAudioFilterReadIf OnAudioFilterRead is implemented, Unity will insert a custom filter into the audio DSP chain.
OnBecameInvisibleOnBecameInvisible is called when the renderer is no longer visible by any camera.
OnBecameVisibleOnBecameVisible is called when the renderer became visible by any camera.
OnCollisionEnterOnCollisionEnter is called when this collider/rigidbody has begun touching another rigidbody/collider.
OnCollisionEnter2DSent when an incoming collider makes contact with this object's collider (2D physics only).
OnCollisionExitOnCollisionExit is called when this collider/rigidbody has stopped touching another rigidbody/collider.
OnCollisionExit2DSent when a collider on another object stops touching this object's collider (2D physics only).
OnCollisionStayOnCollisionStay is called once per frame for every collider/rigidbody that is touching rigidbody/collider.
OnCollisionStay2DSent each frame where a collider on another object is touching this object's collider (2D physics only).
OnConnectedToServerCalled on the client when you have successfully connected to a server.
OnControllerColliderHitOnControllerColliderHit is called when the controller hits a collider while performing a Move.
OnDestroyThis function is called when the MonoBehaviour will be destroyed.
OnDisableThis function is called when the behaviour becomes disabled () or inactive.
OnDisconnectedFromServerCalled on the client when the connection was lost or you disconnected from the server.
OnDrawGizmosImplement OnDrawGizmos if you want to draw gizmos that are also pickable and always drawn.
OnDrawGizmosSelectedImplement OnDrawGizmosSelected to draw a gizmo if the object is selected.
OnEnableThis function is called when the object becomes enabled and active.
OnFailedToConnectCalled on the client when a connection attempt fails for some reason.
OnFailedToConnectToMasterServerCalled on clients or servers when there is a problem connecting to the MasterServer.
OnGUIOnGUI is called for rendering and handling GUI events.
OnJointBreakCalled when a joint attached to the same game object broke.
OnJointBreak2DCalled when a Joint2D attached to the same game object breaks.
OnMasterServerEventCalled on clients or servers when reporting events from the MasterServer.
OnMouseDownOnMouseDown is called when the user has pressed the mouse button while over the GUIElement or Collider.
OnMouseDragOnMouseDrag is called when the user has clicked on a GUIElement or Collider and is still holding down the mouse.
OnMouseEnterCalled when the mouse enters the GUIElement or Collider.
OnMouseExitCalled when the mouse is not any longer over the GUIElement or Collider.
OnMouseOverCalled every frame while the mouse is over the GUIElement or Collider.
OnMouseUpOnMouseUp is called when the user has released the mouse button.
OnMouseUpAsButtonOnMouseUpAsButton is only called when the mouse is released over the same GUIElement or Collider as it was pressed.
OnNetworkInstantiateCalled on objects which have been network instantiated with Network.Instantiate.
OnParticleCollisionOnParticleCollision is called when a particle hits a Collider.
OnParticleTriggerOnParticleTrigger is called when any particles in a particle system meet the conditions in the trigger module.
OnPlayerConnectedCalled on the server whenever a new player has successfully connected.
OnPlayerDisconnectedCalled on the server whenever a player disconnected from the server.
OnPostRenderOnPostRender is called after a camera finished rendering the scene.
OnPreCullOnPreCull is called before a camera culls the scene.
OnPreRenderOnPreRender is called before a camera starts rendering the scene.
OnRenderImageOnRenderImage is called after all rendering is complete to render image.
OnRenderObjectOnRenderObject is called after camera has rendered the scene.
OnSerializeNetworkViewUsed to customize synchronization of variables in a script watched by a network view.
OnServerInitializedCalled on the server whenever a Network.InitializeServer was invoked and has completed.
OnTransformChildrenChangedThis function is called when the list of children of the transform of the GameObject has changed.
OnTransformParentChangedThis function is called when the parent property of the transform of the GameObject has changed.
OnTriggerEnterOnTriggerEnter is called when the Collider other enters the trigger.
OnTriggerEnter2DSent when another object enters a trigger collider attached to this object (2D physics only).
OnTriggerExitOnTriggerExit is called when the Collider other has stopped touching the trigger.
OnTriggerExit2DSent when another object leaves a trigger collider attached to this object (2D physics only).
OnTriggerStayOnTriggerStay is called once per frame for every Collider other that is touching the trigger.
OnTriggerStay2DSent each frame where another object is within a trigger collider attached to this object (2D physics only).
OnValidateThis function is called when the script is loaded or a value is changed in the inspector (Called in the editor only).
OnWillRenderObjectOnWillRenderObject is called for each camera if the object is visible.
ResetReset to default values.
StartStart is called on the frame when a script is enabled just before any of the Update methods is called the first time.
UpdateUpdate is called every frame, if the MonoBehaviour is enabled.
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