Callbacks are scripting "hooks" that the engine provides, which allow you to write custom responses to events. Callbacks are optional, if the engine fires off a callback and nothing is defined for that event, then nothing happens.

A common callback that is used in many types of games is "onCollision". When the physics system registers a contact between two objects that have their collision properties properly defined and at least one of the objects has its callback turned on, you can define a script reponse for this event like so:

function SceneObject::onCollision(%this, %sceneObject, %collisionDetails)
{
}

Depending on the namespace and what the object inherits from, you can define callbacks at the name, class/superclass, behavior, or object level.

Remember that the amount of callbacks available to an object depends on its inheritance tree. A Sprite, for example, is not listed here but has the callbacks available from SpriteBase, SceneObject, and SimObject.

SimObject

• onAdd
• onRemove

CompositeSprite

• onCustomLayout

ParticlePlayer

• onStopParticlePlayer

SceneObject

• onUpdate
• onWake
• onSleep
• onMoveToComplete
• onRotateToComplete
• onFadeToComplete
• onGrowToComplete

Trigger

• onEnter
• onStay
• onLeave

SpriteBase

• onAnimationEnd

Scene

• onSceneCollision
• onCollision
• onSceneEndCollision
• onEndCollision
• onSceneUpdate
• onSceneRender
• onAddToScene
• onRemoveFromScene
• onSafeDelete

BehaviorComponent

• onBehaviorAdd
• onBehaviorRemove
• onBehaviorMissing

SimComponent

• onComponentAdd
• onComponentRemove

SceneWindow

• onExtentChange

GuiButtonBaseCtrl

• onMouseEnter
• onMouseLeave
• onMouseUp
• onRightClick
• onClick

GuiCheckBoxCtrl

• onClick

GuiSceneObjectCtrl

• onDoubleClick
• onMouseEnter
• onMouseLeave
• onMouseDragged

GuiAutoScrollCtrl

• onTick

GuiFormCtrl

• onResize

GuiRolloutCtrl

• onCollapsed
• onExpanded

GuiScrollCtrl

• onScroll

GuiTabBookCtrl

• onTabSelected

GuiDebugger

• DbgSetCursorWatch
• onRemoveBreakPoint
• onSetBreakPoint
• onSetWatch

GuiEditCtrl

• onClearSelected
• onAddSelected
• onAddNewCtrl
• onPreEdit
• onPostEdit
• onSelect
• onSelectionParentChange
• onPreSelectionNudged
• onPostDelectionNudged
• onSelectionMoved
• onTrashSelection
• onAddNewCtrlSet
• onDelete
• onControlInspectPreApply
• onControlInspectPostApply

GuiMenuBar

• onMouseInMenu
• onMenuSelect
• onMenuItemSelect
• onSubmenuSelect

GuiArrayCtrl

• onSelect
• onRightMouseDown

GuiCanvas

• onWake

GuiColorPicker

• onMouseDown
• onMouseDragged
• onMouseMove
• onMouseEnter
• onMouseLeave
• onMouseUp

GuiControl

• onWake
• onSleep
• onAction
• onDialogPush
• onDialogPop

GuiInputCtrl

• onInputEvent

GuiListBoxCtrl

• onUnSelect
• onSelect
• onMouseDragged
• onDoubleClick

GuiMessageVectorCtrl

• urlClickCallback

GuiMLTextCtrl

• onResize
• onURL

GuiPopUpCtrl

• onSelect
• onCancel

GuiPopUpCtrlEx

• onSelect
• onHotTrackItem
• onCancel

GuiScriptNotifyCtrl

• onChildAdded
• onChildRemoved
• onResize
• onChildResized
• onParentResized
• onLoseFirstResponder
• onGainFirstResponder

GuiSliderCtrl

• onMouseDragged

GuiTextEditCtrl

• onMouseDown
• onMouseDragged
• onMouseUp
• onTabComplete
• onValidate
• onReturn
• onLoseFirstResponder

GuiTextListCtrl

• onSelect
• onDeleteKey

GuiTreeViewCtrl

• onDeleteObject
• onWake
• onDefineIcons
• onInstantGroupSelected
• onRemoveSelection
• onAddSelection
• onInspect
• onUnSelect
• onDeleteSelection
• onObjectDeleteCompleted
• onKeyDown
• onClearSelection
• onRightMouseDown

ModuleManager

• onModuleRegister
• onModulePreLoad
• onModulePostLoad
• onModulePreUnload
• onModulePostUnload

PopupMenu

• onMessageReceived

GameCenter

• onAdd
• onRemove
• gameCenterAuthenticationChanged

iOSPlatform

• onExecuteDone

iOSStream

• oniOSStreamEnd

main

• oniOSResignActive
• oniOSBecomeActive
• oniOSWillTerminate
• onExit
• oniOSOrientationToLandscapeLeft
• oniOSOrientationToLandscapeRight
• oniOSOrientationToPortrait
• oniOSOrientationToPortraitUpsideDown

WinWindow

• onDropBegin
• onDropFile
• onDropEnd
• onClosePressed
• onWindowFocusChange

GameConnection

• onConnectionTimeout
• onConnectionAccepted
• onConnectRequestTimedOut
• onConnectionDropped
• onConnectRequestRejected
• onConnectionError
• onDrop
• setLagIcon

NetDownload

• onFileChunkReceived

NetGhost

• onGhostAlwaysObjectReceived
• onGhostAlwaysStarted

ServerQuery

• onServerQueryStatus
• onClearGameTypes
• onAddGameType
• onClearMissionTypes
• onAddMissionType

TcpObject

• onConnectRequest
• onLine
• onDNSResolved
• onDNSFailed
• onConnected
• onConnectFailed
• onDisconnect

UndoManager

• onClear
• onRemoveUndo
• onUndo
• onRedo
• onAddUndo

ScriptMsgListener

• onMessageReceived
• onMessageObjectReceived
• onAddToQueue
• onRemoveFromQueue