val dataModel = EntityContext.getDataModel()
// setup button event listener
button.entity.registerEventListener<EventArgs>("button") { _, _ ->
  // handle event
}
dataModel?.sendEvent(entity, "button", EventArgs("click", dataModel))

Also see PhysicsSample⁠ sample project for a more in depth example of registering custom event listeners.

Signature

class DataModel(dataModel_: Long)

Constructors

DataModel ( dataModel_ )

Signature

constructor(dataModel_: Long)

Parameters

dataModel_: Long

Returns

DataModel

Methods

bumpComponentVersion ( entityId , componentId )	Bumps the component version, marking it as "changed" without modifying data. This forces a component to be considered changed for change detection purposes, even when the actual component data hasn't been modified. This will trigger component change listeners and queries that look for changed components. Signature fun bumpComponentVersion(entityId: Long, componentId: Int) Parameters `entityId: Long` The ID of the entity. `componentId: Int` The ID of the component to mark as changed.
createEntity ()	Creates a new entity in the data model. Signature fun createEntity(): Entity Returns `Entity` The Entity.
createEntity ( components )	Creates a new entity in the data model with components. Signature fun createEntity(components: List<ComponentBase>): Entity Parameters `components: List` Returns `Entity` The Entity.
createEntity ( components )	Creates a new entity in the data model with components. Signature fun createEntity(vararg components: ComponentBase): Entity Parameters `components: ComponentBase` Returns `Entity` The Entity.
createFilterHandle ( filterCode , filterIntCode , filterLongCode , filterFloatCode , filterStringCode )	Creates a pre-compiled filter handle for efficient reuse in CachedQuery. The filter handle compiles the filter bytecode into a std::function once, avoiding the overhead of rebuilding the filter on every query evaluation. The handle is owned by the caller and must be destroyed with DataModel.Companion.destroyFilterHandle when no longer needed. Signature fun createFilterHandle(filterCode: IntArray?, filterIntCode: IntArray?, filterLongCode: LongArray?, filterFloatCode: FloatArray?, filterStringCode: Array<String>?): Long Parameters `filterCode: IntArray?` The filter bytecode. `filterIntCode: IntArray?` Integer values used in the filter. `filterLongCode: LongArray?` Long values used in the filter. `filterFloatCode: FloatArray?` Float values used in the filter. `filterStringCode: Array?` String values used in the filter. Returns `Long` A handle (as Long pointer), or 0L if no filter code was provided.
deleteEntity ( eid )	Deletes an entity from the data model. The entity will be included in deleted queries next tick. We recommend using Entity.destroy() instead of this function. Signature fun deleteEntity(eid: Long) Parameters `eid: Long` The ID of the entity to delete.
getAttributeReadCount ()	Returns the total number of attribute reads since the last counter reset. Signature fun getAttributeReadCount(): Int Returns `Int`
getAttributeReadSkipCount ()	Returns the number of attribute reads skipped (cache hit) since the last counter reset. Signature fun getAttributeReadSkipCount(): Int Returns `Int`
getAttributeReadVersionSkipCount ()	Returns the number of attribute reads skipped by version comparison since the last counter reset. Signature fun getAttributeReadVersionSkipCount(): Int Returns `Int`
getAttributeWriteCount ()	Returns the total number of attribute writes since the last counter reset. Signature fun getAttributeWriteCount(): Int Returns `Int`
getAttributeWriteSkipCount ()	Returns the number of attribute writes skipped by version match since the last counter reset. Signature fun getAttributeWriteSkipCount(): Int Returns `Int`
getAttributeWriteVersionSkipCount ()	Returns the number of attribute writes skipped by version comparison since the last counter reset. Signature fun getAttributeWriteVersionSkipCount(): Int Returns `Int`
getChangedEntitiesSinceWithFilterAndRemoval ( sinceVersion , componentIds , filterHandle )	Get all entity IDs that have changed since a given version using a pre-compiled filter handle. Returns packed array: matchingCount, ...matchingIds, ...removedIds Signature fun getChangedEntitiesSinceWithFilterAndRemoval(sinceVersion: ULong, componentIds: IntArray, filterHandle: Long): LongArray? Parameters `sinceVersion: ULong` The version to check against (exclusive - returns changes after this version). `componentIds: IntArray` Array of component/attribute IDs to check for. `filterHandle: Long` The pre-compiled filter handle from DataModel.createFilterHandle, or 0L for no filter. Returns `LongArray?` Packed array as described above, or null if no changes.
getChangedEntitiesSinceWithRemoval ( sinceVersion , componentIds )	Get all entity IDs that have changed since a given version, packed as: matchingCount, ...matchingIds, ...removedIds Where: matchingCount: number of entities that have ALL specified components matchingIds: entity IDs that match (indices 1 to matchingCount) removedIds: entity IDs that no longer match (indices matchingCount+1 to end) This is used by CachedQuery for incremental updates with component removal support. Signature fun getChangedEntitiesSinceWithRemoval(sinceVersion: ULong, componentIds: IntArray): LongArray? Parameters `sinceVersion: ULong` The version to check against (exclusive - returns changes after this version). `componentIds: IntArray` Array of component/attribute IDs to check for. Returns `LongArray?` Packed array as described above, or null if no changes.
getComponentIdsForEntity ( entityId , componentManager )	Gets all component IDs associated with a given entity. This function iterates through all registered component IDs (where componentId == attrId in attributeInfoMap) and checks if the entity has data for each component using a single batch JNI call to minimize JNI boundary crossings. Signature fun getComponentIdsForEntity(entityId: Long, componentManager: ComponentManager): IntArray Parameters `entityId: Long` The entity ID to query components for. `componentManager: ComponentManager` The ComponentManager containing the attributeInfoMap. Returns `IntArray` An IntArray of component IDs that the entity has.
getEventListenerForEvent ( eventType )	Gets all listeners registered for a specific event type. Parameters `eventType: String` The type of event to get listeners for. Returns `Set` A set of entity-listener pairs for the specified event type.
getKeyValueMap ( id , attribute )	Signature inline fun <T, V> getKeyValueMap(id: Long, attribute: Int): HashMap<T, V> Parameters `id: Long` `attribute: Int` Returns `HashMap`
getLastUpdateVersion ()	Experimental API. This gets a long that represents the last updated version of the data model. This is important for making updates the same tick as other component changes. Example: class MyComponentSystem() : SystemBase() { private var lastUpdateVersion = 0UL @OptIn(SpatialSDKExperimentalAPI::class) override fun execute() { for (entity in Query.where { changedSince(MyComponent.id, lastUpdateVersion) }.eval()) { // handle changing entity } lastUpdateVersion = EntityContext.getDataModel()!!.getLastUpdateVersion() } } Signature fun getLastUpdateVersion(): ULong Returns `ULong`
hasAllKeys ( id , componentIds )	Batch check if an entity has all specified component attributes. This is more efficient than calling hasKey() multiple times as it reduces JNI overhead. Signature fun hasAllKeys(id: Long, componentIds: IntArray): Boolean Parameters `id: Long` The ID of the entity. `componentIds: IntArray` Array of component/attribute IDs to check for. Returns `Boolean` True if the entity has all specified components, false otherwise.
hasKey ( id , attribute )	Checks if an entity has a specific attribute. Signature fun hasKey(id: Long, attribute: Int): Boolean Parameters `id: Long` The ID of the entity. `attribute: Int` The attribute ID to check for. Returns `Boolean` True if the entity has the attribute, false otherwise.
nativeGetKeyValueMap ( dataModel , id , attribute )	Signature external fun nativeGetKeyValueMap(dataModel: Long, id: Long, attribute: Int): Array<Any> Parameters `dataModel: Long` `id: Long` `attribute: Int` Returns `Array`
registerAttributeListener ( attribute , listener )	Registers a listener for changes to a specific attribute. Signature fun registerAttributeListener(attribute: Int, listener: AttributeListener) Parameters `attribute: Int` The ID of the attribute to listen for changes on. `listener: AttributeListener` The callback to invoke when the attribute changes.
registerComponentListener ( componentID , componentClass , listener )	Registers a listener for changes to a specific component. Signature fun registerComponentListener(componentID: Int, componentClass: KClass<*>, listener: ComponentListener) Parameters `componentID: Int` The ID of the component to listen for changes on. `componentClass: KClass` The class of the component. `listener: ComponentListener` The callback to invoke when the component changes.
registerDeleteListener ( listener )	Registers a listener to be notified when any entity is deleted. The listener is held via a weak reference, allowing the owning object (e.g., CachedQuery) to be garbage collected even without explicitly calling DataModel.removeDeleteListener. Stale references are automatically cleaned up during delete notifications. For proper cleanup semantics, callers should retain a strong reference to the returned DeleteListenerHolder for as long as they want to receive notifications. Signature fun registerDeleteListener(listener: (Long) -> Unit): DeleteListenerHolder Parameters `listener: Function1` The callback to invoke with the entity ID when an entity is deleted. Returns `DeleteListenerHolder` A DeleteListenerHolder that the caller should retain. When this holder is garbage collected, the listener will automatically stop receiving notifications.
registerEventListener ( entity , eventType , listener )	Registers a listener for events on a specific entity. Signature fun registerEventListener(entity: Entity, eventType: String, listener: EventListener<EventArgs>) Parameters `entity: Entity` The entity to listen for events on. `eventType: String` The type of event to listen for. `listener: EventListener` The callback to invoke when the event occurs.
registerLinkedEntityAttribute ( attributeID )	This method is experimental and is subject to change in the future. Registering a linked entity attribute makes it so that the DataModel will build a hierarchy based on the given entity attribute. This means that you can query for children of a given entity based on the registered linked entity attribute. Example: In Your Activity's OnCreate: EntityContext.getDataModel()?.registerLinkedEntityAttribute(MyComponent.myEntityAttributeData) Then you can query for children of a certain entity (Where their MyComponent.myEntityAttribute is myEntity) in a System Query: val query = Query.where { childrenOf(myEntity, MyComponent.myEntityAttributeData) } Signature fun registerLinkedEntityAttribute(attributeID: Int) Parameters `attributeID: Int`
removeComponentListener ( componentID )	Removes a previously registered component listener. Signature fun removeComponentListener(componentID: Int) Parameters `componentID: Int` The ID of the component to stop listening for changes on.
removeDeleteListener ( holder )	Removes a previously registered delete listener. Note: With weak reference semantics, explicit removal is optional. If the DeleteListenerHolder goes out of scope, the listener will automatically stop receiving notifications and be cleaned up during the next delete event. Signature fun removeDeleteListener(holder: DeleteListenerHolder) Parameters `holder: DeleteListenerHolder` The holder returned from DataModel.registerDeleteListener.
resetAttributeCounters ()	Resets all attribute counters to zero. Signature fun resetAttributeCounters()
willBeDeleted ( eid )	Checks if an entity will be deleted in the next frame. Returns true if deleteEntity() has been called on this entity in the current frame, but the entity hasn't been fully removed yet. The entity will be inaccessible starting in the next frame. Signature fun willBeDeleted(eid: Long): Boolean Parameters `eid: Long` The ID of the entity to check. Returns `Boolean` True if the entity is scheduled for deletion, false otherwise.

Companion Object

Methods

destroyFilterHandle ( filterHandle )	Destroys a filter handle created by DataModel.createFilterHandle. This is a static method that doesn't require a DataModel instance, allowing filter handles to be cleaned up even if the DataModel has been destroyed. Signature fun destroyFilterHandle(filterHandle: Long) Parameters `filterHandle: Long` The handle to destroy.
getLocalDataModelTime ()	Gets the local time based on the data model. Signature fun getLocalDataModelTime(): Long Returns `Long`