EntityCollection

new EntityCollection()

An observable collection of Entity instances where each entity has a unique id.

Members

readonlycollectionChanged :Event

Gets the event that is fired when entities are added or removed from the collection. The generated event is a EntityCollection.collectionChangedEventCallback.

readonlyentities :Array.<Entity>

Gets the array of Entity instances in the collection. This array should not be modified directly.

readonlyid :String

Gets a globally unique identifier for this collection.

Methods

staticEntityCollection.collectionChangedEventCallback(collection, added, removed, changed)

The signature of the event generated by EntityCollection#collectionChanged.
Name Type Description
collection EntityCollection The collection that triggered the event.
added Array.<Entity> The array of Entity instances that have been added to the collection.
removed Array.<Entity> The array of Entity instances that have been removed from the collection.
changed Array.<Entity> The array of Entity instances that have been modified.

add(entity)

Add an entity to the collection.
Name Type Description
entity Entity The entity to be added.
Throws:

computeAvailability()TimeInterval

Computes the maximum availability of the entities in the collection. If the collection contains a mix of infinitely available data and non-infinite data, it will return the interval pertaining to the non-infinite data only. If all data is infinite, an infinite interval will be returned.
Returns:
The availability of entities in the collection.

getById(id)Entity

Gets an entity with the specified id.
Name Type Description
id Object The id of the entity to retrieve.
Returns:
The entity with the provided id or undefined if the id did not exist in the collection.

getOrCreateEntity(id)Entity

Gets an entity with the specified id or creates it and adds it to the collection if it does not exist.
Name Type Description
id Object The id of the entity to retrieve or create.
Returns:
The new or existing object.

remove(entity)Boolean

Removes an entity from the collection.
Name Type Description
entity Entity The entity to be added.
Returns:
true if the item was removed, false if it did not exist in the collection.

removeAll()

Removes all Entities from the collection.

removeById(id)Boolean

Removes an entity with the provided id from the collection.
Name Type Description
id Object The id of the entity to remove.
Returns:
true if the item was removed, false if no item with the provided id existed in the collection.

resumeEvents()

Resumes raising EntityCollection#collectionChanged events immediately when an item is added or removed. Any modifications made while while events were suspended will be triggered as a single event when this function is called. This function is reference counted and can safely be called multiple times as long as there are corresponding calls to EntityCollection#resumeEvents.
Throws:
  • DeveloperError : resumeEvents can not be called before suspendEvents.

suspendEvents()

Prevents EntityCollection#collectionChanged events from being raised until a corresponding call is made to EntityCollection#resumeEvents, at which point a single event will be raised that covers all suspended operations. This allows for many items to be added and removed efficiently. This function can be safely called multiple times as long as there are corresponding calls to EntityCollection#resumeEvents.