CompositeEntityCollection

new Cesium.CompositeEntityCollection(collections, owner)

Non-destructively composites multiple EntityCollection instances into a single collection. If a Entity with the same ID exists in multiple collections, it is non-destructively merged into a single new entity instance. If an entity has the same property in multiple collections, the property of the Entity in the last collection of the list it belongs to is used. CompositeEntityCollection can be used almost anywhere that a EntityCollection is used.
Name Type Description
collections Array.<EntityCollection> optional The initial list of EntityCollection instances to merge.
owner DataSource | CompositeEntityCollection optional The data source (or composite entity collection) which created this collection.

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.

readonlyid : String

Gets a globally unique identifier for this collection.

readonlyowner : DataSource|CompositeEntityCollection

Gets the owner of this composite entity collection, ie. the data source or composite entity collection which created it.

readonlyvalues : Array.<Entity>

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

Methods

addCollection(collection, index)

Adds a collection to the composite.
Name Type Description
collection EntityCollection the collection to add.
index Number optional the index to add the collection at. If omitted, the collection will added on top of all existing collections.
Throws:
  • DeveloperError : index, if supplied, must be greater than or equal to zero and less than or equal to the number of collections.

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.

contains(entity) → Boolean

Returns true if the provided entity is in this collection, false otherwise.
Name Type Description
entity Entity The entity.
Returns:
true if the provided entity is in this collection, false otherwise.

containsCollection(collection) → Boolean

Checks to see if the composite contains a given collection.
Name Type Description
collection EntityCollection the collection to check for.
Returns:
true if the composite contains the collection, false otherwise.

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.

getCollection(index)

Gets a collection by index from the composite.
Name Type Description
index Number the index to retrieve.

getCollectionsLength()

Gets the number of collections in this composite.

indexOfCollection(collection) → Number

Determines the index of a given collection in the composite.
Name Type Description
collection EntityCollection The collection to find the index of.
Returns:
The index of the collection in the composite, or -1 if the collection does not exist in the composite.

lowerCollection(collection)

Lowers a collection down one position in the composite.
Name Type Description
collection EntityCollection the collection to move.
Throws:

lowerCollectionToBottom(collection)

Lowers a collection to the bottom of the composite.
Name Type Description
collection EntityCollection the collection to move.
Throws:

raiseCollection(collection)

Raises a collection up one position in the composite.
Name Type Description
collection EntityCollection the collection to move.
Throws:

raiseCollectionToTop(collection)

Raises a collection to the top of the composite.
Name Type Description
collection EntityCollection the collection to move.
Throws:

removeAllCollections()

Removes all collections from this composite.

removeCollection(collection) → Boolean

Removes a collection from this composite, if present.
Name Type Description
collection EntityCollection The collection to remove.
Returns:
true if the collection was in the composite and was removed, false if the collection was not in the composite.

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 also ensures the collection is recomposited if events are also resumed. 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. While events are suspended, recompositing of the collections will also be suspended, as this can be a costly operation. This function can be safely called multiple times as long as there are corresponding calls to EntityCollection#resumeEvents.