Class: EntityCollection

EntityCollection

new EntityCollection(owner)

Entity object collection. Each entity in the set has a unique identifier, and the set can be monitored.

Name Type Description
owner DataSource | CompositeEntityCollection optional

Create a data source (or composite entity collection) for this collection.

Members

readonly collectionChangedEvent

Gets the event triggered when adding or removing entities from the collection. The generated event is of type EntityCollection.collectionChangedEventCallback.

readonly idString

Get the globally unique identifier of this collection.

readonly ownerDataSource CompositeEntityCollection

Obtain the owner of this entity collection, that is, the data source or composite entity collection that created it.

showBoolean

Get whether this entity collection is displayed. If this property is true, the show property of the entity needs to be set to true in order to be displayed.

swipeEnabledBoolean

Get or set whether the roller shutter is turned on

Default Value:
false

swipeRegionBoundingRectangle

Get or set the rolling shutter area, valid when swineEEnabled is true

readonly valuesArray.<Entity>

Retrieve an array of entities from the collection. This array cannot be directly modified.

Methods

static collectionChangedEventCallback(collection, added, removed, changed)

The event signature generated by the collection change EntityCollection#collectionChanged.

Name Type Description
collection EntityCollection

A collection of triggering events.
added Array.<Entity>

Entity instance array that has been added to the collection.
removed Array.<Entity>

Entity instance array that has been removed from the collection.
changed Array.<Entity>

Modified Entity instance array.

add(entity){Entity}

Add an entity object to the entity collection.

Name Type Description
entity Entity

The entity object to be added.
Throws:

An entity with this ID identifier already exists in the collection.

Type
DeveloperError
Returns:
Type Description
Entity Add successfully returns true, otherwise returns false.

computeAvailability(){TimeInterval}

Calculate the maximum availability of entity objects in the collection. If the collection contains a mixture of available and unavailable data, return the interval of unavailable data. If all data is available, return the interval of available data.

Returns:
Type Description
TimeInterval The availability of entity objects in the collection.

contains(entity){Boolean}

Determine whether the entity object already exists in the collection.

Name Type Description
entity Entity

The specified entity object.
Returns:
Type Description
Boolean The entity object has returned true in the collection, and false if it does not exist.

getById(id){Entity}

Retrieve the entity object with the specified ID.

Name Type Description
id Object

The entity ID to be retrieved.
Returns:
Type Description
Entity Specify the entity object with the specified ID; If there is no entity with this ID in the collection, return undefined.

getOrCreateEntity(id){Entity}

Retrieve an entity object with a specified ID or create an entity object. If the entity object does not exist in the collection, add it to the collection.

Name Type Description
id Object

The ID of the entity object to be retrieved or created.
Returns:
Type Description
Entity Newly created or existing entity objects.

remove(entity){Boolean}

Remove an entity object from the collection.

Name Type Description
entity Entity

The entity object to be removed.
Returns:
Type Description
Boolean Remove successfully and return true; Return false to indicate that this entity does not exist in the collection, removal failed.

removeAll()

Remove all entity objects from the collection.

removeById(id){Boolean}

Remove the entity object with the specified ID from the collection.

Name Type Description
id Object

The entity ID to be removed.
Returns:
Type Description
Boolean Remove successfully and return true; If the entity with the specified ID does not exist in the collection, the removal fails and returns false.

resumeEvents()

When adding or deleting an item, re-trigger the EntityCollection#collectionChanged event. When events are suspended, any modifications made will trigger this event as a single event. The event can be called multiple times as long as a request is made to call EntityCollection#resumeEvents.

Throws:

resumeEvents is triggered after the suspendEvents event.

Type
DeveloperError

suspendEvents()

Before calling EntityCollection#resumeEvents, prevent the EntityCollection#collectionChanged event from being triggered by triggering an event for all stopped operations, which can effectively add or remove many items. As long as a request is made to call EntityCollection#resumeEvents, the event can be called multiple times.