An observable collection of
Entity instances where each entity has a unique id.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
owner |
DataSource | CompositeEntityCollection | 可选 The data source (or composite entity collection) which created this collection. |
成员(属性)
readonly collectionChanged : Event.<EntityCollection.CollectionChangedEventCallback>
Gets the event that is fired when entities are added or removed from the collection.
The generated event is a
EntityCollection.CollectionChangedEventCallback.
Gets a globally unique identifier for this collection.
readonly owner : DataSource|CompositeEntityCollection
Gets the owner of this entity collection, ie. the data source or composite entity collection which created it.
Gets whether or not this entity collection should be
displayed. When true, each entity is only displayed if
its own show property is also true.
readonly values : Array.<Entity>
Gets the array of Entity instances in the collection.
This array should not be modified directly.
方法
add(entity) → Entity
Add an entity to the collection.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
entity |
Entity | Entity.ConstructorOptions | The entity to be added. |
返回值:
The entity that was added.
Throws:
-
DeveloperError : An entity with
already exists in this collection.
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.
返回值:
The availability of entities in the collection.
Returns true if the provided entity is in this collection, false otherwise.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
entity |
Entity | The entity. |
返回值:
true if the provided entity is in this collection, false otherwise.
getById(id) → Entity|undefined
Gets an entity with the specified id.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
id |
string | The id of the entity to retrieve. |
返回值:
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.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
id |
string | The id of the entity to retrieve or create. |
返回值:
The new or existing object.
Removes an entity from the collection.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
entity |
Entity | The entity to be removed. |
返回值:
true if the item was removed, false if it did not exist in the collection.
Removes all Entities from the collection.
Removes an entity with the provided id from the collection.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
id |
string | The id of the entity to remove. |
返回值:
true if the item was removed, false if no item with the provided id existed in the collection.
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.
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.
定义的类型
The signature of the event generated by
EntityCollection#collectionChanged.
| 参数名称 | 类型 | 描述信息 |
|---|---|---|
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. |