import StreamConnection from "@arcgis/core/layers/support/StreamConnection.js";const StreamConnection = await $arcgis.import("@arcgis/core/layers/support/StreamConnection.js");- Inheritance
- StreamConnection→
Accessor
- Since
- ArcGIS Maps SDK for JavaScript 4.25
A web socket connection to a stream service. The connection to the stream service can be established by calling StreamLayer's connect() method.
- See also
- Example
- // get layer's connection configurationsconst parameters = layer.createConnectionParameters();// set the spatial reference of the service geometriesparameters.spatialReference = new SpatialReference({wkid: 2154});const connection = await layer.connect(parameters);// listen to date-received event once the connection is established// create a graphic from the JSON object returned and add them to viewconnection.on("data-received", (feature) => {const graphic = Graphic.fromJSON(feature);graphic.symbol = myPointSymbol;view.graphics.push(graphic);});// close the connection when it is not needed anymoreconnection.destroy();
Properties
Methods
| Method | Signature | Class |
|---|---|---|
| destroy(): void | | |
| inherited | emit<Type extends EventNames<this>>(type: Type, event?: this["@eventTypes"][Type]): boolean | |
| inherited | hasEventListener<Type extends EventNames<this>>(type: Type): boolean | |
| inherited | on<Type extends EventNames<this>>(type: Type, listener: EventedCallback<this["@eventTypes"][Type]>): ResourceHandle |
destroy
- Signature
-
destroy (): void
Destroys the existing connection instance to the stream service.
- Returns
- void
emit
- Signature
-
emit <Type extends EventNames<this>>(type: Type, event?: this["@eventTypes"][Type]): boolean
- Type parameters
- <Type extends EventNames<this>>
Emits an event on the instance. This method should only be used when creating subclasses of this class.
hasEventListener
- Signature
-
hasEventListener <Type extends EventNames<this>>(type: Type): boolean
- Type parameters
- <Type extends EventNames<this>>
Indicates whether there is an event listener on the instance that matches the provided event name.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| type | Type | The name of the event. | |
- Returns
- boolean
Returns true if the class supports the input event.
on
- Signature
-
on <Type extends EventNames<this>>(type: Type, listener: EventedCallback<this["@eventTypes"][Type]>): ResourceHandle
- Type parameters
- <Type extends EventNames<this>>
Registers an event handler on the instance. Call this method to hook an event with a listener.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| type | Type | An event or an array of events to listen for. | |
| listener | EventedCallback<this["@eventTypes"][Type]> | The function to call when the event fires. | |
- Returns
- ResourceHandle
Returns an event handler with a
remove()method that should be called to stop listening for the event(s).Property Type Description remove Function When called, removes the listener from the event.
- Example
- view.on("click", function(event){// event is the event handle returned after the event fires.console.log(event.mapPoint);});
Events
| Name | Type |
|---|---|
data-received
data-received: CustomEvent<Feature> Fires when the stream connection receives data. The event object contains the message properties received from the stream service.
Type definitions
FeatureMessage
A message to add Features to a StreamLayer on the client by calling its sendMessageToClient() method. An array of JSON Features that can be added to a StreamLayer on the client by calling its sendMessageToClient() method. Each feature is an esri Feature JSON object as defined in the Feature object specification.
DeleteMessage
A message to delete features from a StreamLayer on the client by calling its sendMessageToClient() method.
trackIds
- Type
- number[]
An array of track IDs identifying the features to delete from a StreamLayer on the client.
objectIds
- Type
- ObjectId[]
An array of object IDs identifying the features to delete from a StreamLayer on the client.
ClearMessage
A message to clear all features from a StreamLayer on the client by calling its sendMessageToClient() method.
Message
The message to send to a StreamLayer on the client by calling its sendMessageToClient() method.
- Type
- FeatureMessage | DeleteMessage | ClearMessage | object