A Layer that displays dynamic entity observations from real-time services. A dynamic entity layer consumes DynamicEntityObservation objects streamed from a DynamicEntityDataSource. A DynamicEntityDataSource must be passed to the constructor of the layer. The layer manages the display of observations as they are added to or removed from the data source's local cache.
A dynamic entity layer's TrackDisplayProperties allow you to control the display of previous observations by setting a maximum number of observations to show, displaying a line that connects them (track line), and applying renderers to the observations and/or track line.
As with other layers in the ArcGIS Maps SDK, display properties are managed with renderers. In the dynamic entity layer, three renderers are used to control display of observations:
TrackDisplayProperties.previousObservationRenderer: used to control the display of previous observations in a track. All renderer types are supported.
TrackDisplayProperties.trackLineRenderer: used to control the display of the track line between observations. The track line renderer supports only SimpleRenderer (since the track line contains no attributes).
Labels in a dynamic entity layer are controlled through the inherited Layer labeling API. Labels only appear on the latest observation in a track and are not placed on previous observations.
The dynamic entity layer has methods for selecting or unselecting dynamic entities and observations in the display. When selecting a dynamic entity, the selection moves with the entity (the selection halo moves to the latest observation in the track) as new observations are received from the stream. Since observations are static, selected observations appear like any static GeoElement on the display.
Dynamic entity layer also supports identify behavior in a map view or scene view. Be aware that the identify results from this layer consist entirely of DynamicEntityObservation objects. Use the DynamicEntityObservation.getDynamicEntity() method to retrieve the DynamicEntity that the identified observation is associated with.
The track display properties. TrackDisplayProperties allow you to control the display of previous observations in a track by setting a maximum number of observations to show, displaying a line that connects them (track line), and applying renderers to the observations and/or track line.
The unique identifying string for the layer, for example specified in a map or scene. The id is used by other parts of this API to refer to a specific Layer, such as in a set of FeatureFenceParameters or a FacilityLayerDefinition. If not supplied, all layers will be assigned a unique id when created.
Returns the layer content's effective visibility at the specified scale. Returns the effective layer content visibility. This effective visibility takes care of the effective visibility of the parents at the specified scale. Will return false if an error occurs.