SetPreviousObservationsVisibility Method

In This Topic

Specifies whether to display previous observations or not.

Syntax

Visual Basic (Declaration)
C#

Public Sub SetPreviousObservationsVisibility( _
   ByVal previousObservationsVisible As Boolean _
)

public void SetPreviousObservationsVisibility( 
   bool previousObservationsVisible
)

Parameters

previousObservationsVisible: Indicates whether previous observations should be displayed.

Exceptions

Exception	Description
ArcGIS.Core.CalledOnWrongThreadException	This method or property must be called within the lambda passed to QueuedTask.Run.
System.InvalidOperationException	This feature layer does not support tracks.

Remarks

Non-track aware layers will throw a System.InvalidOperationException

Example

Check Previous Observation and Track Line Visibility

{
  //The layer must be track aware and spatial for these settings
  //to have an effect
  if (streamLayer.TrackType != TrackType.Spatial)
  {
    // not track aware and spatial
  }
  // Note: call within QueuedTask.Run()
  {
    if (!streamLayer.AreTrackLinesVisible)
      streamLayer.SetTrackLinesVisibility(true);
    if (!streamLayer.ArePreviousObservationsVisible)
      streamLayer.SetPreviousObservationsVisibility(true);
  }
}

Make Track Lines and Previous Observations Visible

{
  //The layer must be track aware and spatial for these settings
  //to have an effect

  if (streamLayer.TrackType != TrackType.Spatial)
  {
    // not track aware and spatial
  }

  // Note: call within QueuedTask.Run()
  {
    //Note: Setting PreviousObservationsCount larger than the 
    //"SetExpirationMaxCount()" has no effect
    streamLayer.SetPreviousObservationsCount(6);
    if (!streamLayer.AreTrackLinesVisible)
      streamLayer.SetTrackLinesVisibility(true);
    if (!streamLayer.ArePreviousObservationsVisible)
      streamLayer.SetPreviousObservationsVisibility(true);
  }
}

Requirements

Target Platforms: Windows 11 Home, Pro, Enterprise (64 bit)

ArcGIS Pro version: 3.0 or higher.

Reference

FeatureLayer Class
FeatureLayer Members

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