Subscribe Method (SnapshotChangedEvent)

In This Topic

Subscribe to the SnapshotChangedEvent.

Syntax

Visual Basic (Declaration)
C#

Public Shared Function Subscribe( _
   ByVal action As Action(Of SnapshotChangedEventArgs), _
   Optional ByVal keepSubscriberAlive As Boolean _
) As SubscriptionToken

public static SubscriptionToken Subscribe( 
   Action<SnapshotChangedEventArgs> action,
   bool keepSubscriberAlive
)

Parameters

action: The delegate that gets executed when the event is published.
keepSubscriberAlive: When false the ArcGIS.Core.Events.CompositePresentationEvent<TPayload> will maintain a weak delegate reference to the subscriber. Using a weak delegate reference relieves the subscriber from the need to unsubscribe to enable proper garbage collection.

Return Value

A ArcGIS.Core.Events.SubscriptionToken that uniquely identifies the added subscription.

Example

Subscribe to Location Snapshot event

{
    SnapshotChangedEvent.Subscribe(OnSnapshotChanged);
    /// Handles changes to a snapshot by processing the provided snapshot data.
    void OnSnapshotChanged(SnapshotChangedEventArgs args)
    {
        if (args == null)
            return;

        var snapshot = args.Snapshot as NMEASnapshot;
        if (snapshot == null)
            return;
        //Note: Run within a QueuedTask
        var pt = snapshot.GetPositionAsMapPoint();
        if (pt?.IsEmpty ?? true)
            return;

        // access properties
        var alt = snapshot.Altitude;
        var dt = snapshot.DateTime;
        var vdop = snapshot.VDOP;
        var hdop = snapshot.HDOP;
        // etc
        //TODO: use the snapshot
    }
}

Requirements

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

ArcGIS Pro version: 3.0 or higher.

Reference

SnapshotChangedEvent Class
SnapshotChangedEvent Members

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