IServiceObservable

IServiceObservable exposes IObservable<ServiceEvent>.

/// <summary>Service that can be observed for internal state changes.</summary>
public interface IServiceObservable : IServiceBase, IObservable<ServiceEvent> { }
/// <summary>Base class for service events</summary>
public record ServiceEvent(IServiceBase sender);
/// <summary>Service closed event</summary>
public record ServiceClosedEvent(IServiceBase sender) : ServiceEvent(sender);

.Subscribe(observer) attaches observer to service.

// Create service
IServiceObservable service = (IServiceObservable)Services.Create(ServiceHandlers.Instance);
// Add observer
service.Subscribe(new ServiceObserver());
// Close service
((IDisposable)service).Dispose();

public class ServiceObserver : IObserver<ServiceEvent>
{
    public void OnCompleted() => WriteLine("Completed");
    public void OnError(Exception error) => WriteLine($"Error: {error}");
    public void OnNext(ServiceEvent value) => WriteLine(value);
}

Full Example

Full example

using System;
using Avalanche.Service;
using static System.Console;

public class service_observable
{
    public static void Run()
    {
        {
            // <01>
            // Create service
            IServiceObservable service = (IServiceObservable)Services.Create(ServiceHandlers.Instance);
            // Add observer
            service.Subscribe(new ServiceObserver());
            // Close service
            ((IDisposable)service).Dispose();
            // </01>
        }
    }

    // <99>
    public class ServiceObserver : IObserver<ServiceEvent>
    {
        public void OnCompleted() => WriteLine("Completed");
        public void OnError(Exception error) => WriteLine($"Error: {error}");
        public void OnNext(ServiceEvent value) => WriteLine(value);
    }
    // </99>
}