PeerWatcher.EnumerationCompleted Event

Definition

Namespace:

Windows.Networking.Proximity

Occurs after a scan operation is complete and all peer apps within wireless range have been found.

// Register
event_token EnumerationCompleted(TypedEventHandler<PeerWatcher, IInspectable const&> const& handler) const;

// Revoke with event_token
void EnumerationCompleted(event_token const* cookie) const;

// Revoke with event_revoker
PeerWatcher::EnumerationCompleted_revoker EnumerationCompleted(auto_revoke_t, TypedEventHandler<PeerWatcher, IInspectable const&> const& handler) const;

public event TypedEventHandler<PeerWatcher,object> EnumerationCompleted;

function onEnumerationCompleted(eventArgs) { /* Your code */ }
peerWatcher.addEventListener("enumerationcompleted", onEnumerationCompleted);
peerWatcher.removeEventListener("enumerationcompleted", onEnumerationCompleted);
- or -
peerWatcher.onenumerationcompleted = onEnumerationCompleted;

Public Custom Event EnumerationCompleted As TypedEventHandler(Of PeerWatcher, Object) 

Event Type

TypedEventHandler<PeerWatcher,Object>

TypedEventHandler<PeerWatcher,IInspectable>

Windows requirements

App capabilities

proximity

Remarks

EnumerationCompleted event is raised when an enumeration looking for peer apps within range is complete.

Important

For Windows Phone 8.x apps, calling PeerFinder.ConnectAsync from within an EnumerationCompleted event handler will fail. Instead, call it outside of this event handler, for example, when the user has explicitly chosen to connect to a peer.

private PeerWatcher _peerWatcher;
private bool _peerWatcherIsRunning = false;
private bool _peerFinderStarted = false;

// The list of peers discovered by the PeerWatcher.
ObservableCollection<PeerInformation> _discoveredPeers = new ObservableCollection<PeerInformation>();
void PeerFinder_StartPeerWatcher(object sender, RoutedEventArgs e)
{
    if (!_peerFinderStarted)
    {
        // PeerFinder must be started first.
        return;
    }

    if (_peerWatcherIsRunning)
    {
        // PeerWatcher is already running.
        return;
    }

    try
    {
        if (_peerWatcher == null)
        {
            _peerWatcher = PeerFinder.CreateWatcher();

            // Add PeerWatcher event handlers. Only add handlers once.
            _peerWatcher.Added += PeerWatcher_Added;
            _peerWatcher.Removed += PeerWatcher_Removed;
            _peerWatcher.Updated += PeerWatcher_Updated;
            _peerWatcher.EnumerationCompleted += PeerWatcher_EnumerationCompleted;
            _peerWatcher.Stopped += PeerWatcher_Stopped;
        }

        // Empty the list of discovered peers.
        _discoveredPeers.Clear();

        // Start the PeerWatcher.
        _peerWatcher.Start();

        _peerWatcherIsRunning = true;
    }
    catch (Exception ex)
    {
        // Exceptions can occur if PeerWatcher.Start is called multiple times or
        // PeerWatcher.Start is called the PeerWatcher is stopping.
    }
}

protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
    if (_peerWatcher != null)
    {
        // Remove event handlers.
        _peerWatcher.Added -= PeerWatcher_Added;
        _peerWatcher.Removed -= PeerWatcher_Removed;
        _peerWatcher.Updated -= PeerWatcher_Updated;
        _peerWatcher.EnumerationCompleted -= PeerWatcher_EnumerationCompleted;
        _peerWatcher.Stopped -= PeerWatcher_Stopped;

        _peerWatcher = null;
    }
}

private void PeerWatcher_EnumerationCompleted(PeerWatcher sender, object o)
{
    var result = Dispatcher.RunAsync(CoreDispatcherPriority.Low, () =>
    {
        lock (this)
        {
            if (_discoveredPeers.Count == 0)
            {
                // No peers discovered for this enumeration.
            }
        }
    });
}

See also

• Proximity and Tapping (C#/VB/C++)
• Proximity sample