MessageTransmittedHandler Delegado

  • Referencia

Definición

Espacio de nombres:
Windows.Networking.Proximity
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Describe el método que controlará el evento que se desencadena cuando se transmite un mensaje publicado.

public delegate void MessageTransmittedHandler(ProximityDevice ^ sender, long long messageId);
/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.Guid(4020898634, 63202, 19837, 133, 108, 120, 252, 142, 252, 2, 30)]
class MessageTransmittedHandler : MulticastDelegate
[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.Guid(4020898634, 63202, 19837, 133, 108, 120, 252, 142, 252, 2, 30)]
public delegate void MessageTransmittedHandler(ProximityDevice sender, long messageId);
var messageTransmittedHandlerHandler = function(sender, messageId){
/* Your code */
}
Public Delegate Sub MessageTransmittedHandler(sender As ProximityDevice, messageId As Long)

Parámetros

sender
ProximityDevice

Dispositivo de proximidad que publicó el mensaje.

messageId
Int64

long long

long

Identificador de publicación del mensaje.

Atributos
ContractVersionAttribute GuidAttribute

Requisitos de Windows

Familia de dispositivos
Windows 10 (se introdujo en la versión 10.0.10240.0 - for Xbox, see UWP features that aren't yet supported on Xbox)
API contract
Windows.Foundation.UniversalApiContract (se introdujo en la versión v1.0)
Características de aplicaciones
ID_CAP_PROXIMITY [Windows Phone] proximity ID_CAP_PROXIMITY [Windows Phone]

Ejemplos

    Windows.Networking.Proximity.ProximityDevice proximityDevice;
    long publishedMessageId = -1;
    long subscribedMessageId = -1;

    private void initializeProximityDevice()
    {
        proximityDevice = Windows.Networking.Proximity.ProximityDevice.GetDefault();

        if (proximityDevice != null)
        {
            PublishMessageButton.Click += PublishMessage;
            SubscribeForMessageButton.Click += SubscribeForMessage;
            StopSubscribingForMessageButton.Click += StopSubscribingForMessage;
            StopPublishingMessageButton.Click += StopPublishingMessage;
        }
        else
        {
            WriteMessageText("Failed to initialized proximity device.\n");
        }
    }

    private void PublishMessage(object sender, RoutedEventArgs e)
    {
        // Stop publishing the current message.
        if (publishedMessageId != -1)
        {
            proximityDevice.StopPublishingMessage(publishedMessageId);
        }

        publishedMessageId = 
            proximityDevice.PublishMessage("Windows.SampleMessage", MessageTextBlock.Text,
                                                   MessagePublished);
    }

private void MessagePublished(
    Windows.Networking.Proximity.ProximityDevice sender,
        long messageId)
    {
    // The message has been successfully published.
    }

    private void SubscribeForMessage(object sender, RoutedEventArgs e)
    {
        // Only subscribe for the message one time.
        if (subscribedMessageId == -1)
        {
            subscribedMessageId = 
            proximityDevice.SubscribeForMessage("Windows.SampleMessage", messageReceived);
        }
    }

    private void messageReceived(
        Windows.Networking.Proximity.ProximityDevice device, 
        Windows.Networking.Proximity.ProximityMessage message)
    {
        MessageBlock.Text += "Message received: " + message.DataAsString + "\n";
    }

    private void StopSubscribingForMessage(object sender, RoutedEventArgs e)
    {
        proximityDevice.StopSubscribingForMessage(subscribedMessageId);
        subscribedMessageId = -1;
    }

    private void StopPublishingMessage(object sender, RoutedEventArgs e)
    {
        proximityDevice.StopPublishingMessage(publishedMessageId);
        publishedMessageId = -1;
    }

    // Write a message to MessageBlock on the UI thread.
    private Windows.UI.Core.CoreDispatcher messageDispatcher = Window.Current.CoreWindow.Dispatcher;

    async private void WriteMessageText(string message, bool overwrite = false)
    {
        await messageDispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
            () =>
            {
                if (overwrite)
                    MessageBlock.Text = message;
                else
                    MessageBlock.Text += message;
            });
    }

Private proximityDevice As Windows.Networking.Proximity.ProximityDevice
Private publishedMessageId As Long = -1
Private subscribedMessageId As Long = -1

Private Sub initializeProximityDevice()
    proximityDevice = Windows.Networking.Proximity.ProximityDevice.GetDefault()

    If proximityDevice IsNot Nothing Then
        AddHandler PublishMessageButton.Click, AddressOf PublishMessage
        AddHandler SubscribeForMessageButton.Click, AddressOf SubscribeForMessage
        AddHandler StopSubscribingForMessageButton.Click, AddressOf StopSubscribingForMessage
        AddHandler StopPublishingMessageButton.Click, AddressOf StopPublishingMessage
    Else
        WriteMessageText("Failed to initialized proximity device." & vbTab)
    End If
End Sub

Private Sub PublishMessage(sender As Object, e As RoutedEventArgs)
    ' Stop publishing the current message.
    If publishedMessageId <> -1 Then
        proximityDevice.StopPublishingMessage(publishedMessageId)
    End If

    publishedMessageId =
        proximityDevice.PublishMessage("Windows.SampleMessage", MessageTextBlock.Text,
                                       AddressOf MessagePublished)
End Sub

Private Sub MessagePublished(
sender As Windows.Networking.Proximity.ProximityDevice,
    messageId As Long)

' The message has been successfully published.
End Sub

Private Sub SubscribeForMessage(sender As Object, e As RoutedEventArgs)
    ' Only subscribe for the message one time.
    If subscribedMessageId = -1 Then
        subscribedMessageId =
        proximityDevice.SubscribeForMessage("Windows.SampleMessage", AddressOf messageReceived)
    End If
End Sub

Private Sub messageReceived(
    device As Windows.Networking.Proximity.ProximityDevice,
    message As Windows.Networking.Proximity.ProximityMessage)

    MessageBlock.Text &= "Message received: " & message.DataAsString & vbTab
End Sub

Private Sub StopSubscribingForMessage(sender As Object, e As RoutedEventArgs)
    proximityDevice.StopSubscribingForMessage(subscribedMessageId)
    subscribedMessageId = -1
End Sub

Private Sub StopPublishingMessage(sender As Object, e As RoutedEventArgs)
    proximityDevice.StopPublishingMessage(publishedMessageId)
    publishedMessageId = -1
End Sub

' Write a message to MessageBlock on the UI thread.
Private Async Sub WriteMessageText(message As String, Optional overwrite As Boolean = False)
    Await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
        Sub()
            If overwrite Then
                MessageBlock.Text = message
            Else
                MessageBlock.Text &= message
            End If
        End Sub)
End Sub

Comentarios

Los mensajes se siguen publicando hasta que se llama al método StopPublishingMessage o se libera el elemento ProximityDevice en el equipo de publicación. Los mensajes se entregan a todas las aplicaciones que se han suscrito al mismo tipo de mensaje.

Cuando se usa el método PublishMessage , el único tipo de mensaje admitido es aquel que comienza por "Windows.". Para publicar mensajes con otro tipo de mensaje, como "WindowsMime" o "NDEF:WriteTag", debe usar el método PublishBinaryMessage .

Se llama al delegado MessageTransmittedHandler cada vez que un mensaje se transmite correctamente a un dispositivo, independientemente de si alguna aplicación se suscribió al mensaje en ese dispositivo.

Se aplica a

Consulte también