Compartir a través de


Automation.AddAutomationFocusChangedEventHandler Método

Definición

Registra un método que controla los eventos de cambio de foco.

public:
 static void AddAutomationFocusChangedEventHandler(System::Windows::Automation::AutomationFocusChangedEventHandler ^ eventHandler);
public static void AddAutomationFocusChangedEventHandler (System.Windows.Automation.AutomationFocusChangedEventHandler eventHandler);
static member AddAutomationFocusChangedEventHandler : System.Windows.Automation.AutomationFocusChangedEventHandler -> unit
Public Shared Sub AddAutomationFocusChangedEventHandler (eventHandler As AutomationFocusChangedEventHandler)

Parámetros

eventHandler
AutomationFocusChangedEventHandler

Método al que se debe llamar cuando se produzca el evento.

Ejemplos

En el ejemplo siguiente se muestra este método que se usa para agregar un controlador de eventos para los cambios de foco.

AutomationFocusChangedEventHandler focusHandler = null;

/// <summary>
/// Create an event handler and register it.
/// </summary>
public void SubscribeToFocusChange()
{
    focusHandler = new AutomationFocusChangedEventHandler(OnFocusChange);
    Automation.AddAutomationFocusChangedEventHandler(focusHandler);
}

/// <summary>
/// Handle the event.
/// </summary>
/// <param name="src">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
private void OnFocusChange(object src, AutomationFocusChangedEventArgs e)
{
    // TODO Add event handling code.
    // The arguments tell you which elements have lost and received focus.
}

/// <summary>
/// Cancel subscription to the event.
/// </summary>
public void UnsubscribeFocusChange()
{
    if (focusHandler != null)
    {
        Automation.RemoveAutomationFocusChangedEventHandler(focusHandler);
    }
}
Private focusHandler As AutomationFocusChangedEventHandler = Nothing


''' <summary>
''' Create an event handler and register it.
''' </summary>
Public Sub SubscribeToFocusChange()
    focusHandler = New AutomationFocusChangedEventHandler(AddressOf OnFocusChange)
    Automation.AddAutomationFocusChangedEventHandler(focusHandler)

End Sub


''' <summary>
''' Handle the event.
''' </summary>
''' <param name="src">Object that raised the event.</param>
''' <param name="e">Event arguments.</param>
Private Sub OnFocusChange(ByVal src As Object, ByVal e As AutomationFocusChangedEventArgs)

End Sub

' TODO Add event handling code.
' The arguments tell you which elements have lost and received focus.

''' <summary>
''' Cancel subscription to the event.
''' </summary>
Public Sub UnsubscribeFocusChange()
    If (focusHandler IsNot Nothing) Then
        Automation.RemoveAutomationFocusChangedEventHandler(focusHandler)
    End If

End Sub

Comentarios

Los eventos de cambio de foco son en todo el sistema; no se puede establecer un ámbito más estrecho.

eventHandlerpuede ser una instancia del método o una referencia al método (AddressOf en Visual Basic).

Se aplica a

Consulte también