Automation.AddStructureChangedEventHandler Método
Definição
Importante
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Registra o método que manipulará eventos com estrutura alterada.
public:
static void AddStructureChangedEventHandler(System::Windows::Automation::AutomationElement ^ element, System::Windows::Automation::TreeScope scope, System::Windows::Automation::StructureChangedEventHandler ^ eventHandler);
public static void AddStructureChangedEventHandler (System.Windows.Automation.AutomationElement element, System.Windows.Automation.TreeScope scope, System.Windows.Automation.StructureChangedEventHandler eventHandler);
static member AddStructureChangedEventHandler : System.Windows.Automation.AutomationElement * System.Windows.Automation.TreeScope * System.Windows.Automation.StructureChangedEventHandler -> unit
Public Shared Sub AddStructureChangedEventHandler (element As AutomationElement, scope As TreeScope, eventHandler As StructureChangedEventHandler)
Parâmetros
- element
- AutomationElement
O elemento Automação da Interface do Usuário ao qual associar o manipulador de eventos.
- scope
- TreeScope
O escopo de eventos a serem manipulados ou seja, se eles estão no próprio elemento ou em seus ancestrais e descendentes.
- eventHandler
- StructureChangedEventHandler
O método a ser chamado quando ocorre o evento com estrutura alterada.
Exemplos
O exemplo a seguir mostra um delegado do manipulador de eventos com alteração de estrutura que será chamado sempre que a subárvore das alterações especificadas AutomationElement .
/// <summary>
/// Handles structure-changed events. If a new app window has been added, this method ensures
/// it's in the list of runtime IDs and subscribed to window-close events.
/// </summary>
/// <param name="sender">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
/// <remarks>
/// An exception can be thrown by the UI Automation core if the element disappears
/// before it can be processed -- for example, if a menu item is only briefly visible.
/// This exception cannot be caught here because it crosses native/managed boundaries.
/// In the debugger, you can ignore it and continue execution. The exception does not cause
/// a break when the executable is being run.
/// </remarks>
private void OnStructureChanged(object sender, StructureChangedEventArgs e)
{
AutomationElement element = sender as AutomationElement;
if (e.StructureChangeType == StructureChangeType.ChildAdded)
{
Object windowPattern;
if (false == element.TryGetCurrentPattern(WindowPattern.Pattern, out windowPattern))
{
return;
}
int[] rid = e.GetRuntimeId();
if (RuntimeIdListed(rid, savedRuntimeIds) < 0)
{
AddToWindowHandler(element);
savedRuntimeIds.Add(rid);
}
}
}
''' <summary>
''' Handles structure-changed events. If a new app window has been added, this method ensures
''' it's in the list of runtime IDs and subscribed to window-close events.
''' </summary>
''' <param name="sender">Object that raised the event.</param>
''' <param name="e">Event arguments.</param>
''' <remarks>
''' An exception can be thrown by the UI Automation core if the element disappears
''' before it can be processed -- for example, if a menu item is only briefly visible.
''' This exception cannot be caught here because it crosses native/managed boundaries.
''' In the debugger, you can ignore it and continue execution. The exception does not cause
''' a break when the executable is being run.
''' </remarks>
Private Sub OnStructureChanged(ByVal sender As Object, ByVal e As StructureChangedEventArgs)
Dim element As AutomationElement = DirectCast(sender, AutomationElement)
If e.StructureChangeType = StructureChangeType.ChildAdded Then
Dim myWindowPattern As Object = Nothing
If False = element.TryGetCurrentPattern(WindowPattern.Pattern, myWindowPattern) Then
Return
End If
Dim rid As Integer() = e.GetRuntimeId()
If RuntimeIdListed(rid, savedRuntimeIds) < 0 Then
AddToWindowHandler(element)
savedRuntimeIds.Add(rid)
End If
End If
End Sub
O código de exemplo a seguir adiciona uma instância do delegado.
// elementRoot is an AutomationElement.
Automation.AddStructureChangedEventHandler(elementRoot, TreeScope.Children,
new StructureChangedEventHandler(OnStructureChanged));
' elementRoot is an AutomationElement.
Automation.AddStructureChangedEventHandler(elementRoot, TreeScope.Children, New StructureChangedEventHandler(AddressOf OnStructureChanged))
Comentários
eventHandler
pode ser uma instância do método ou uma referência ao método (AddressOf
em Visual Basic).
Aplica-se a
Confira também
- RemoveStructureChangedEventHandler(AutomationElement, StructureChangedEventHandler)
- AddAutomationEventHandler(AutomationEvent, AutomationElement, TreeScope, AutomationEventHandler)
- AddAutomationFocusChangedEventHandler(AutomationFocusChangedEventHandler)
- Assinar eventos de automação de interface do usuário
- Visão geral sobre eventos de automação de interface do usuário