Buscar un elemento de UI Automation basándose en una condición de propiedad
Nota
Esta documentación está dirigida a los desarrolladores de .NET Framework que quieran usar las clases de automatización de la interfaz de usuario administradas definidas en el espacio de nombres System.Windows.Automation. Para ver la información más reciente acerca de la automatización de la interfaz de usuario, consulte Windows Automation API: automatización de la interfaz de usuario.
Este artículo contiene código de ejemplo que muestra cómo buscar un elemento dentro del árbol de automatización de la interfaz de usuario según una propiedad o propiedades específicas.
Ejemplo
En el ejemplo siguiente, se especifica un conjunto de condiciones de propiedad que identifican un determinado elemento (o elementos) de interés en el árbol AutomationElement. A continuación, se realiza una búsqueda de todos los elementos coincidentes con el método FindAll que incorpora una serie de operaciones booleanas AndCondition para limitar el número de elementos coincidentes.
Nota
Al buscar desde RootElement, debe intentar obtener solo elementos secundarios directos. Una búsqueda de descendientes puede recorrer en iteración cientos o incluso miles de elementos, lo que posiblemente provocaría un desbordamiento de pila. Si intenta obtener un elemento concreto en un nivel inferior, debe iniciar la búsqueda desde la ventana de aplicación o desde un contenedor en un nivel inferior.
///--------------------------------------------------------------------
/// <summary>
/// Walks the UI Automation tree of the target and reports the control
/// type of each element it finds in the control view to the client.
/// </summary>
/// <param name="targetTreeViewElement">
/// The root of the search on this iteration.
/// </param>
/// <param name="elementIndex">
/// The TreeView index for this iteration.
/// </param>
/// <remarks>
/// This is a recursive function that maps out the structure of the
/// subtree of the target beginning at the AutomationElement passed in
/// as the rootElement on the first call. This could be, for example,
/// an application window.
/// CAUTION: Do not pass in AutomationElement.RootElement. Attempting
/// to map out the entire subtree of the desktop could take a very
/// long time and even lead to a stack overflow.
/// </remarks>
///--------------------------------------------------------------------
private void FindTreeViewDescendants(
AutomationElement targetTreeViewElement, int treeviewIndex)
{
if (targetTreeViewElement == null)
return;
AutomationElement elementNode =
TreeWalker.ControlViewWalker.GetFirstChild(targetTreeViewElement);
while (elementNode != null)
{
Label elementInfo = new Label();
elementInfo.Margin = new Thickness(0);
clientTreeViews[treeviewIndex].Children.Add(elementInfo);
// Compile information about the control.
elementInfoCompile = new StringBuilder();
string controlName =
(elementNode.Current.Name == "") ?
"Unnamed control" : elementNode.Current.Name;
string autoIdName =
(elementNode.Current.AutomationId == "") ?
"No AutomationID" : elementNode.Current.AutomationId;
elementInfoCompile.Append(controlName)
.Append(" (")
.Append(elementNode.Current.ControlType.LocalizedControlType)
.Append(" - ")
.Append(autoIdName)
.Append(")");
// Test for the control patterns of interest for this sample.
object objPattern;
ExpandCollapsePattern expcolPattern;
if (true == elementNode.TryGetCurrentPattern(ExpandCollapsePattern.Pattern, out objPattern))
{
expcolPattern = objPattern as ExpandCollapsePattern;
if (expcolPattern.Current.ExpandCollapseState != ExpandCollapseState.LeafNode)
{
Button expcolButton = new Button();
expcolButton.Margin = new Thickness(0, 0, 0, 5);
expcolButton.Height = 20;
expcolButton.Width = 100;
expcolButton.Content = "ExpandCollapse";
expcolButton.Tag = expcolPattern;
expcolButton.Click +=
new RoutedEventHandler(ExpandCollapse_Click);
clientTreeViews[treeviewIndex].Children.Add(expcolButton);
}
}
TogglePattern togPattern;
if (true == elementNode.TryGetCurrentPattern(TogglePattern.Pattern, out objPattern))
{
togPattern = objPattern as TogglePattern;
Button togButton = new Button();
togButton.Margin = new Thickness(0, 0, 0, 5);
togButton.Height = 20;
togButton.Width = 100;
togButton.Content = "Toggle";
togButton.Tag = togPattern;
togButton.Click += new RoutedEventHandler(Toggle_Click);
clientTreeViews[treeviewIndex].Children.Add(togButton);
}
InvokePattern invPattern;
if (true == elementNode.TryGetCurrentPattern(InvokePattern.Pattern, out objPattern))
{
invPattern = objPattern as InvokePattern;
Button invButton = new Button();
invButton.Margin = new Thickness(0);
invButton.Height = 20;
invButton.Width = 100;
invButton.Content = "Invoke";
invButton.Tag = invPattern;
invButton.Click += new RoutedEventHandler(Invoke_Click);
clientTreeViews[treeviewIndex].Children.Add(invButton);
}
// Display compiled information about the control.
elementInfo.Content = elementInfoCompile;
Separator sep = new Separator();
clientTreeViews[treeviewIndex].Children.Add(sep);
// Iterate to next element.
// elementNode - Current element.
// treeviewIndex - Index of parent TreeView.
FindTreeViewDescendants(elementNode, treeviewIndex);
elementNode =
TreeWalker.ControlViewWalker.GetNextSibling(elementNode);
}
}
'''--------------------------------------------------------------------
''' <summary>
''' Walks the UI Automation tree of the target and reports the control
''' type of each element it finds in the control view to the client.
''' </summary>
''' <param name="targetTreeViewElement">
''' The root of the search on this iteration.
''' </param>
''' <param name="treeviewIndex">
''' The TreeView index for this iteration.
''' </param>
''' <remarks>
''' This is a recursive function that maps out the structure of the
''' subtree beginning at the AutomationElement passed in as
''' rootElement on the first call. This could be, for example,
''' an application window.
''' CAUTION: Do not pass in AutomationElement.RootElement. Attempting
''' to map out the entire subtree of the desktop could take a very
''' long time and even lead to a stack overflow.
''' </remarks>
'''--------------------------------------------------------------------
Private Sub FindTreeViewDescendants( _
ByVal targetTreeViewElement As AutomationElement, _
ByVal treeviewIndex As Integer)
If (IsNothing(targetTreeViewElement)) Then
Return
End If
Dim elementNode As AutomationElement = _
TreeWalker.ControlViewWalker.GetFirstChild(targetTreeViewElement)
While Not (elementNode Is Nothing)
Dim elementInfo As New Label()
elementInfo.Margin = New Thickness(0)
clientTreeViews(treeviewIndex).Children.Add(elementInfo)
' Compile information about the control.
elementInfoCompile = New StringBuilder()
Dim controlName As String
If (elementNode.Current.Name = "") Then
controlName = "Unnamed control"
Else
controlName = elementNode.Current.Name
End If
Dim autoIdName As String
If (elementNode.Current.AutomationId = "") Then
autoIdName = "No AutomationID"
Else
autoIdName = elementNode.Current.AutomationId
End If
elementInfoCompile.Append(controlName).Append(" (") _
.Append(elementNode.Current.ControlType.LocalizedControlType) _
.Append(" - ").Append(autoIdName).Append(")")
' Test for the control patterns of interest for this sample.
Dim objPattern As Object = Nothing
Dim expcolPattern As ExpandCollapsePattern
If True = elementNode.TryGetCurrentPattern(ExpandCollapsePattern.Pattern, objPattern) Then
expcolPattern = DirectCast(objPattern, ExpandCollapsePattern)
If expcolPattern.Current.ExpandCollapseState <> ExpandCollapseState.LeafNode Then
Dim expcolButton As New Button()
expcolButton.Margin = New Thickness(0, 0, 0, 5)
expcolButton.Height = 20
expcolButton.Width = 100
expcolButton.Content = "ExpandCollapse"
expcolButton.Tag = expcolPattern
AddHandler expcolButton.Click, AddressOf ExpandCollapse_Click
clientTreeViews(treeviewIndex).Children.Add(expcolButton)
End If
End If
Dim togPattern As TogglePattern
If True = elementNode.TryGetCurrentPattern(TogglePattern.Pattern, objPattern) Then
togPattern = DirectCast(objPattern, TogglePattern)
Dim togButton As New Button()
togButton.Margin = New Thickness(0, 0, 0, 5)
togButton.Height = 20
togButton.Width = 100
togButton.Content = "Toggle"
togButton.Tag = togPattern
AddHandler togButton.Click, AddressOf Toggle_Click
clientTreeViews(treeviewIndex).Children.Add(togButton)
End If
Dim invPattern As InvokePattern
If True = elementNode.TryGetCurrentPattern(InvokePattern.Pattern, objPattern) Then
invPattern = DirectCast(objPattern, InvokePattern)
Dim invButton As New Button()
invButton.Margin = New Thickness(0)
invButton.Height = 20
invButton.Width = 100
invButton.Content = "Invoke"
invButton.Tag = invPattern
AddHandler invButton.Click, AddressOf Invoke_Click
clientTreeViews(treeviewIndex).Children.Add(invButton)
End If
' Display compiled information about the control.
elementInfo.Content = elementInfoCompile
Dim sep As New Separator()
clientTreeViews(treeviewIndex).Children.Add(sep)
' Iterate to next element.
' elementNode - Current element.
' treeviewIndex - Index of parent TreeView.
FindTreeViewDescendants(elementNode, treeviewIndex)
elementNode = TreeWalker.ControlViewWalker.GetNextSibling(elementNode)
End While
End Sub