ScrollItemPattern.ScrollIntoView Méthode

Définition

Espace de noms:

System.Windows.Automation

Assembly:

UIAutomationClient.dll

Fait défiler la zone de contenu d'un objet conteneur pour afficher AutomationElement dans la zone visible (fenêtre d'affichage) du conteneur.

public:
 void ScrollIntoView();

public void ScrollIntoView ();

member this.ScrollIntoView : unit -> unit

Public Sub ScrollIntoView ()

Exceptions

InvalidOperationException

Il n'a pas été possible de faire défiler l'élément dans l'affichage.

Exemples

Dans l’exemple suivant, un gestionnaire d’événements ou RemoveFromSelection un SelectAddToSelection gestionnaire d’événements a été déclaré qui tente de faire défiler un SelectionItemPattern objet dans la région visible de son contrôle de conteneur.

///--------------------------------------------------------------------
/// <summary>
/// Obtains a ScrollItemPattern control pattern from an 
/// automation element.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <returns>
/// A ScrollItemPattern object.
/// </returns>
///--------------------------------------------------------------------
private ScrollItemPattern GetScrollItemPattern(
    AutomationElement targetControl)
{
    ScrollItemPattern scrollItemPattern = null;

    try
    {
        scrollItemPattern =
            targetControl.GetCurrentPattern(
            ScrollItemPattern.Pattern)
            as ScrollItemPattern;
    }
    // Object doesn't support the ScrollItemPattern control pattern
    catch (InvalidOperationException)
    {
        return null;
    }

    return scrollItemPattern;
}

'''--------------------------------------------------------------------
''' <summary>
''' Obtains a ScrollItemPattern control pattern from an 
''' automation element.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
''' <returns>
''' A ScrollItemPattern object.
''' </returns>
'''--------------------------------------------------------------------
Private Function GetScrollItemPattern( _
ByVal targetControl As AutomationElement) As ScrollItemPattern
    Dim scrollItemPattern As ScrollItemPattern = Nothing

    Try
        scrollItemPattern = DirectCast( _
        targetControl.GetCurrentPattern( _
        scrollItemPattern.Pattern), ScrollItemPattern)
    Catch
        ' Object doesn't support the ScrollItemPattern control pattern
        Return Nothing
    End Try

    Return scrollItemPattern

End Function 'GetScrollItemPattern

///--------------------------------------------------------------------
/// <summary>
/// A Select, AddToSelection or RemoveFromSelection event handler that 
/// scrolls a SelectionItem object into the viewable region of its 
/// container control.
/// </summary>
///--------------------------------------------------------------------
private void OnSelectionItemSelect(
    object src, SelectionChangedEventArgs e)
{
    AutomationElement selectionItem = src as AutomationElement;

    ScrollItemPattern scrollItemPattern = GetScrollItemPattern(selectionItem);

    if (scrollItemPattern == null)
    {
        return;
    }

    try
    {
        scrollItemPattern.ScrollIntoView();
    }
    catch (InvalidOperationException)
    {
        // The item cannot be scrolled into view.
        // TO DO: error handling.
    }
}

'''--------------------------------------------------------------------
''' <summary>
''' A Select, AddToSelection or RemoveFromSelection event handler that 
''' scrolls a SelectionItem object into the viewable region of its 
''' container control.
''' </summary>
'''--------------------------------------------------------------------
Private Sub OnSelectionItemSelect( _
ByVal src As Object, ByVal e As SelectionChangedEventArgs)
    Dim selectionItem As AutomationElement = _
    DirectCast(src, AutomationElement)

    Dim scrollItemPattern As ScrollItemPattern = _
    GetScrollItemPattern(selectionItem)

    If scrollItemPattern Is Nothing Then
        Return
    End If

    Try
        scrollItemPattern.ScrollIntoView()
    Catch exc As InvalidOperationException
        ' The item cannot be scrolled into view.
        ' TO DO: error handling.
    End Try

End Sub

Remarques

Cette méthode ne fournit pas la possibilité de spécifier la position dans AutomationElement la région visible (fenêtre d’affichage) du conteneur.