ScrollPattern.ScrollPatternInformation.VerticallyScrollable Propriété

Définition

Espace de noms:

System.Windows.Automation

Assembly:

UIAutomationClient.dll

Récupère une valeur qui indique si l’élément UI Automation peut défiler verticalement.

public:
 property bool VerticallyScrollable { bool get(); };

public bool VerticallyScrollable { get; }

member this.VerticallyScrollable : bool

Public ReadOnly Property VerticallyScrollable As Boolean

Valeur de propriété

Boolean

true si l’élément UI Automation peut défiler horizontalement ; sinon, false. La valeur par défaut est false.

Exemples

Dans l’exemple suivant, un ScrollPattern modèle de contrôle est obtenu à partir d’un élément UI Automation, puis permet de faire défiler verticalement l’élément de la quantité demandée.

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

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

    return scrollPattern;
}

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

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

    Return scrollPattern

End Function 'GetScrollPattern

///--------------------------------------------------------------------
/// <summary>
/// Obtains a ScrollPattern control pattern from an automation 
/// element and attempts to horizontally scroll the requested amount.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <param name="vScrollAmount">
/// The requested vertical scroll amount.
/// </param>
///--------------------------------------------------------------------
private void ScrollElementVertically(
    AutomationElement targetControl,
    ScrollAmount vScrollAmount)
{
    if (targetControl == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ScrollPattern scrollPattern = GetScrollPattern(targetControl);

    if (scrollPattern == null)
    {
        return;
    }
    
    if (!scrollPattern.Current.VerticallyScrollable)
    {
        return;
    }

    try
    {
        scrollPattern.ScrollVertical(vScrollAmount);
    }
    catch (InvalidOperationException)
    {
        // Control not able to scroll in the direction requested;
        // when scrollable property of that direction is False
        // TO DO: error handling.
    }
    catch (ArgumentException)
    {
        // If a control supports SmallIncrement values exclusively 
        // for horizontal or vertical scrolling but a LargeIncrement 
        // value (NaN if not supported) is passed in.
        // TO DO: error handling.
    }
}

'''--------------------------------------------------------------------
''' <summary>
''' Obtains a ScrollPattern control pattern from an automation 
''' element and attempts to horizontally scroll the requested amount.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
''' <param name="vScrollAmount">
''' The requested vertical scroll amount.
''' </param>
'''--------------------------------------------------------------------
Private Sub ScrollElementVertically( _
ByVal targetControl As AutomationElement, _
ByVal vScrollAmount As ScrollAmount)
    If targetControl Is Nothing Then
        Throw New ArgumentNullException( _
        "AutomationElement argument cannot be null.")
    End If

    Dim scrollPattern As ScrollPattern = GetScrollPattern(targetControl)

    If scrollPattern Is Nothing Then
        Return
    End If

    If Not scrollPattern.Current.VerticallyScrollable Then
        Return
    End If

    Try
        scrollPattern.ScrollVertical(vScrollAmount)
    Catch exc As InvalidOperationException
        ' Control not able to scroll in the direction requested;
        ' when scrollable property of that direction is False
        ' TO DO: error handling.
    Catch exc As ArgumentException
        ' If a control supports SmallIncrement values exclusively 
        ' for horizontal or vertical scrolling but a LargeIncrement 
        ' value (NaN if not supported) is passed in.
        ' TO DO: error handling.
    End Try

End Sub

Remarques

Cette propriété peut être dynamique. Par exemple, la zone de contenu de l’élément UI Automation peut ne pas être supérieure à la zone visible actuelle, ce qui signifie VerticallyScrollable que c’est false. Toutefois, le redimensionnement de l’élément UI Automation ou l’ajout d’éléments enfants peut augmenter les limites de la zone de contenu au-delà de la zone visible, indiquant qu’il VerticallyScrollable s’agit truede .