ScrollPattern.ScrollPatternInformation.HorizontallyScrollable Vlastnost

Definice

Obor názvů:

System.Windows.Automation

Sestavení:

UIAutomationClient.dll

Získá hodnotu, která označuje, zda model UI Automation element může posunout vodorovně.

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

public bool HorizontallyScrollable { get; }

member this.HorizontallyScrollable : bool

Public ReadOnly Property HorizontallyScrollable As Boolean

Hodnota vlastnosti

Boolean

truepokud model UI Automation prvek může posunout vodorovně; jinak false. Výchozí hodnota je false.

Příklady

V následujícím příkladu ScrollPattern se řídicí vzor získá z model UI Automation elementu a pak se použije k horizontálnímu posouvání prvku požadované částky.

///--------------------------------------------------------------------
/// <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="hScrollAmount">
/// The requested horizontal scroll amount.
/// </param>
///--------------------------------------------------------------------
private void ScrollElementHorizontally(
    AutomationElement targetControl,
    ScrollAmount hScrollAmount)
{
    if (targetControl == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ScrollPattern scrollPattern = GetScrollPattern(targetControl);

    if (scrollPattern == null)
    {
        return;
    }

    if (!scrollPattern.Current.HorizontallyScrollable)
    {
        return;
    }

    try
    {
        scrollPattern.ScrollHorizontal(hScrollAmount);
    }
    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="hScrollAmount">
''' The requested horizontal scroll amount.
''' </param>
'''--------------------------------------------------------------------
Private Sub ScrollElementHorizontally( _
ByVal targetControl As AutomationElement, _
ByVal hScrollAmount 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.HorizontallyScrollable Then
        Return
    End If

    Try
        scrollPattern.ScrollHorizontal(hScrollAmount)
    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

Poznámky

Tato vlastnost může být dynamická. Například oblast obsahu prvku model UI Automation nemusí být větší než aktuální zobrazitelná oblast, což znamená HorizontallyScrollable false. Změna velikosti prvku model UI Automation nebo přidání podřízených položek však může zvětšit hranice oblasti obsahu nad zobrazitelnou oblast, což znamená HorizontallyScrollable true.