ScrollPattern.Scroll(ScrollAmount, ScrollAmount) Metoda

Definice

Obor názvů:

System.Windows.Automation

Sestavení:

UIAutomationClient.dll

Posune viditelnou oblast oblasti obsahu vodorovně a svisle.

public:
 void Scroll(System::Windows::Automation::ScrollAmount horizontalAmount, System::Windows::Automation::ScrollAmount verticalAmount);

public void Scroll (System.Windows.Automation.ScrollAmount horizontalAmount, System.Windows.Automation.ScrollAmount verticalAmount);

member this.Scroll : System.Windows.Automation.ScrollAmount * System.Windows.Automation.ScrollAmount -> unit

Public Sub Scroll (horizontalAmount As ScrollAmount, verticalAmount As ScrollAmount)

Parametry

horizontalAmount

ScrollAmount

Vodorovné přírůstky specifické pro ovládací prvek. NoScroll pokud ovládací prvek nelze posouvat tímto směrem, měl by být předán.

verticalAmount

ScrollAmount

Svislý přírůstek specifický pro ovládací prvek. NoScroll pokud ovládací prvek nelze posouvat tímto směrem, měl by být předán.

Výjimky

ArgumentException

Ovládací prvek podporuje SmallIncrement hodnoty výhradně pro vodorovné nebo svislé posouvání, ale LargeIncrement hodnota je předána.

InvalidOperationException

Dojde k pokusu o posouvání v nepodporovaném směru.

Příklady

V následujícím příkladu ScrollPattern je řídicí vzor získán z objektu AutomationElement a pak se použije k posouvání požadovaného množství elementu vodorovně nebo svisle.

///--------------------------------------------------------------------
/// <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 scroll the requested amounts.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <param name="hScrollAmount">
/// The requested horizontal scroll amount.
/// </param>
/// <param name="vScrollAmount">
/// The requested vertical scroll amount.
/// </param>
///--------------------------------------------------------------------
private void ScrollElement(
    AutomationElement targetControl,
    ScrollAmount hScrollAmount,
    ScrollAmount vScrollAmount)
{
    if (targetControl == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ScrollPattern scrollPattern = GetScrollPattern(targetControl);

    if (scrollPattern == null)
    {
        return;
    }

    try
    {
        scrollPattern.Scroll(hScrollAmount, 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 scroll the requested amounts.
''' </summary>
''' <param name="targetControl">
''' The automation element of interest.
''' </param>
''' <param name="hScrollAmount">
''' The requested horizontal scroll amount.
''' </param>
''' <param name="vScrollAmount">
''' The requested vertical scroll amount.
''' </param>
'''--------------------------------------------------------------------
Private Sub ScrollElement( _
ByVal targetControl As AutomationElement, _
ByVal hScrollAmount As ScrollAmount, _
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

    Try
        scrollPattern.Scroll(hScrollAmount, 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

Viz také

• ScrollHorizontal(ScrollAmount)
• ScrollVertical(ScrollAmount)