ExpandCollapsePattern.Expand 메서드

정의

네임스페이스:

System.Windows.Automation

어셈블리:

UIAutomationClient.dll

의 모든 자식 노드, 컨트롤 또는 콘텐츠를 AutomationElement표시합니다.

public:
 void Expand();

public void Expand();

member this.Expand : unit -> unit

Public Sub Expand ()

예외

InvalidOperationException

Expand()가 호출되는 경우 ExpandCollapseState = LeafNode

예제

다음 예제 AutomationElement 에서는 메뉴 항목을 나타내는 함수가 현재 ExpandCollapseState항목에 따라 메뉴 항목을 확장하거나 축소하려고 시도하는 함수에 전달됩니다.

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

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

    return expandCollapsePattern;
}

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

    Try
        expandCollapsePattern = DirectCast( _
        targetControl.GetCurrentPattern(expandCollapsePattern.Pattern), _
        ExpandCollapsePattern)
    Catch exc As InvalidOperationException
        ' Object doesn't support the ExpandCollapsePattern control pattern.
        Return Nothing
    End Try

    Return expandCollapsePattern

End Function 'GetExpandCollapsePattern

///--------------------------------------------------------------------
/// <summary>
/// Programmatically expand or collapse a menu item.
/// </summary>
/// <param name="menuItem">
/// The target menu item.
/// </param>
///--------------------------------------------------------------------
private void ExpandCollapseMenuItem(
    AutomationElement menuItem)
{
    if (menuItem == null)
    {
        throw new ArgumentNullException(
            "AutomationElement argument cannot be null.");
    }

    ExpandCollapsePattern expandCollapsePattern =
        GetExpandCollapsePattern(menuItem);

    if (expandCollapsePattern == null)
    {
        return;
    }

    if (expandCollapsePattern.Current.ExpandCollapseState ==
        ExpandCollapseState.LeafNode)
    {
        return;
    }

    try
    {
        if (expandCollapsePattern.Current.ExpandCollapseState == ExpandCollapseState.Expanded)
        {
            // Collapse the menu item.
            expandCollapsePattern.Collapse();
        }
        else if (expandCollapsePattern.Current.ExpandCollapseState == ExpandCollapseState.Collapsed ||
            expandCollapsePattern.Current.ExpandCollapseState == ExpandCollapseState.PartiallyExpanded)
        {
            // Expand the menu item.
            expandCollapsePattern.Expand();
        }
    }
    // Control is not enabled
    catch (ElementNotEnabledException)
    {
        // TO DO: error handling.
    }
    // Control is unable to perform operation.
    catch (InvalidOperationException)
    {
        // TO DO: error handling.
    }
}

'''--------------------------------------------------------------------
''' <summary>
''' Programmatically expand or collapse a menu item.
''' </summary>
''' <param name="menuItem">
''' The target menu item.
''' </param>
'''--------------------------------------------------------------------
Private Sub ExpandCollapseMenuItem(ByVal menuItem As AutomationElement)
    If menuItem Is Nothing Then
        Throw New ArgumentNullException( _
        "AutomationElement argument cannot be null.")
    End If

    Dim expandCollapsePattern As ExpandCollapsePattern = _
    GetExpandCollapsePattern(menuItem)

    If expandCollapsePattern Is Nothing Then
        Return
    End If

    If expandCollapsePattern.Current.ExpandCollapseState = _
    ExpandCollapseState.LeafNode Then
        Return
    End If

    Try
        If expandCollapsePattern.Current.ExpandCollapseState = _
        ExpandCollapseState.Expanded Then
            ' Collapse the menu item.
            expandCollapsePattern.Collapse()

        ElseIf expandCollapsePattern.Current.ExpandCollapseState = _
        ExpandCollapseState.Collapsed OrElse _
        expandCollapsePattern.Current.ExpandCollapseState = _
        ExpandCollapseState.PartiallyExpanded Then
            ' Expand the menu item.
            expandCollapsePattern.Expand()
        End If
    Catch exc As ElementNotEnabledException
        ' Control is not enabled
        ' TO DO: error handling.
    Catch exc As InvalidOperationException
        ' Control is unable to perform operation 
        ' TO DO: error handling.
    End Try

End Sub

설명

확장된 후 AutomationElement 반환되는 차단 메서드입니다.

리프 노드로 표시된 경우 메서드가 호출될 때까지 CollapseExpand 자식 노드가 있는지 여부를 알 수 없는 경우가 AutomationElement 있습니다. 이 동작은 자식 항목의 로드가 지연되는 트리 뷰 컨트롤에서 가능합니다. 예를 들어 현재 자식 항목이 없더라도 Microsoft Windows 탐색기에서 노드의 확장 아이콘을 표시할 수 있습니다. 아이콘을 클릭하면 컨트롤이 자식 항목에 대해 폴링하고 없음을 찾은 다음 확장 아이콘을 제거합니다. 이러한 경우 클라이언트는 메서드에 이벤트 처리기를 AddAutomationPropertyChangedEventHandler 등록하여 속성에서 ExpandCollapseState 속성 변경 이벤트를 수신 대기해야 합니다.

추가 정보

• InvokePattern 및 ExpandCollapsePattern 메뉴 항목 샘플