GridItemPattern.GridItemPatternInformation.Column Property

Reference

Definition

Namespace:: System.Windows.Automation

Assembly:: UIAutomationClient.dll

Important

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Gets the ordinal number of the column that contains the cell or item.

public:
 property int Column { int get(); };

public int Column { get; }

member this.Column : int

Public ReadOnly Property Column As Integer

Property Value

Int32

A zero-based ordinal number that identifies the column containing the cell or item. The default value is 0.

Examples

In the following example, an AutomationFocusChangedEvent listener is declared to track the traversal of grid items within a grid container. Item properties are echoed to the console upon each focus-changed event.

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

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

    return gridItemPattern;
}

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

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

    Return gridItemPattern

End Function 'GetGridItemPattern

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

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

    return gridPattern;
}

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

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

    Return gridPattern
End Function 'GetGridPattern

///--------------------------------------------------------------------
/// <summary>
/// Set up grid item event listeners.
/// </summary>
/// <param name="targetControl">
/// The grid item container of interest.
/// </param>
///--------------------------------------------------------------------
private void SetGridItemEventListeners(AutomationElement targetControl)
{
    AutomationFocusChangedEventHandler gridItemFocusChangedListener =
        new AutomationFocusChangedEventHandler(OnGridItemFocusChange);
    Automation.AddAutomationFocusChangedEventHandler(
        gridItemFocusChangedListener);
}

'''--------------------------------------------------------------------
''' <summary>
''' Set up grid item event listeners.
''' </summary>
''' <param name="targetControl">
''' The grid item container of interest.
''' </param>
'''--------------------------------------------------------------------
Private Sub SetGridItemEventListeners( _
ByVal targetControl As AutomationElement)
    Dim gridItemFocusChangedListener As AutomationFocusChangedEventHandler = _
    AddressOf OnGridItemFocusChange
    Automation.AddAutomationFocusChangedEventHandler( _
    gridItemFocusChangedListener)
End Sub

///--------------------------------------------------------------------
/// <summary>
/// Event handler for grid item focus change.
/// Can be used to track traversal of individual grid items 
/// within a grid.
/// </summary>
/// <param name="src">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
///--------------------------------------------------------------------
private void OnGridItemFocusChange(
    object src, AutomationFocusChangedEventArgs e)
{
    // Make sure the element still exists. Elements such as tooltips
    // can disappear before the event is processed.
    AutomationElement sourceElement;
    try
    {
        sourceElement = src as AutomationElement;
    }
    catch (ElementNotAvailableException)
    {
        return;
    }

    // Gets a GridItemPattern from the source of the event.
    GridItemPattern gridItemPattern = 
        GetGridItemPattern(sourceElement);

    if (gridItemPattern == null)
    {
        return;
    }

    // Gets a GridPattern from the grid container.
    GridPattern gridPattern = 
        GetGridPattern(gridItemPattern.Current.ContainingGrid);

    if (gridPattern == null)
    {
        return;
    }

    AutomationElement gridItem = null;
    try
    {
        gridItem = gridPattern.GetItem(
        gridItemPattern.Current.Row, 
        gridItemPattern.Current.Column);
    }
    catch (ArgumentOutOfRangeException)
    {
        // If the requested row coordinate is larger than the RowCount 
        // or the column coordinate is larger than the ColumnCount.
        // -- OR --
        // If either of the requested row or column coordinates 
        // are less than zero.
        // TO DO: error handling.
    }

    // Further event processing can be done at this point.
    // For the purposes of this sample we just report item properties.
    StringBuilder gridItemReport = new StringBuilder();
    gridItemReport.AppendLine(
        gridItemPattern.Current.Row.ToString()).AppendLine(
        gridItemPattern.Current.Column.ToString()).AppendLine(
        gridItemPattern.Current.RowSpan.ToString()).AppendLine(
        gridItemPattern.Current.ColumnSpan.ToString()).AppendLine(
        gridItem.Current.AutomationId.ToString());
    Console.WriteLine(gridItemReport.ToString());
}

///--------------------------------------------------------------------
/// <summary>
/// Handles our application shutdown.
/// </summary>
/// <param name="args">Event arguments.</param>
///--------------------------------------------------------------------
protected override void OnExit(System.Windows.ExitEventArgs args)
{
    Automation.RemoveAllEventHandlers();
    base.OnExit(args);
}

'''--------------------------------------------------------------------
''' <summary>
''' Event handler for grid item focus change.
''' Can be used to track traversal of individual grid items 
''' within a grid.
''' </summary>
''' <param name="src">Object that raised the event.</param>
''' <param name="e">Event arguments.</param>
'''--------------------------------------------------------------------
Private Sub OnGridItemFocusChange( _
ByVal src As Object, ByVal e As AutomationFocusChangedEventArgs)
    ' Make sure the element still exists. Elements such as tooltips
    ' can disappear before the event is processed.
    Dim sourceElement As AutomationElement
    Try
        sourceElement = DirectCast(src, AutomationElement)
    Catch exc As ElementNotAvailableException
        Return
    End Try

    ' Gets a GridItemPattern from the source of the event.
    Dim gridItemPattern As GridItemPattern = _
    GetGridItemPattern(sourceElement)

    If gridItemPattern Is Nothing Then
        Return
    End If

    ' Gets a GridPattern from the grid container.
    Dim gridPattern As GridPattern = _
    GetGridPattern(gridItemPattern.Current.ContainingGrid)

    If gridPattern Is Nothing Then
        Return
    End If

    Dim gridItem As AutomationElement = Nothing
    Try
        gridItem = gridPattern.GetItem( _
        gridItemPattern.Current.Row, gridItemPattern.Current.Column)
    Catch
        ' If the requested row coordinate is larger than the RowCount 
        ' or the column coordinate is larger than the ColumnCount.
        ' -- OR --
        ' If either of the requested row or column coordinates 
        ' are less than zero.
        ' TO DO: error handling.
    End Try

    ' Further event processing can be done at this point.
    ' For the purposes of this sample we just report item properties.
    Dim gridItemReport As New StringBuilder()
    gridItemReport.AppendLine( _
    gridItemPattern.Current.Row.ToString()).AppendLine( _
    gridItemPattern.Current.Column.ToString()).AppendLine( _
    gridItemPattern.Current.RowSpan.ToString()).AppendLine( _
    gridItemPattern.Current.ColumnSpan.ToString()).AppendLine( _
    gridItem.Current.AutomationId.ToString())
    Console.WriteLine(gridItemReport.ToString())

End Sub


'''--------------------------------------------------------------------
''' <summary>
''' Handles our application shutdown.
''' </summary>
''' <param name="args">Event arguments.</param>
'''--------------------------------------------------------------------
Protected Overrides Sub OnExit(ByVal args As System.Windows.ExitEventArgs) 
    Automation.RemoveAllEventHandlers()
    MyBase.OnExit(args)

End Sub

Applies to

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GridItemPattern.GridItemPatternInformation.Column Property

Definition

Property Value

Examples

Applies to

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