GridPattern.GetItem(Int32, Int32) Méthode

Définition

Espace de noms:

System.Windows.Automation

Assembly:

UIAutomationClient.dll

Récupère un AutomationElement qui représente la cellule spécifiée.

public:
 System::Windows::Automation::AutomationElement ^ GetItem(int row, int column);

public System.Windows.Automation.AutomationElement GetItem (int row, int column);

member this.GetItem : int * int -> System.Windows.Automation.AutomationElement

Public Function GetItem (row As Integer, column As Integer) As AutomationElement

Paramètres

row

Int32

Numéro ordinal de la ligne concernée.

column

Int32

Numéro ordinal de la colonne concernée.

Retours

AutomationElement

AutomationElement qui représente la cellule récupérée.

Exceptions

ArgumentOutOfRangeException

La coordonnée de la ligne ou de la colonne demandée est inférieure à zéro.

- ou -

La coordonnée de la ligne demandée est supérieure à RowCount ou la coordonnée de la colonne est supérieure à ColumnCount.

Exemples

Dans l’exemple suivant, un AutomationFocusChangedEvent écouteur est déclaré pour suivre la traversée des éléments de grille dans un conteneur de grille. Les propriétés d’élément sont répercutées dans la console à chaque événement de changement de focus.

///--------------------------------------------------------------------
/// <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

Remarques

Les coordonnées de grille sont de base zéro, la cellule supérieure gauche (ou la cellule supérieure droite selon les paramètres régionaux) ayant des coordonnées (0,0).

Si une cellule est vide, un élément UI Automation est toujours retourné afin de prendre en charge la récupération de la ContainingGrid propriété pour cette cellule. Cela est possible lorsque la disposition des éléments enfants dans la grille est similaire à un tableau en lambeaux, comme illustré ici.

Exemple de contrôle Grid avec des coordonnées vides