AccessibleSelection AccessibleSelection AccessibleSelection AccessibleSelection Enum

Definition

Gibt an, wie ein barrierefreies Objekt ausgewählt wird oder den Fokus erhält.Specifies how an accessible object is selected or receives focus.

Diese Enumeration weist ein FlagsAttribute-Attribut auf, die eine bitweise Kombination der Memberwerte zulässt.

public enum class AccessibleSelection
[System.Flags]
public enum AccessibleSelection
type AccessibleSelection = 
Public Enum AccessibleSelection
Vererbung
AccessibleSelectionAccessibleSelectionAccessibleSelectionAccessibleSelection
Attribute

Felder

AddSelection AddSelection AddSelection AddSelection 8

Fügt der Auswahl das Objekt hinzu.Adds the object to the selection.

ExtendSelection ExtendSelection ExtendSelection ExtendSelection 4

Markiert alle Objekte zwischen dem Anker und dem ausgewählten Objekt.Selects all objects between the anchor and the selected object.

None None None None 0

Die Auswahl oder der Fokus eines Objekts bleibt unverändert.The selection or focus of an object is unchanged.

RemoveSelection RemoveSelection RemoveSelection RemoveSelection 16

Entfernt das Objekt aus der Auswahl.Removes the object from the selection.

TakeFocus TakeFocus TakeFocus TakeFocus 1

Weist einem Objekt den Fokus zu und legt dieses als Anker, d. h. als Anfangspunkt der Auswahl fest.Assigns focus to an object and makes it the anchor, which is the starting point for the selection. Kann mit TakeSelection, ExtendSelection, AddSelection oder RemoveSelection kombiniert werden.Can be combined with TakeSelection, ExtendSelection, AddSelection, or RemoveSelection.

TakeSelection TakeSelection TakeSelection TakeSelection 2

Wählt das Objekt aus und hebt die Auswahl aller anderen Objekte im Container auf.Selects the object and deselects all other objects in the container.

Beispiele

Das folgende Codebeispiel veranschaulicht die Erstellung eines Barrierefreiheits fähigen Diagramm Steuer Elements mithilfe der- AccessibleObject Klasse Control.ControlAccessibleObject und der-Klasse, um Barrierefreie Informationen verfügbar zu machen.The following code example demonstrates the creation of an accessibility-aware chart control, using the AccessibleObject and Control.ControlAccessibleObject classes to expose accessible information. Das-Steuerelement zeichnet zwei Kurven zusammen mit einer Legende.The control plots two curves along with a legend. Die ChartControlAccessibleObject -Klasse, die von ControlAccessibleObjectabgeleitet wird, wird in CreateAccessibilityInstance der-Methode verwendet, um benutzerdefinierte Informationen für das Diagramm Steuerelement bereitzustellen.The ChartControlAccessibleObject class, which derives from ControlAccessibleObject, is used in the CreateAccessibilityInstance method to provide custom accessible information for the chart control. Da die Diagramm Legende kein tatsächliches Control Steuerelement ist, sondern durch das Diagramm Steuerelement gezeichnet wird, sind keine integrierten zugänglichen Informationen verfügbar.Because the chart legend is not an actual Control -based control, but instead is drawn by the chart control, it does not any built-in accessible information. Aus diesem Grund überschreibt ChartControlAccessibleObject die-Klasse die GetChild -Methode, um CurveLegendAccessibleObject das-Element zurückzugeben, das barrierefreie Informationen für jeden Teil der Legende darstellt.Because of this, the ChartControlAccessibleObject class overrides the GetChild method to return the CurveLegendAccessibleObject that represents accessible information for each part of the legend. Wenn eine barrierefreie Anwendung dieses Steuerelement verwendet, kann das Steuerelement die erforderlichen zugänglichen Informationen bereitstellen.When an accessible-aware application uses this control, the control can provide the necessary accessible information.

In diesem Beispiel wird die AccessibleSelection Verwendung der-Enumeration mit der Select -Methode veranschaulicht.This example demonstrates using the AccessibleSelection enumeration with the Select method. Das gesamte AccessibleObject Codebeispiel finden Sie in der Übersicht über die-Klasse.See the AccessibleObject class overview for the complete code example.

// Inner class ChartControlAccessibleObject represents accessible information associated with the ChartControl.
// The ChartControlAccessibleObject is returned in the ChartControl::CreateAccessibilityInstance .
ref class ChartControlAccessibleObject: public ControlAccessibleObject
{
private:
   ChartControl^ chartControl;

public:
   ChartControlAccessibleObject( ChartControl^ ctrl )
      : ControlAccessibleObject( ctrl )
   {
      chartControl = ctrl;
   }


   property System::Windows::Forms::AccessibleRole Role 
   {

      // Gets the role for the Chart. This is used by accessibility programs.
      virtual System::Windows::Forms::AccessibleRole get() override
      {
         return ::AccessibleRole::Chart;
      }

   }

   property AccessibleStates State 
   {

      // Gets the state for the Chart. This is used by accessibility programs.
      virtual AccessibleStates get() override
      {
         return AccessibleStates::ReadOnly;
      }

   }

   // The CurveLegend objects are "child" controls in terms of accessibility so
   // return the number of ChartLengend objects.
   virtual int GetChildCount() override
   {
      return chartControl->Legends->Length;
   }


   // Gets the Accessibility object of the child CurveLegend idetified by index.
   virtual AccessibleObject^ GetChild( int index ) override
   {
      if ( index >= 0 && index < chartControl->Legends->Length )
      {
         return chartControl->Legends[ index ]->AccessibilityObject;
      }

      return nullptr;
   }


internal:

   // Helper function that is used by the CurveLegend's accessibility object
   // to navigate between sibiling controls. Specifically, this function is used in
   // the CurveLegend::CurveLegendAccessibleObject.Navigate function.
   AccessibleObject^ NavigateFromChild( CurveLegend::CurveLegendAccessibleObject^ child, AccessibleNavigation navdir )
   {
      switch ( navdir )
      {
         case AccessibleNavigation::Down:
         case AccessibleNavigation::Next:
            return GetChild( child->ID + 1 );

         case AccessibleNavigation::Up:
         case AccessibleNavigation::Previous:
            return GetChild( child->ID - 1 );
      }
      return nullptr;
   }


   // Helper function that is used by the CurveLegend's accessibility object
   // to select a specific CurveLegend control. Specifically, this function is used
   // in the CurveLegend::CurveLegendAccessibleObject.Select function.
   void SelectChild( CurveLegend::CurveLegendAccessibleObject^ child, AccessibleSelection selection )
   {
      int childID = child->ID;
      
      // Determine which selection action should occur, based on the
      // AccessibleSelection value.
      if ( (selection & AccessibleSelection::TakeSelection) != (AccessibleSelection)0 )
      {
         for ( int i = 0; i < chartControl->Legends->Length; i++ )
         {
            if ( i == childID )
            {
               chartControl->Legends[ i ]->Selected = true;
            }
            else
            {
               chartControl->Legends[ i ]->Selected = false;
            }

         }
         
         // AccessibleSelection->AddSelection means that the CurveLegend will be selected.
         if ( (selection & AccessibleSelection::AddSelection) != (AccessibleSelection)0 )
         {
            chartControl->Legends[ childID ]->Selected = true;
         }
         
         // AccessibleSelection->AddSelection means that the CurveLegend will be unselected.
         if ( (selection & AccessibleSelection::RemoveSelection) != (AccessibleSelection)0 )
         {
            chartControl->Legends[ childID ]->Selected = false;
         }
      }
   }

};

// class ChartControlAccessibleObject
// Inner class ChartControlAccessibleObject represents accessible information associated with the ChartControl.
// The ChartControlAccessibleObject is returned in the ChartControl.CreateAccessibilityInstance override.
public class ChartControlAccessibleObject : ControlAccessibleObject
{
    ChartControl chartControl;

    public ChartControlAccessibleObject(ChartControl ctrl) : base(ctrl) 
    {
        chartControl = ctrl;
    }

    // Gets the role for the Chart. This is used by accessibility programs.
    public override AccessibleRole Role
    {  
        get {
            return AccessibleRole.Chart;
        }
    }

    // Gets the state for the Chart. This is used by accessibility programs.
    public override AccessibleStates State
    {  
        get {                    
            return AccessibleStates.ReadOnly;
        }
    }

    // The CurveLegend objects are "child" controls in terms of accessibility so 
    // return the number of ChartLengend objects.
    public override int GetChildCount()
    {  
        return chartControl.Legends.Length;
    }

    // Gets the Accessibility object of the child CurveLegend idetified by index.
    public override AccessibleObject GetChild(int index)
    {  
        if (index >= 0 && index < chartControl.Legends.Length) {
            return chartControl.Legends[index].AccessibilityObject;
        }                
        return null;
    }

    // Helper function that is used by the CurveLegend's accessibility object
    // to navigate between sibiling controls. Specifically, this function is used in
    // the CurveLegend.CurveLegendAccessibleObject.Navigate function.
    internal AccessibleObject NavigateFromChild(CurveLegend.CurveLegendAccessibleObject child, 
                                                AccessibleNavigation navdir) 
    {  
        switch(navdir) {
            case AccessibleNavigation.Down:
            case AccessibleNavigation.Next:
                return GetChild(child.ID + 1);
                
            case AccessibleNavigation.Up:
            case AccessibleNavigation.Previous:
                return GetChild(child.ID - 1);                        
        }
        return null;
    }

    // Helper function that is used by the CurveLegend's accessibility object
    // to select a specific CurveLegend control. Specifically, this function is used
    // in the CurveLegend.CurveLegendAccessibleObject.Select function.
    internal void SelectChild(CurveLegend.CurveLegendAccessibleObject child, AccessibleSelection selection) 
    {   
        int childID = child.ID;

        // Determine which selection action should occur, based on the
        // AccessibleSelection value.
        if ((selection & AccessibleSelection.TakeSelection) != 0) {
            for(int i = 0; i < chartControl.Legends.Length; i++) {
                if (i == childID) {
                    chartControl.Legends[i].Selected = true;                        
                } else {
                    chartControl.Legends[i].Selected = false;
                }
            }

            // AccessibleSelection.AddSelection means that the CurveLegend will be selected.
            if ((selection & AccessibleSelection.AddSelection) != 0) {
                chartControl.Legends[childID].Selected = true;                        
            }

            // AccessibleSelection.AddSelection means that the CurveLegend will be unselected.
            if ((selection & AccessibleSelection.RemoveSelection) != 0) {
                chartControl.Legends[childID].Selected = false;                        
            }
        }            
    }
}
' Inner Class ChartControlAccessibleObject represents accessible information 
' associated with the ChartControl.
' The ChartControlAccessibleObject is returned in the         ' ChartControl.CreateAccessibilityInstance override.
Public Class ChartControlAccessibleObject
    Inherits Control.ControlAccessibleObject

    Private chartControl As ChartControl
    
    Public Sub New(ctrl As ChartControl)
        MyBase.New(ctrl)
        chartControl = ctrl
    End Sub 'New
    
    ' Get the role for the Chart. This is used by accessibility programs.            
    Public Overrides ReadOnly Property Role() As AccessibleRole
        Get
            Return System.Windows.Forms.AccessibleRole.Chart
        End Get
    End Property
    
    ' Get the state for the Chart. This is used by accessibility programs.            
    Public Overrides ReadOnly Property State() As AccessibleStates
        Get
            Return AccessibleStates.ReadOnly
        End Get
    End Property                        
    
    ' The CurveLegend objects are "child" controls in terms of accessibility so 
    ' return the number of ChartLengend objects.            
    Public Overrides Function GetChildCount() As Integer
        Return chartControl.Legends.Length
    End Function 
    
    ' Get the Accessibility object of the child CurveLegend idetified by index.
    Public Overrides Function GetChild(index As Integer) As AccessibleObject
        If index >= 0 And index < chartControl.Legends.Length Then
            Return chartControl.Legends(index).AccessibilityObject
        End If
        Return Nothing
    End Function 
    
    ' Helper function that is used by the CurveLegend's accessibility object
    ' to navigate between sibiling controls. Specifically, this function is used in
    ' the CurveLegend.CurveLegendAccessibleObject.Navigate function.
    Friend Function NavigateFromChild(child As CurveLegend.CurveLegendAccessibleObject, _
                                    navdir As AccessibleNavigation) As AccessibleObject
        Select Case navdir
            Case AccessibleNavigation.Down, AccessibleNavigation.Next
                    Return GetChild(child.ID + 1)
            
            Case AccessibleNavigation.Up, AccessibleNavigation.Previous
                    Return GetChild(child.ID - 1)
        End Select
        Return Nothing
    End Function            

    ' Helper function that is used by the CurveLegend's accessibility object
    ' to select a specific CurveLegend control. Specifically, this function is used 
    ' in the CurveLegend.CurveLegendAccessibleObject.Select function.            
    Friend Sub SelectChild(child As CurveLegend.CurveLegendAccessibleObject, selection As AccessibleSelection)
        Dim childID As Integer = child.ID
        
        ' Determine which selection action should occur, based on the
        ' AccessibleSelection value.
        If (selection And AccessibleSelection.TakeSelection) <> 0 Then
            Dim i As Integer
            For i = 0 To chartControl.Legends.Length - 1
                If i = childID Then
                    chartControl.Legends(i).Selected = True
                Else
                    chartControl.Legends(i).Selected = False
                End If
            Next i
            
            ' AccessibleSelection.AddSelection means that the CurveLegend will be selected.
            If (selection And AccessibleSelection.AddSelection) <> 0 Then
                chartControl.Legends(childID).Selected = True
            End If

            ' AccessibleSelection.AddSelection means that the CurveLegend will be unselected.                    
            If (selection And AccessibleSelection.RemoveSelection) <> 0 Then
                chartControl.Legends(childID).Selected = False
            End If
        End If
    End Sub 'SelectChild
End Class 'ChartControlAccessibleObject

Hinweise

Ein Objekt mit Fokus ist das einzige Objekt, das Tastatureingaben empfängt.A focused object is the one object that receives keyboard input. Das Objekt mit dem Tastaturfokus ist entweder das aktive Fenster oder ein untergeordnetes Objekt des aktiven Fensters.The object with the keyboard focus is either the active window or a child object of the active window. Ein ausgewähltes Objekt ist so gekennzeichnet, dass es an einer Art von Gruppen Vorgang beteiligt ist.A selected object is marked to participate in some type of group operation.

Diese Enumeration wird von AccessibleObject.Selectverwendet.This enumeration is used by AccessibleObject.Select.

Weitere Informationen zur Barrierefreiheits Anwendung erhalten Sie, indem Sie in der MSDN-Bibliothek (Microsoft Developer Network) nach "Microsoft Active Accessibility" suchen.For additional information on the accessibility application, search for "Microsoft Active Accessibility" in the Microsoft Developer Network (MSDN) library.

Gilt für:

Siehe auch