AccessibleObject.Navigate(AccessibleNavigation) Método

Definición

Navega hasta otro objeto accesible.Navigates to another accessible object.

public:
 virtual System::Windows::Forms::AccessibleObject ^ Navigate(System::Windows::Forms::AccessibleNavigation navdir);
public virtual System.Windows.Forms.AccessibleObject Navigate (System.Windows.Forms.AccessibleNavigation navdir);
abstract member Navigate : System.Windows.Forms.AccessibleNavigation -> System.Windows.Forms.AccessibleObject
override this.Navigate : System.Windows.Forms.AccessibleNavigation -> System.Windows.Forms.AccessibleObject
Public Overridable Function Navigate (navdir As AccessibleNavigation) As AccessibleObject

Parámetros

navdir
AccessibleNavigation

Uno de los valores de AccessibleNavigation.One of the AccessibleNavigation values.

Devoluciones

AccessibleObject que representa uno de los valores de AccessibleNavigation.An AccessibleObject that represents one of the AccessibleNavigation values.

Excepciones

Error en el intento de navegación.The navigation attempt fails.

Ejemplos

En el ejemplo siguiente se muestra la creación de un control de gráfico con reconocimiento de accesibilidad mediante las clases AccessibleObject y Control.ControlAccessibleObject para exponer información accesible.The following example demonstrates the creation of an accessibility-aware chart control, using the AccessibleObject and Control.ControlAccessibleObject classes to expose accessible information. El control traza dos curvas junto con una leyenda.The control plots two curves along with a legend. La clase ChartControlAccessibleObject, que se deriva de ControlAccessibleObject, se usa en el método CreateAccessibilityInstance para proporcionar información de acceso personalizado para el control Chart.The ChartControlAccessibleObject class, which derives from ControlAccessibleObject, is used in the CreateAccessibilityInstance method to provide custom accessible information for the chart control. Dado que la leyenda del gráfico no es un control basado en Control real, sino que se dibuja mediante el control Chart, no tiene ninguna información accesible integrada.Since the chart legend is not an actual Control -based control, but instead is drawn by the chart control, it does not have any built-in accessible information. Por este motivo, la clase ChartControlAccessibleObject invalida el método GetChild para devolver el @no__t 2 que representa la información accesible de cada parte de la leyenda.Because of this, the ChartControlAccessibleObject class overrides the GetChild method to return the CurveLegendAccessibleObject that represents accessible information for each part of the legend. Cuando una aplicación compatible con acceso utiliza este control, el control puede proporcionar la información accesible necesaria.When an accessible-aware application uses this control, the control can provide the necessary accessible information.

Este código muestra cómo invalidar el método Navigate.This code demonstrates shows overriding the Navigate method. Vea la información general de la clase AccessibleObject para obtener el ejemplo de código completo.See the AccessibleObject class overview for the complete code example.

   // Inner class CurveLegendAccessibleObject represents accessible information
   // associated with the CurveLegend object.
public:
   ref class CurveLegendAccessibleObject: public AccessibleObject
   {
   private:
      CurveLegend^ curveLegend;

   public:
      CurveLegendAccessibleObject( CurveLegend^ curveLegend )
         : AccessibleObject()
      {
         this->curveLegend = curveLegend;
      }


   private:

      property ChartControlAccessibleObject^ ChartControl 
      {

         // Private property that helps get the reference to the parent ChartControl.
         ChartControlAccessibleObject^ get()
         {
            return dynamic_cast<ChartControlAccessibleObject^>(Parent);
         }

      }

   internal:

      property int ID 
      {

         // Internal helper function that returns the ID for this CurveLegend.
         int get()
         {
            for ( int i = 0; i < ChartControl->GetChildCount(); i++ )
            {
               if ( ChartControl->GetChild( i ) == this )
               {
                  return i;
               }

            }
            return  -1;
         }

      }

   public:

      property Rectangle Bounds 
      {

         // Gets the Bounds for the CurveLegend. This is used by accessibility programs.
         virtual Rectangle get() override
         {
            
            // The bounds is in screen coordinates.
            Point loc = curveLegend->Location;
            return Rectangle(curveLegend->chart->PointToScreen( loc ),curveLegend->Size);
         }

      }

      property String^ Name 
      {

         // Gets or sets the Name for the CurveLegend. This is used by accessibility programs.
         virtual String^ get() override
         {
            return curveLegend->Name;
         }

         virtual void set( String^ value ) override
         {
            curveLegend->Name = value;
         }

      }

      property AccessibleObject^ Parent 
      {

         // Gets the Curve Legend Parent's Accessible object.
         // This is used by accessibility programs.
         virtual AccessibleObject^ get() override
         {
            return curveLegend->chart->AccessibilityObject;
         }

      }

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

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

      }

      property AccessibleStates State 
      {

         // Gets the state based on the selection for the CurveLegend.
         // This is used by accessibility programs.
         virtual AccessibleStates get() override
         {
            AccessibleStates state = AccessibleStates::Selectable;
            if ( curveLegend->Selected )
            {
               state = static_cast<AccessibleStates>(state | AccessibleStates::Selected);
            }

            return state;
         }

      }

      // Navigates through siblings of this CurveLegend. This is used by accessibility programs.
      virtual AccessibleObject^ Navigate( AccessibleNavigation navdir ) override
      {
         
         // Uses the internal NavigateFromChild helper function that exists
         // on ChartControlAccessibleObject.
         return ChartControl->NavigateFromChild( this, navdir );
      }


      // Selects or unselects this CurveLegend. This is used by accessibility programs.
      virtual void Select( AccessibleSelection selection ) override
      {
         
         // Uses the internal SelectChild helper function that exists
         // on ChartControlAccessibleObject.
         ChartControl->SelectChild( this, selection );
      }

   };
// Inner class CurveLegendAccessibleObject represents accessible information 
// associated with the CurveLegend object.
public class CurveLegendAccessibleObject : AccessibleObject
{
    private CurveLegend curveLegend;

    public CurveLegendAccessibleObject(CurveLegend curveLegend) : base() 
    {
        this.curveLegend = curveLegend;                    
    }                

    // Private property that helps get the reference to the parent ChartControl.
    private ChartControlAccessibleObject ChartControl
    {   
        get {
            return Parent as ChartControlAccessibleObject;
        }
    }

    // Internal helper function that returns the ID for this CurveLegend.
    internal int ID
    {
        get {
            for(int i = 0; i < ChartControl.GetChildCount(); i++) {
                if (ChartControl.GetChild(i) == this) {
                    return i;
                }
            }
            return -1;
        }
    }

    // Gets the Bounds for the CurveLegend. This is used by accessibility programs.
    public override Rectangle Bounds
    {
        get {                        
            // The bounds is in screen coordinates.
            Point loc = curveLegend.Location;
            return new Rectangle(curveLegend.chart.PointToScreen(loc), curveLegend.Size);
        }
    }

    // Gets or sets the Name for the CurveLegend. This is used by accessibility programs.
    public override string Name
    {
        get {
            return curveLegend.Name;
        }
        set {
            curveLegend.Name = value;                        
        }
    }

    // Gets the Curve Legend Parent's Accessible object.
    // This is used by accessibility programs.
    public override AccessibleObject Parent
    {
        get {
            return curveLegend.chart.AccessibilityObject;
        }
    }

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

    // Gets the state based on the selection for the CurveLegend. 
    // This is used by accessibility programs.
    public override AccessibleStates State 
    {
        get {
            AccessibleStates state = AccessibleStates.Selectable;
            if (curveLegend.Selected) 
            {
                state |= AccessibleStates.Selected;
            }
            return state;
        }
    }

    // Navigates through siblings of this CurveLegend. This is used by accessibility programs.
    public override AccessibleObject Navigate(AccessibleNavigation navdir) 
    {
        // Uses the internal NavigateFromChild helper function that exists
        // on ChartControlAccessibleObject.
        return ChartControl.NavigateFromChild(this, navdir);
    }

    // Selects or unselects this CurveLegend. This is used by accessibility programs.
    public override void Select(AccessibleSelection selection) 
    {
        // Uses the internal SelectChild helper function that exists
        // on ChartControlAccessibleObject.
        ChartControl.SelectChild(this, selection);
    }
}
' Inner class CurveLegendAccessibleObject represents accessible information 
' associated with the CurveLegend object.
Public Class CurveLegendAccessibleObject
    Inherits AccessibleObject

    Private curveLegend As CurveLegend
    
    Public Sub New(curveLegend As CurveLegend)
        Me.curveLegend = curveLegend
    End Sub
    
    ' Private property that helps get the reference to the parent ChartControl.                
    Private ReadOnly Property ChartControl() As ChartControlAccessibleObject
        Get
            Return CType(Parent, ChartControlAccessibleObject)
        End Get
    End Property

    ' Friend helper function that returns the ID for this CurveLegend.                
    Friend ReadOnly Property ID() As Integer
        Get
            Dim i As Integer
            For i = 0 To (ChartControl.GetChildCount()) - 1
                If ChartControl.GetChild(i) Is Me Then
                    Return i
                End If
            Next i
            Return - 1
        End Get
    End Property
    
    ' Gets the Bounds for the CurveLegend. This is used by accessibility programs.
    Public Overrides ReadOnly Property Bounds() As Rectangle
        Get
            ' The bounds is in screen coordinates.
            Dim loc As Point = curveLegend.Location
            Return New Rectangle(curveLegend.chart.PointToScreen(loc), curveLegend.Size)
        End Get
    End Property

    ' Gets or sets the Name for the CurveLegend. This is used by accessibility programs.                
    Public Overrides Property Name() As String
        Get
            Return curveLegend.Name
        End Get
        Set
            curveLegend.Name = value
        End Set
    End Property
    
    ' Gets the Curve Legend Parent's Accessible object.
    ' This is used by accessibility programs.                
    Public Overrides ReadOnly Property Parent() As AccessibleObject
        Get
            Return curveLegend.chart.AccessibilityObject
        End Get
    End Property
    
    ' Gets the role for the CurveLegend. This is used by accessibility programs.                
    Public Overrides ReadOnly Property Role() As AccessibleRole
        Get
            Return System.Windows.Forms.AccessibleRole.StaticText
        End Get
    End Property

    ' Gets the state based on the selection for the CurveLegend. 
    ' This is used by accessibility programs.                
    Public Overrides ReadOnly Property State() As AccessibleStates
        Get
            Dim stateTemp As AccessibleStates = AccessibleStates.Selectable
            If curveLegend.Selected Then
                stateTemp = stateTemp Or AccessibleStates.Selected
            End If
            Return stateTemp
        End Get
    End Property
    
    ' Navigates through siblings of this CurveLegend. This is used by accessibility programs.                
    Public Overrides Function Navigate(navdir As AccessibleNavigation) As AccessibleObject
        ' Use the Friend NavigateFromChild helper function that exists
        ' on ChartControlAccessibleObject.
        Return ChartControl.NavigateFromChild(Me, navdir)
    End Function
    
    ' Selects or unselects this CurveLegend. This is used by accessibility programs.
    Public Overrides Sub [Select](selection As AccessibleSelection)

        ' Use the internal SelectChild helper function that exists
        ' on ChartControlAccessibleObject.
        ChartControl.SelectChild(Me, selection)
    End Sub

End Class

Comentarios

La navegación, espacial y lógica, siempre está restringida a los elementos de la interfaz de usuario dentro de un contenedor.Navigation, both spatial and logical, is always restricted to the user interface elements within a container. Con la navegación espacial, los clientes solo pueden navegar hasta un elemento del mismo nivel del objeto inicial.With spatial navigation, clients can navigate only to a sibling of the starting object. Dependiendo de la marca de navegación utilizada con la navegación lógica, los clientes pueden navegar a un elemento secundario o a un elemento del mismo nivel del objeto inicial.Depending on the navigational flag used with logical navigation, clients can navigate to either a child or to a sibling of the starting object. Este método no cambia la selección o el foco.This method does not change the selection or focus. Para cambiar el foco o seleccionar un objeto, utilice Select.To change the focus or to select an object, use Select. El método Navigate recupera solo los elementos de la interfaz de usuario que tienen una ubicación de pantalla definida.The Navigate method retrieves only user interface elements that have a defined screen location.

Notas a los desarrolladores de herederos

Todos los objetos visuales deben admitir este método.All visual objects must support this method. Si un objeto tiene el estado Invisible, puede producirse un error en la navegación a este objeto oculto.If an object has the state Invisible, navigation to this hidden object might fail. Algunos elementos de interfaz definidos por el sistema, como menús, elementos de menú y menús emergentes, permiten la navegación a objetos que no están visibles.Some system-defined interface elements such as menus, menu items, and pop-up menus allow navigation to objects that are not visible. Sin embargo, otros elementos de la interfaz de usuario definidos por el sistema no lo admiten.However, other system-defined user interface elements do not support this. Si es posible, los servidores deben admitir la navegación a objetos que no estén visibles, pero esta compatibilidad no es necesaria y los clientes no deberían esperar.If possible, servers should support navigation to objects that are not visible, but this support is not required and clients should not expect it.

Se aplica a