AccessibleSelection Перечисление
Определение
Указывает, как происходит выделение доступного объекта или как он получает фокус.Specifies how an accessible object is selected or receives focus.
Это перечисление имеет атрибут FlagsAttribute, который разрешает побитовое сочетание значений его элементов.
public enum class AccessibleSelection[System.Flags]
public enum AccessibleSelection[<System.Flags>]
type AccessibleSelection = Public Enum AccessibleSelection- Наследование
- Атрибуты
Поля
| AddSelection | 8 | Добавляет объект выделению.Adds the object to the selection. |
| ExtendSelection | 4 | Выделяет все объекты между точкой привязки и выделенным объектом.Selects all objects between the anchor and the selected object. |
| None | 0 | Выделение или фокус объекта не изменяется.The selection or focus of an object is unchanged. |
| RemoveSelection | 16 | Удаляет объект из выделения.Removes the object from the selection. |
| TakeFocus | 1 | Присваивает объекту фокус и делает его точкой привязки, которая является начальной точкой для выделения.Assigns focus to an object and makes it the anchor, which is the starting point for the selection. Допускается использовать вместе с |
| TakeSelection | 2 | Выделяет объект и отменяет выделение всех объектов в контейнере.Selects the object and deselects all other objects in the container. |
Примеры
В следующем примере кода показано создание элемента управления диаграммы с поддержкой специальных возможностей с помощью AccessibleObject Control.ControlAccessibleObject классов и для предоставления доступной информации.The following code example demonstrates the creation of an accessibility-aware chart control, using the AccessibleObject and Control.ControlAccessibleObject classes to expose accessible information. Элемент управления отображает две кривые вместе с условными обозначениями.The control plots two curves along with a legend. ChartControlAccessibleObjectКласс, производный от ControlAccessibleObject , используется в CreateAccessibilityInstance методе для предоставления настраиваемой информации, доступной для элемента управления диаграммы.The ChartControlAccessibleObject class, which derives from ControlAccessibleObject, is used in the CreateAccessibilityInstance method to provide custom accessible information for the chart control. Поскольку условные обозначения диаграммы не являются реальным Control элементом управления, а обрисованы элементом управления диаграммы, он не содержит встроенных доступных сведений.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. Поэтому ChartControlAccessibleObject класс переопределяет GetChild метод для возврата CurveLegendAccessibleObject , который представляет доступную информацию для каждой части условных обозначений.Because of this, the ChartControlAccessibleObject class overrides the GetChild method to return the CurveLegendAccessibleObject that represents accessible information for each part of the legend. Если приложение, поддерживающее доступ, использует этот элемент управления, элемент управления может предоставить необходимые сведения о специальных возможностях.When an accessible-aware application uses this control, the control can provide the necessary accessible information.
В этом примере демонстрируется использование AccessibleSelection перечисления с Select методом.This example demonstrates using the AccessibleSelection enumeration with the Select method. AccessibleObjectПолный пример кода см. в обзоре класса.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
' 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
End Class
Комментарии
Объект с фокусом — это один объект, который получает ввод с клавиатуры.A focused object is the one object that receives keyboard input. Объект с фокусом клавиатуры — это либо активное окно, либо дочерний объект активного окна.The object with the keyboard focus is either the active window or a child object of the active window. Выбранный объект помечен для участия в некоторой операции группы.A selected object is marked to participate in some type of group operation.
Это перечисление используется в AccessibleObject.Select .This enumeration is used by AccessibleObject.Select.
Чтобы получить дополнительные сведения о приложении для специальных возможностей, выполните поиск по запросу "Microsoft Active Accessibility" в библиотеке MSDN.For additional information on the accessibility application, search for "Microsoft Active Accessibility" in the Microsoft Developer Network (MSDN) library.