AccessibleObject Classe
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Fornece informações que os aplicativos de acessibilidade usam para ajustar a interface do usuário de um aplicativo para usuários com deficiências.
public ref class AccessibleObject : MarshalByRefObject, Accessibility::IAccessible, System::Reflection::IReflectpublic ref class AccessibleObject : System::Runtime::InteropServices::StandardOleMarshalObject, Accessibility::IAccessible, System::Reflection::IReflect[System.Runtime.InteropServices.ComVisible(true)]
public class AccessibleObject : MarshalByRefObject, Accessibility.IAccessible, System.Reflection.IReflect[System.Runtime.InteropServices.ComVisible(true)]
public class AccessibleObject : System.Runtime.InteropServices.StandardOleMarshalObject, Accessibility.IAccessible, System.Reflection.IReflectpublic class AccessibleObject : System.Runtime.InteropServices.StandardOleMarshalObject, Accessibility.IAccessible, System.Reflection.IReflect[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
inherit MarshalByRefObject
interface IReflect
interface IAccessible
interface UnsafeNativeMethods.IEnumVariant
interface UnsafeNativeMethods.IMarshal[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible
interface UnsafeNativeMethods.IEnumVariant
interface UnsafeNativeMethods.IOleWindow[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible
interface UnsafeNativeMethods.IAccessibleEx
interface UnsafeNativeMethods.IServiceProvider
interface UnsafeNativeMethods.IRawElementProviderSimple
interface UnsafeNativeMethods.IRawElementProviderFragment
interface UnsafeNativeMethods.IRawElementProviderFragmentRoot
interface UnsafeNativeMethods.IInvokeProvider
interface UnsafeNativeMethods.IValueProvider
interface UnsafeNativeMethods.IRangeValueProvider
interface UnsafeNativeMethods.IExpandCollapseProvider
interface UnsafeNativeMethods.IToggleProvider
interface UnsafeNativeMethods.ITableProvider
interface UnsafeNativeMethods.ITableItemProvider
interface UnsafeNativeMethods.IGridProvider
interface UnsafeNativeMethods.IGridItemProvider
interface UnsafeNativeMethods.IEnumVariant
interface UnsafeNativeMethods.IOleWindow
interface UnsafeNativeMethods.ILegacyIAccessibleProvider
interface UnsafeNativeMethods.ISelectionProvider
interface UnsafeNativeMethods.ISelectionItemProvider
interface UnsafeNativeMethods.IRawElementProviderHwndOverride
interface UnsafeNativeMethods.IScrollItemProvidertype AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible
interface Interop.UiaCore.IAccessibleEx
interface Interop.Ole32.IServiceProvider
interface Interop.UiaCore.IRawElementProviderSimple
interface Interop.UiaCore.IRawElementProviderFragment
interface Interop.UiaCore.IRawElementProviderFragmentRoot
interface Interop.UiaCore.IInvokeProvider
interface Interop.UiaCore.IValueProvider
interface Interop.UiaCore.IRangeValueProvider
interface Interop.UiaCore.IExpandCollapseProvider
interface Interop.UiaCore.IToggleProvider
interface Interop.UiaCore.ITableProvider
interface Interop.UiaCore.ITableItemProvider
interface Interop.UiaCore.IGridProvider
interface Interop.UiaCore.IGridItemProvider
interface Interop.Oleaut32.IEnumVariant
interface Interop.Ole32.IOleWindow
interface Interop.UiaCore.ILegacyIAccessibleProvider
interface Interop.UiaCore.ISelectionProvider
interface Interop.UiaCore.ISelectionItemProvider
interface Interop.UiaCore.IRawElementProviderHwndOverride
interface Interop.UiaCore.IScrollItemProvider
interface Interop.UiaCore.IMultipleViewProvider
interface Interop.UiaCore.ITextProvider
interface Interop.UiaCore.ITextProvider2type AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible
interface Interop.UiaCore.IAccessibleEx
interface IServiceProvider.Interface
interface Interop.UiaCore.IRawElementProviderSimple
interface Interop.UiaCore.IRawElementProviderFragment
interface Interop.UiaCore.IRawElementProviderFragmentRoot
interface Interop.UiaCore.IInvokeProvider
interface Interop.UiaCore.IValueProvider
interface Interop.UiaCore.IRangeValueProvider
interface Interop.UiaCore.IExpandCollapseProvider
interface Interop.UiaCore.IToggleProvider
interface Interop.UiaCore.ITableProvider
interface Interop.UiaCore.ITableItemProvider
interface Interop.UiaCore.IGridProvider
interface Interop.UiaCore.IGridItemProvider
interface IEnumVARIANT.Interface
interface IOleWindow.Interface
interface Interop.UiaCore.ILegacyIAccessibleProvider
interface Interop.UiaCore.ISelectionProvider
interface Interop.UiaCore.ISelectionItemProvider
interface Interop.UiaCore.IRawElementProviderHwndOverride
interface Interop.UiaCore.IScrollItemProvider
interface Interop.UiaCore.IMultipleViewProvider
interface Interop.UiaCore.ITextProvider
interface Interop.UiaCore.ITextProvider2type AccessibleObject = class
inherit StandardOleMarshalObject
interface IReflect
interface IAccessible.Interface
interface IAccessible
interface IAccessibleEx.Interface
interface IServiceProvider.Interface
interface IRawElementProviderSimple.Interface
interface IRawElementProviderFragment.Interface
interface IRawElementProviderFragmentRoot.Interface
interface IInvokeProvider.Interface
interface IValueProvider.Interface
interface IRangeValueProvider.Interface
interface IExpandCollapseProvider.Interface
interface IToggleProvider.Interface
interface ITableProvider.Interface
interface ITableItemProvider.Interface
interface IGridProvider.Interface
interface IGridItemProvider.Interface
interface IEnumVARIANT.Interface
interface IOleWindow.Interface
interface ILegacyIAccessibleProvider.Interface
interface ISelectionProvider.Interface
interface ISelectionItemProvider.Interface
interface IRawElementProviderHwndOverride.Interface
interface IScrollItemProvider.Interface
interface IMultipleViewProvider.Interface
interface ITextProvider.Interface
interface ITextProvider2.Interface
interface IDispatch.Interface
interface IDispatchEx.InterfacePublic Class AccessibleObject
Inherits MarshalByRefObject
Implements IAccessible, IReflectPublic Class AccessibleObject
Inherits StandardOleMarshalObject
Implements IAccessible, IReflect- Herança
- Herança
- Derivado
- Atributos
- Implementações
Exemplos
O exemplo de código a seguir demonstra a criação de um controle de gráfico com reconhecimento de acessibilidade, usando as classes AccessibleObject e Control.ControlAccessibleObject para expor informações acessíveis. O controle plota duas curvas junto com uma legenda. A classe ChartControlAccessibleObject, que deriva de ControlAccessibleObject, é usada no método CreateAccessibilityInstance para fornecer informações acessíveis personalizadas para o controle de gráfico. Como a legenda do gráfico não é um controle Control -based real, mas, em vez disso, é desenhada pelo controle de gráfico, ela não tem nenhuma informação acessível interna. Por isso, a classe ChartControlAccessibleObject substitui o método GetChild para retornar o CurveLegendAccessibleObject que representa informações acessíveis para cada parte da legenda. Quando um aplicativo com reconhecimento acessível usa esse controle, o controle pode fornecer as informações acessíveis necessárias.
#using <Accessibility.dll>
#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
// Declare a chart control that demonstrates accessibility in Windows Forms.
public ref class ChartControl: public System::Windows::Forms::UserControl
{
public:
ref class ChartControlAccessibleObject;
// forward declaration
// Inner Class that represents a legend for a curve in the chart.
ref class CurveLegend
{
// 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 );
}
};
private:
// class CurveLgendAccessibleObject
String^ name;
ChartControl^ chart;
CurveLegendAccessibleObject^ accObj;
bool selected;
Point location;
public:
CurveLegend( ChartControl^ chart, String^ name )
{
this->chart = chart;
this->name = name;
selected = true;
}
property AccessibleObject^ AccessibilityObject
{
// Gets the accessibility object for the curve legend.
AccessibleObject^ get()
{
if ( accObj == nullptr )
{
accObj = gcnew CurveLegendAccessibleObject( this );
}
return accObj;
}
}
property Rectangle Bounds
{
// Gets the bounds for the curve legend.
Rectangle get()
{
return Rectangle(Location,Size);
}
}
property Point Location
{
// Gets or sets the location for the curve legend.
Point get()
{
return location;
}
void set( Point value )
{
location = value;
chart->Invalidate();
// Notifies the chart of the location change. This is used for
// the accessibility information. AccessibleEvents::LocationChange
// tells the chart the reason for the notification.
chart->AccessibilityNotifyClients( AccessibleEvents::LocationChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
}
}
property String^ Name
{
// Gets or sets the Name for the curve legend.
String^ get()
{
return name;
}
void set( String^ value )
{
if ( name != value )
{
name = value;
chart->Invalidate();
// Notifies the chart of the name change. This is used for
// the accessibility information. AccessibleEvents::NameChange
// tells the chart the reason for the notification.
chart->AccessibilityNotifyClients( AccessibleEvents::NameChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
}
}
}
property bool Selected
{
// Gets or sets the Selected state for the curve legend.
bool get()
{
return selected;
}
void set( bool value )
{
if ( selected != value )
{
selected = value;
chart->Invalidate();
// Notifies the chart of the selection value change. This is used for
// the accessibility information. The AccessibleEvents value depends upon
// if the selection is true (AccessibleEvents::SelectionAdd) or
// false (AccessibleEvents::SelectionRemove).
chart->AccessibilityNotifyClients( selected ? AccessibleEvents::SelectionAdd : AccessibleEvents::SelectionRemove, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
}
}
}
property System::Drawing::Size Size
{
// Gets the Size for the curve legend.
System::Drawing::Size get()
{
int legendHeight = chart->Font->Height + 4;
Graphics^ g = chart->CreateGraphics();
int legendWidth = (int)g->MeasureString( Name, chart->Font ).Width + 4;
return System::Drawing::Size( legendWidth, legendHeight );
}
}
};
private:
// class CurveLegend
CurveLegend^ legend1;
CurveLegend^ legend2;
public:
ChartControl()
{
// The ChartControl draws the chart in the OnPaint .
SetStyle( ControlStyles::ResizeRedraw, true );
SetStyle( ControlStyles::DoubleBuffer, true );
SetStyle( ControlStyles::AllPaintingInWmPaint, true );
this->BackColor = System::Drawing::Color::White;
this->Name = "ChartControl";
this->Click += gcnew System::EventHandler( this, &ChartControl::ChartControl_Click );
this->QueryAccessibilityHelp += gcnew System::Windows::Forms::QueryAccessibilityHelpEventHandler( this, &ChartControl::ChartControl_QueryAccessibilityHelp );
// The CurveLengend is not Control-based, it just
// represents the parts of the legend.
legend1 = gcnew CurveLegend( this,"A" );
legend1->Location = Point(20,30);
legend2 = gcnew CurveLegend( this,"B" );
legend2->Location = Point(20,50);
}
protected:
// Overridden to return the custom AccessibleObject
// for the entire chart.
virtual AccessibleObject^ CreateAccessibilityInstance() override
{
return gcnew ChartControlAccessibleObject( this );
}
virtual void OnPaint( PaintEventArgs^ e ) override
{
// The ChartControl draws the chart in the OnPaint .
System::Windows::Forms::UserControl::OnPaint( e );
Rectangle bounds = this->ClientRectangle;
int border = 5;
// Draws the legends first.
StringFormat^ format = gcnew StringFormat;
format->Alignment = StringAlignment::Center;
format->LineAlignment = StringAlignment::Center;
if ( legend1 != nullptr )
{
if ( legend1->Selected )
{
e->Graphics->FillRectangle( gcnew SolidBrush( Color::Blue ), legend1->Bounds );
}
else
{
e->Graphics->DrawRectangle( Pens::Blue, legend1->Bounds );
}
e->Graphics->DrawString( legend1->Name, this->Font, Brushes::Black, legend1->Bounds, format );
}
if ( legend2 != nullptr )
{
if ( legend2->Selected )
{
e->Graphics->FillRectangle( gcnew SolidBrush( Color::Red ), legend2->Bounds );
}
else
{
e->Graphics->DrawRectangle( Pens::Red, legend2->Bounds );
}
e->Graphics->DrawString( legend2->Name, this->Font, Brushes::Black, legend2->Bounds, format );
}
// Charts out the actual curves that represent data in the Chart.
bounds.Inflate( -border, -border );
array<Point>^ temp1 = {Point(bounds.Left,bounds.Bottom),Point(bounds.Left + bounds.Width / 3,bounds.Top + bounds.Height / 5),Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2),Point(bounds.Right,bounds.Top)};
array<Point>^curve1 = temp1;
array<Point>^ temp2 = {Point(bounds.Left,bounds.Bottom - bounds.Height / 3),Point(bounds.Left + bounds.Width / 3,bounds.Top + bounds.Height / 5),Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2),Point(bounds.Right,bounds.Top + bounds.Height / 2)};
array<Point>^curve2 = temp2;
// Draws the actual curve only if it is selected.
if ( legend1->Selected )
e->Graphics->DrawCurve( Pens::Blue, curve1 );
if ( legend2->Selected )
e->Graphics->DrawCurve( Pens::Red, curve2 );
e->Graphics->DrawRectangle( Pens::Blue, bounds );
}
// Handles the QueryAccessibilityHelp event.
void ChartControl_QueryAccessibilityHelp( Object^ /*sender*/, System::Windows::Forms::QueryAccessibilityHelpEventArgs^ e )
{
e->HelpString = "Displays chart data";
}
// Handles the Click event for the chart.
// Toggles the selection of whatever legend was clicked on
void ChartControl_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
Point pt = this->PointToClient( Control::MousePosition );
if ( legend1->Bounds.Contains( pt ) )
{
legend1->Selected = !legend1->Selected;
}
else
if ( legend2->Bounds.Contains( pt ) )
{
legend2->Selected = !legend2->Selected;
}
}
public:
property array<CurveLegend^>^ Legends
{
// Gets an array of CurveLengends used in the Chart.
array<CurveLegend^>^ get()
{
array<CurveLegend^>^temp3 = {legend1,legend2};
return temp3;
}
}
// 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
};
// class ChartControl
public ref class Form1: public System::Windows::Forms::Form
{
private:
// Test out the Chart Control.
ChartControl^ chart1;
public:
Form1()
{
// Create a chart control and add it to the form.
this->chart1 = gcnew ChartControl;
this->ClientSize = System::Drawing::Size( 920, 566 );
this->chart1->Location = System::Drawing::Point( 47, 16 );
this->chart1->Size = System::Drawing::Size( 600, 400 );
this->Controls->Add( this->chart1 );
}
};
// class Form1
[STAThread]
int main()
{
Application::Run( gcnew Form1 );
}
using System;
using System.Drawing;
using System.Windows.Forms;
namespace ChartControl
{
public class Form1 : System.Windows.Forms.Form
{
// Test out the Chart Control.
private ChartControl chart1;
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
public Form1() {
// Create a chart control and add it to the form.
this.chart1 = new ChartControl();
this.ClientSize = new System.Drawing.Size(920, 566);
this.chart1.Location = new System.Drawing.Point(47, 16);
this.chart1.Size = new System.Drawing.Size(600, 400);
this.Controls.Add(this.chart1);
}
}
// Declare a chart control that demonstrates accessibility in Windows Forms.
public class ChartControl : System.Windows.Forms.UserControl
{
private CurveLegend legend1;
private CurveLegend legend2;
public ChartControl()
{
// The ChartControl draws the chart in the OnPaint override.
SetStyle(ControlStyles.ResizeRedraw, true);
SetStyle(ControlStyles.DoubleBuffer, true);
SetStyle(ControlStyles.AllPaintingInWmPaint, true);
this.BackColor = System.Drawing.Color.White;
this.Name = "ChartControl";
this.Click += new System.EventHandler(this.ChartControl_Click);
this.QueryAccessibilityHelp +=
new System.Windows.Forms.QueryAccessibilityHelpEventHandler(
this.ChartControl_QueryAccessibilityHelp);
// The CurveLengend is not Control-based, it just
// represents the parts of the legend.
legend1 = new CurveLegend(this, "A");
legend1.Location = new Point(20, 30);
legend2 = new CurveLegend(this, "B");
legend2.Location = new Point(20, 50);
}
// Overridden to return the custom AccessibleObject
// for the entire chart.
protected override AccessibleObject CreateAccessibilityInstance()
{
return new ChartControlAccessibleObject(this);
}
protected override void OnPaint(PaintEventArgs e)
{
// The ChartControl draws the chart in the OnPaint override.
base.OnPaint(e);
Rectangle bounds = this.ClientRectangle;
int border = 5;
// Draws the legends first.
StringFormat format = new StringFormat();
format.Alignment = StringAlignment.Center;
format.LineAlignment = StringAlignment.Center;
if (legend1 != null) {
if (legend1.Selected) {
e.Graphics.FillRectangle(new SolidBrush(Color.Blue), legend1.Bounds);
} else {
e.Graphics.DrawRectangle(Pens.Blue, legend1.Bounds);
}
e.Graphics.DrawString(legend1.Name, this.Font, Brushes.Black, legend1.Bounds, format);
}
if (legend2 != null) {
if (legend2.Selected) {
e.Graphics.FillRectangle(new SolidBrush(Color.Red), legend2.Bounds);
} else {
e.Graphics.DrawRectangle(Pens.Red, legend2.Bounds);
}
e.Graphics.DrawString(legend2.Name, this.Font, Brushes.Black, legend2.Bounds, format);
}
// Charts out the actual curves that represent data in the Chart.
bounds.Inflate(-border, -border);
Point[] curve1 = new Point[] {new Point(bounds.Left, bounds.Bottom),
new Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5),
new Point(bounds.Right - bounds.Width / 3, (bounds.Top + bounds.Bottom) / 2),
new Point(bounds.Right, bounds.Top)};
Point[] curve2 = new Point[] {new Point(bounds.Left, bounds.Bottom - bounds.Height / 3),
new Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5),
new Point(bounds.Right - bounds.Width / 3, (bounds.Top + bounds.Bottom) / 2),
new Point(bounds.Right, bounds.Top + bounds.Height / 2)};
// Draws the actual curve only if it is selected.
if (legend1.Selected) e.Graphics.DrawCurve(Pens.Blue, curve1);
if (legend2.Selected) e.Graphics.DrawCurve(Pens.Red, curve2);
e.Graphics.DrawRectangle(Pens.Blue, bounds);
}
// Handles the QueryAccessibilityHelp event.
private void ChartControl_QueryAccessibilityHelp(object sender,
System.Windows.Forms.QueryAccessibilityHelpEventArgs e)
{
e.HelpString = "Displays chart data";
}
// Handles the Click event for the chart.
// Toggles the selection of whatever legend was clicked on
private void ChartControl_Click(object sender, System.EventArgs e)
{
Point pt = this.PointToClient(Control.MousePosition);
if (legend1.Bounds.Contains(pt)) {
legend1.Selected = !legend1.Selected;
} else if (legend2.Bounds.Contains(pt)) {
legend2.Selected = !legend2.Selected;
}
}
// Gets an array of CurveLengends used in the Chart.
public CurveLegend[] Legends
{
get {
return new CurveLegend[] { legend1, legend2 };
}
}
// 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 that represents a legend for a curve in the chart.
public class CurveLegend
{
private string name;
private ChartControl chart;
private CurveLegendAccessibleObject accObj;
private bool selected = true;
private Point location;
public CurveLegend(ChartControl chart, string name)
{
this.chart = chart;
this.name = name;
}
// Gets the accessibility object for the curve legend.
public AccessibleObject AccessibilityObject
{
get
{
accObj ??= new CurveLegendAccessibleObject(this);
return accObj;
}
}
// Gets the bounds for the curve legend.
public Rectangle Bounds
{
get
{
return new Rectangle(Location, Size);
}
}
// Gets or sets the location for the curve legend.
public Point Location
{
get {
return location;
}
set {
location = value;
chart.Invalidate();
// Notifies the chart of the location change. This is used for
// the accessibility information. AccessibleEvents.LocationChange
// tells the chart the reason for the notification.
chart.AccessibilityNotifyClients(AccessibleEvents.LocationChange,
((CurveLegendAccessibleObject)AccessibilityObject).ID);
}
}
// Gets or sets the Name for the curve legend.
public string Name
{
get {
return name;
}
set {
if (name != value)
{
name = value;
chart.Invalidate();
// Notifies the chart of the name change. This is used for
// the accessibility information. AccessibleEvents.NameChange
// tells the chart the reason for the notification.
chart.AccessibilityNotifyClients(AccessibleEvents.NameChange,
((CurveLegendAccessibleObject)AccessibilityObject).ID);
}
}
}
// Gets or sets the Selected state for the curve legend.
public bool Selected
{
get {
return selected;
}
set {
if (selected != value)
{
selected = value;
chart.Invalidate();
// Notifies the chart of the selection value change. This is used for
// the accessibility information. The AccessibleEvents value depends upon
// if the selection is true (AccessibleEvents.SelectionAdd) or
// false (AccessibleEvents.SelectionRemove).
chart.AccessibilityNotifyClients(
selected ? AccessibleEvents.SelectionAdd : AccessibleEvents.SelectionRemove,
((CurveLegendAccessibleObject)AccessibilityObject).ID);
}
}
}
// Gets the Size for the curve legend.
public Size Size
{
get {
int legendHeight = chart.Font.Height + 4;
Graphics g = chart.CreateGraphics();
int legendWidth = (int)g.MeasureString(Name, chart.Font).Width + 4;
return new Size(legendWidth, legendHeight);
}
}
// 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);
}
}
}
}
}
Option Explicit
Imports System.Drawing
Imports System.Windows.Forms
Namespace ChartControlNameSpace
Public Class Form1
Inherits System.Windows.Forms.Form
' Test out the Chart Control.
Private chart1 As ChartControl
<System.STAThread()> _
Public Shared Sub Main()
System.Windows.Forms.Application.Run(New Form1())
End Sub
Public Sub New()
' Create a chart control and add it to the form.
Me.chart1 = New ChartControl()
Me.ClientSize = New System.Drawing.Size(920, 566)
Me.chart1.Location = New System.Drawing.Point(47, 16)
Me.chart1.Size = New System.Drawing.Size(600, 400)
Me.Controls.Add(Me.chart1)
End Sub
End Class
' Declares a chart control that demonstrates Accessibility in Windows Forms.
Public Class ChartControl
Inherits System.Windows.Forms.UserControl
Private legend1 As CurveLegend
Private legend2 As CurveLegend
Public Sub New()
' The ChartControl draws the chart in the OnPaint override.
SetStyle(ControlStyles.ResizeRedraw, True)
SetStyle(ControlStyles.DoubleBuffer, True)
SetStyle(ControlStyles.AllPaintingInWmPaint, True)
Me.BackColor = System.Drawing.Color.White
Me.Name = "ChartControl"
' The CurveLengend is not Control-based, it just
' represent the parts of the legend.
legend1 = New CurveLegend(Me, "A")
legend1.Location = New Point(20, 30)
legend2 = New CurveLegend(Me, "B")
legend2.Location = New Point(20, 50)
End Sub
' Overridden to return the custom AccessibleObject
' for the entire chart.
Protected Overrides Function CreateAccessibilityInstance() As AccessibleObject
Return New ChartControlAccessibleObject(Me)
End Function
Protected Overrides Sub OnPaint(e As PaintEventArgs)
' The ChartControl draws the chart in the OnPaint override.
MyBase.OnPaint(e)
Dim bounds As Rectangle = Me.ClientRectangle
Dim border As Integer = 5
' Draw the legends first.
Dim format As New StringFormat()
format.Alignment = StringAlignment.Center
format.LineAlignment = StringAlignment.Center
If (legend1 IsNot Nothing) Then
If legend1.Selected Then
e.Graphics.FillRectangle(New SolidBrush(Color.Blue), legend1.Bounds)
Else
e.Graphics.DrawRectangle(Pens.Blue, legend1.Bounds)
End If
e.Graphics.DrawString(legend1.Name, Me.Font, Brushes.Black, RectangleF.op_Implicit(legend1.Bounds), format)
End If
If (legend2 IsNot Nothing) Then
If legend2.Selected Then
e.Graphics.FillRectangle(New SolidBrush(Color.Red), legend2.Bounds)
Else
e.Graphics.DrawRectangle(Pens.Red, legend2.Bounds)
End If
e.Graphics.DrawString(legend2.Name, Me.Font, Brushes.Black, RectangleF.op_Implicit(legend2.Bounds), format)
End If
' Chart out the actual curves that represent data in the Chart.
bounds.Inflate(-border, -border)
Dim curve1() As Point = {New Point(bounds.Left, bounds.Bottom), _
New Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5), _
New Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2), _
New Point(bounds.Right, bounds.Top)}
Dim curve2() As Point = {New Point(bounds.Left, bounds.Bottom - bounds.Height / 3), _
New Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5), _
New Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2), _
New Point(bounds.Right, bounds.Top + bounds.Height / 2)}
' Draw the actual curve only if it is selected.
If legend1.Selected Then
e.Graphics.DrawCurve(Pens.Blue, curve1)
End If
If legend2.Selected Then
e.Graphics.DrawCurve(Pens.Red, curve2)
End If
e.Graphics.DrawRectangle(Pens.Blue, bounds)
End Sub
' Handle the QueryAccessibilityHelp event.
Private Sub ChartControl_QueryAccessibilityHelp(sender As Object, _
e As System.Windows.Forms.QueryAccessibilityHelpEventArgs) Handles MyBase.QueryAccessibilityHelp
e.HelpString = "Displays chart data"
End Sub
' Handle the Click event for the chart.
' Toggle the selection of whatever legend was clicked.
Private Sub ChartControl_Click(sender As Object, e As System.EventArgs) Handles MyBase.Click
Dim pt As Point = Me.PointToClient(Control.MousePosition)
If legend1.Bounds.Contains(pt) Then
legend1.Selected = Not legend1.Selected
Else
If legend2.Bounds.Contains(pt) Then
legend2.Selected = Not legend2.Selected
End If
End If
End Sub
' Get an array of the CurveLengends used in the Chart.
Public ReadOnly Property Legends() As CurveLegend()
Get
Return New CurveLegend() {legend1, legend2}
End Get
End Property
Protected Sub ExposeAccessibilityNotifyClients(ByVal accEvent As AccessibleEvents, ByVal childID As Integer)
AccessibilityNotifyClients(accEvent, childID)
End Sub
' 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
' Inner Class that represents a legend for a curve in the chart.
Public Class CurveLegend
Private m_name As String
Private chart As ChartControl
Private accObj As CurveLegendAccessibleObject
Private m_selected As Boolean = True
Private m_location As Point
Public Sub New(chart As ChartControl, name As String)
Me.chart = chart
Me.m_name = name
End Sub
' Gets the accessibility object for the curve legend.
Public ReadOnly Property AccessibilityObject() As AccessibleObject
Get
If accObj Is Nothing Then
accObj = New CurveLegendAccessibleObject(Me)
End If
Return accObj
End Get
End Property
' Gets the bounds for the curve legend.
Public ReadOnly Property Bounds() As Rectangle
Get
Return New Rectangle(Location, Size)
End Get
End Property
' Gets or sets the location for the curve legend.
Public Property Location() As Point
Get
Return m_location
End Get
Set
m_location = value
chart.Invalidate()
' Notifies the chart of the location change. This is used for
' the accessibility information. AccessibleEvents.LocationChange
' tells the chart the reason for the notification.
chart.ExposeAccessibilityNotifyClients(AccessibleEvents.LocationChange, _
CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
End Set
End Property
' Gets or sets the Name for the curve legend.
Public Property Name() As String
Get
Return m_name
End Get
Set
If m_name <> value Then
m_name = value
chart.Invalidate()
' Notifies the chart of the name change. This is used for
' the accessibility information. AccessibleEvents.NameChange
' tells the chart the reason for the notification.
chart.ExposeAccessibilityNotifyClients(AccessibleEvents.NameChange, _
CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
End If
End Set
End Property
' Gets or sets the Selected state for the curve legend.
Public Property Selected() As Boolean
Get
Return m_selected
End Get
Set
If m_selected <> value Then
m_selected = value
chart.Invalidate()
' Notifies the chart of the selection value change. This is used for
' the accessibility information. The AccessibleEvents value varies
' on whether the selection is true (AccessibleEvents.SelectionAdd) or
' false (AccessibleEvents.SelectionRemove).
If m_selected Then
chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionAdd, _
CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
Else
chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionRemove, _
CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
End If
End If
End Set
End Property
' Gets the Size for the curve legend.
Public ReadOnly Property Size() As Size
Get
Dim legendHeight As Integer = chart.Font.Height + 4
Dim g As Graphics = chart.CreateGraphics()
Dim legendWidth As Integer = CInt(g.MeasureString(Name, chart.Font).Width) + 4
Return New Size(legendWidth, legendHeight)
End Get
End Property
' 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
End Class
End Class
End Namespace 'ChartControlNameSpace
Comentários
Os aplicativos de acessibilidade podem ajustar os recursos do aplicativo para melhorar a usabilidade dos usuários com deficiências.
Para usuários com deficiência visual, você pode ajustar os recursos de software e sistema operacional para atender às suas necessidades. Por exemplo, você pode ampliar o texto e as imagens e renderizá-las com um contraste. Além disso, você pode acomodar a cegueira de cores com o uso apropriado de cores. Para usuários com deficiência visual grave, os computadores são acessíveis com auxílios de revisão de tela que traduzem o texto na tela para fala ou para uma exibição dinâmica, atualizável e em Braille.
Para usuários com dificuldade de audição, você pode criar programas que usam indicações visuais, como uma barra de ferramentas piscando; ou você pode exibir mensagens faladas como texto. Por exemplo, quando ativado, o recurso SoundSentry, uma opção de acessibilidade no Painel de Controle, fornece um aviso visual sempre que o sistema faz um som de alarme.
Para usuários com deficiências de movimento, você pode projetar controles que refinam ou eliminam o uso de teclado e mouse, melhorando assim a acessibilidade do computador. O Painel de Controle oferece assistência. Por exemplo, uma alternativa é usar o teclado numérico em vez do mouse para navegação. Outra opção, chamada StickyKeys, permite que os usuários que não conseguem segurar duas ou mais chaves de cada vez (como CTRL+P) obtenham o mesmo resultado digitando uma chave de cada vez.
Para usuários com deficiências cognitivas e de linguagem, você pode criar programas de software para atender melhor às suas necessidades. Por exemplo, o uso de sequenciamento visível ou de cued, exibições descomplicadas, menos palavras e um nível de leitura direcionado aos padrões do ensino fundamental podem beneficiar esses usuários.
Para usuários com distúrbios de convulsão, você pode criar programas de software para eliminar padrões de provocação de convulsões.
Para obter mais informações sobre acessibilidade, incluindo informações sobre aplicativos de acessibilidade, consulte recursos de acessibilidade do Windows.
Nota
Para usar o AccessibleObject, você deve adicionar uma referência ao assembly Accessibility instalado com o .NET Framework. O Windows Forms dá suporte apenas à Acessibilidade Ativa 2.0.
Notas aos Herdeiros
Quando você herda dessa classe, pode substituir todos os membros.
Construtores
| AccessibleObject() |
Inicializa uma nova instância da classe AccessibleObject. |
Propriedades
| Bounds |
Obtém o local e o tamanho do objeto acessível. |
| DefaultAction |
Obtém uma cadeia de caracteres que descreve a ação padrão do objeto. Nem todos os objetos têm uma ação padrão. |
| Description |
Obtém uma cadeia de caracteres que descreve a aparência visual do objeto especificado. Nem todos os objetos têm uma descrição. |
| Help |
Obtém uma descrição do que o objeto faz ou como o objeto é usado. |
| KeyboardShortcut |
Obtém a chave de atalho ou a chave de acesso para o objeto acessível. |
| Name |
Obtém ou define o nome do objeto. |
| Parent |
Obtém o pai de um objeto acessível. |
| Role |
Obtém a função desse objeto acessível. |
| State |
Obtém o estado desse objeto acessível. |
| Value |
Obtém ou define o valor de um objeto acessível. |
Métodos
| CreateObjRef(Type) |
Cria um objeto que contém todas as informações relevantes necessárias para gerar um proxy usado para se comunicar com um objeto remoto. (Herdado de MarshalByRefObject) |
| DoDefaultAction() |
Executa a ação padrão associada a esse objeto acessível. |
| Equals(Object) |
Determina se o objeto especificado é igual ao objeto atual. (Herdado de Object) |
| GetChild(Int32) |
Recupera o filho acessível correspondente ao índice especificado. |
| GetChildCount() |
Recupera o número de filhos pertencentes a um objeto acessível. |
| GetFocused() |
Recupera o objeto que tem o foco do teclado. |
| GetHashCode() |
Serve como a função de hash padrão. (Herdado de Object) |
| GetHelpTopic(String) |
Obtém um identificador para um identificador de tópico da Ajuda e o caminho para o arquivo de Ajuda associado a esse objeto acessível. |
| GetLifetimeService() |
Obsoleto.
Recupera o objeto de serviço de tempo de vida atual que controla a política de tempo de vida para essa instância. (Herdado de MarshalByRefObject) |
| GetSelected() |
Recupera o filho selecionado no momento. |
| GetType() |
Obtém o Type da instância atual. (Herdado de Object) |
| HitTest(Int32, Int32) |
Recupera o objeto filho nas coordenadas de tela especificadas. |
| InitializeLifetimeService() |
Obsoleto.
Obtém um objeto de serviço de tempo de vida para controlar a política de tempo de vida dessa instância. (Herdado de MarshalByRefObject) |
| MemberwiseClone() |
Cria uma cópia superficial do Objectatual. (Herdado de Object) |
| MemberwiseClone(Boolean) |
Cria uma cópia superficial do objeto MarshalByRefObject atual. (Herdado de MarshalByRefObject) |
| Navigate(AccessibleNavigation) |
Navega para outro objeto acessível. |
| RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String) |
Gera o evento de notificação de automação da interface do usuário. |
| RaiseLiveRegionChanged() |
Gera o evento de automação da interface do usuário LiveRegionChanged. |
| Select(AccessibleSelection) |
Modifica a seleção ou move o foco do teclado do objeto acessível. |
| ToString() |
Retorna uma cadeia de caracteres que representa o objeto atual. (Herdado de Object) |
| UseStdAccessibleObjects(IntPtr, Int32) |
Associa um objeto a uma instância de um AccessibleObject com base no identificador e na ID do objeto. |
| UseStdAccessibleObjects(IntPtr) |
Associa um objeto a uma instância de um AccessibleObject com base no identificador do objeto. |
Implantações explícitas de interface
| IAccessible.accChildCount |
Obtém o número de interfaces filho que pertencem a esse objeto. Para obter uma descrição desse membro, consulte accChildCount. |
| IAccessible.accDoDefaultAction(Object) |
Executa a ação padrão do objeto especificado. Nem todos os objetos têm uma ação padrão. Para obter uma descrição desse membro, consulte accDoDefaultAction(Object). |
| IAccessible.accFocus |
Obtém o objeto que tem o foco do teclado. Para obter uma descrição desse membro, consulte accFocus. |
| IAccessible.accHitTest(Int32, Int32) |
Obtém o objeto filho nas coordenadas de tela especificadas. Para obter uma descrição desse membro, consulte accHitTest(Int32, Int32). |
| IAccessible.accLocation(Int32, Int32, Int32, Int32, Object) |
Obtém o local da tela atual do objeto. Para obter uma descrição desse membro, consulte accLocation(Int32, Int32, Int32, Int32, Object). |
| IAccessible.accNavigate(Int32, Object) |
Navega até um objeto acessível em relação ao objeto atual. Para obter uma descrição desse membro, consulte accNavigate(Int32, Object). |
| IAccessible.accParent |
Obtém o objeto acessível pai deste objeto. Para obter uma descrição desse membro, consulte accParent. |
| IAccessible.accSelect(Int32, Object) |
Modifica a seleção ou move o foco do teclado do objeto acessível. Para obter uma descrição desse membro, consulte accSelect(Int32, Object). |
| IAccessible.accSelection |
Obtém os objetos filho selecionados de um objeto acessível. Para obter uma descrição desse membro, consulte accSelection. |
| IReflect.GetField(String, BindingFlags) |
Obtém o objeto FieldInfo correspondente ao campo e ao sinalizador de associação especificados. Para obter uma descrição desse membro, consulte GetField(String, BindingFlags). |
| IReflect.GetFields(BindingFlags) |
Obtém uma matriz de objetos FieldInfo correspondentes a todos os campos da classe atual. Para obter uma descrição desse membro, consulte GetFields(BindingFlags). |
| IReflect.GetMember(String, BindingFlags) |
Obtém uma matriz de objetos MemberInfo correspondentes a todos os membros públicos ou a todos os membros que correspondem a um nome especificado. Para obter uma descrição desse membro, consulte GetMember(String, BindingFlags). |
| IReflect.GetMembers(BindingFlags) |
Obtém uma matriz de objetos MemberInfo correspondentes a todos os membros públicos ou a todos os membros da classe atual. Para obter uma descrição desse membro, consulte GetMembers(BindingFlags). |
| IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]) |
Obtém um objeto MethodInfo correspondente a um método especificado, usando uma matriz Type para escolher entre os métodos sobrecarregados. Para obter uma descrição desse membro, consulte GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]). |
| IReflect.GetMethod(String, BindingFlags) |
Obtém um objeto MethodInfo correspondente a um método especificado sob restrições de pesquisa especificadas. Para obter uma descrição desse membro, consulte GetMethod(String, BindingFlags). |
| IReflect.GetMethods(BindingFlags) |
Obtém uma matriz de objetos MethodInfo com todos os métodos públicos ou todos os métodos da classe atual. Para obter uma descrição desse membro, consulte GetMethods(BindingFlags). |
| IReflect.GetProperties(BindingFlags) |
Obtém uma matriz de objetos PropertyInfo correspondentes a todas as propriedades públicas ou a todas as propriedades da classe atual. Para obter uma descrição desse membro, consulte GetProperties(BindingFlags). |
| IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]) |
Obtém um objeto PropertyInfo correspondente a uma propriedade especificada com restrições de pesquisa especificadas. Para obter uma descrição desse membro, consulte GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]). |
| IReflect.GetProperty(String, BindingFlags) |
Obtém um objeto PropertyInfo correspondente a uma propriedade especificada sob restrições de pesquisa especificadas. Para obter uma descrição desse membro, consulte GetProperty(String, BindingFlags). |
| IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]) |
Invoca um membro especificado. Para obter uma descrição desse membro, consulte InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]). |
| IReflect.UnderlyingSystemType |
Obtém o tipo subjacente que representa o objeto IReflect. Para obter uma descrição desse membro, consulte UnderlyingSystemType. |
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