AccessibleObject AccessibleObject AccessibleObject AccessibleObject Class

Definição

Fornece informações que os aplicativos de acessibilidade usam para ajustar a interface do usuário de um aplicativo para os usuários portadores de deficiências.Provides information that accessibility applications use to adjust an application's user interface (UI) for users with impairments.

public ref class AccessibleObject : System::Runtime::InteropServices::StandardOleMarshalObject, Accessibility::IAccessible, System::Reflection::IReflect
[System.Runtime.InteropServices.ComVisible(true)]
public class AccessibleObject : System.Runtime.InteropServices.StandardOleMarshalObject, Accessibility.IAccessible, System.Reflection.IReflect
type AccessibleObject = class
    inherit StandardOleMarshalObject
    interface IReflect
    interface IAccessible
Public Class AccessibleObject
Inherits StandardOleMarshalObject
Implements IAccessible, IReflect
Herança
AccessibleObjectAccessibleObjectAccessibleObjectAccessibleObject
Derivado
Atributos
Implementações

Exemplos

O exemplo de código a seguir demonstra a criação de um controle de gráfico com reconhecimento de AccessibleObject acessibilidade Control.ControlAccessibleObject , usando as classes e para expor informações acessíveis.The following code example demonstrates the creation of an accessibility-aware chart control, using the AccessibleObject and Control.ControlAccessibleObject classes to expose accessible information. O controle plota duas curvas junto com uma legenda.The control plots two curves along with a legend. A ChartControlAccessibleObject classe, que deriva de ControlAccessibleObject CreateAccessibilityInstance , é usada no método para fornecer informações personalizadas acessíveis para o controle de gráfico.The ChartControlAccessibleObject class, which derives from ControlAccessibleObject, is used in the CreateAccessibilityInstance method to provide custom accessible information for the chart control. Como a legenda do gráfico não é um Control controle baseado em real, mas, em vez disso, é desenhada pelo controle de gráfico, ela não tem informações internas acessíveis.Because 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 isso, a ChartControlAccessibleObject classe substitui o GetChild método para retornar o CurveLegendAccessibleObject que representa informações acessíveis para cada parte da legenda.Because of this, the ChartControlAccessibleObject class overrides the GetChild method to return the CurveLegendAccessibleObject that represents accessible information for each part of the legend. Quando um aplicativo com reconhecimento de acessibilidade usa esse controle, o controle pode fornecer as informações de acessibilidade necessárias.When an accessible-aware application uses this control, the control can provide the necessary accessible information.

#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 {
                    if (accObj == null) {
                        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 'Main

        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 'New
              
        ' 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 'OnPaint
        
        ' 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 'ChartControl_Click

        ' 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 '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

        ' 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 'New

            ' 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 'New
                
                ' 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 'CurveLegendAccessibleObject

        End Class 'CurveLegend

    End Class 'ChartControl

End Namespace 'ChartControlNameSpace

Comentários

Os aplicativos de acessibilidade podem ajustar os recursos do aplicativo para melhorar a usabilidade para usuários com deficiências.Accessibility applications can adjust features of the application to improve usability for users with disabilities.

Para usuários com deficiência visual, você pode ajustar os recursos do software e do sistema operacional para atender às suas necessidades.For users who are visually impaired, you can adjust software and operating system features to comply with their needs. Por exemplo, você pode ampliar o texto e as imagens e renderizá-las com um contraste.For example, you can enlarge text and images and render them with a contrast. Além disso, você pode acomodar a cegueira de cor com o uso apropriado de cores.In addition, you can accommodate color-blindness with the appropriate use of colors. Para usuários que são seriamente prejudicados visualmente, os computadores podem ser acessados com auxílios de revisão de tela que convertem texto na tela em fala ou em uma exibição dinâmica, atualizável e em braile.For users who are severely visually impaired, computers are accessible with screen review aids that translate on-screen text to speech or to a dynamic, refreshable, Braille display.

Para usuários que são difíceis de ouvir, você pode criar programas que usam indicações visuais, como uma barra de ferramentas piscando; ou você pode exibir mensagens faladas como texto.For users who are hard of hearing, you can design programs that use visual cues, such as a flashing toolbar; or you can display spoken messages as text. Por exemplo, quando ativado, o SoundSentry recurso, uma opção de acessibilidade no painel de controle, fornece um aviso visual sempre que o sistema faz um som de alarme.For example, when turned on, the SoundSentry feature, an accessibility option in Control Panel, provides a visual warning whenever the system makes an alarm sound.

Para usuários com deficiências motoras, você pode criar controles que refinam ou eliminem o uso do teclado e do mouse, melhorando assim a acessibilidade do computador.For users with motion disabilities, you can design controls that refine or eliminate keyboard and mouse use, thereby improving computer accessibility. O painel de controle oferece assistência.Control Panel offers assistance. Por exemplo, uma alternativa é usar o teclado numérico em vez do mouse para navegação.For example, one alternative is to use the numeric keypad instead of the mouse for navigation. Outra opção, chamada StickyKeys, habilita os usuários que não podem manter duas ou mais chaves por vez (como CTRL + P) para obter o mesmo resultado digitando uma chave por vez.Another option, called StickyKeys, enables users who cannot hold down two or more keys at a time (such as CTRL+P) to get the same result by typing one key at a time.

Para usuários com deficiências cognitivas e de linguagem, você pode criar programas de software para acomodar melhor suas necessidades.For users with cognitive and language disabilities, you can design software programs to better accommodate their needs. Por exemplo, usando sequenciamento evidente ou cued, exibições incomplicadas, menos palavras e um nível de leitura direcionado a padrões escolares elementares podem beneficiar esses usuários.For example, using conspicuous or cued sequencing, uncomplicated displays, fewer words, and a reading level targeted to elementary school standards can benefit these users.

Para usuários com o autoimunes de captura, você pode criar programas de software para eliminar padrões de provocativa de captura.For users with seizure disorders, you can design software programs to eliminate seizure provoking patterns.

Para obter mais informações sobre acessibilidade, incluindo informações sobre aplicativos de acessibilidade, consulte a documentação do Microsoft Accessibility na biblioteca MSDN ou no site da Microsoft.For more information about accessibility, including information about accessibility applications, see the documentation for Microsoft Accessibility in the MSDN library or at the Microsoft Web site.

Observação

Para usar o AccessibleObject, você deve adicionar uma referência Accessibility ao assembly instalado com o .NET Framework.NET Framework.To use the AccessibleObject, you must add a reference to the Accessibility assembly installed with the .NET Framework.NET Framework. Windows Forms só oferece suporte a Acessibilidade Ativa 2,0.Windows Forms only supports Active Accessibility 2.0.

Notas aos Herdeiros

Ao herdar dessa classe, você pode substituir todos os membros.When you inherit from this class, you can override all the members.

Construtores

AccessibleObject() AccessibleObject() AccessibleObject() AccessibleObject()

Inicializa uma nova instância da classe AccessibleObject.Initializes a new instance of the AccessibleObject class.

Campos

RuntimeIDFirstItem RuntimeIDFirstItem RuntimeIDFirstItem RuntimeIDFirstItem

Propriedades

Bounds Bounds Bounds Bounds

Obtém o local e o tamanho do objeto acessível.Gets the location and size of the accessible object.

DefaultAction DefaultAction DefaultAction DefaultAction

Obtém uma cadeia de caracteres que descreve a ação padrão do objeto.Gets a string that describes the default action of the object. Nem todos os objetos têm uma ação padrão.Not all objects have a default action.

Description Description Description Description

Obtém uma cadeia de caracteres que descreve a aparência do objeto especificado.Gets a string that describes the visual appearance of the specified object. Nem todos os objetos têm uma descrição.Not all objects have a description.

Help Help Help Help

Obtém uma descrição do que o objeto faz ou como o objeto é usado.Gets a description of what the object does or how the object is used.

KeyboardShortcut KeyboardShortcut KeyboardShortcut KeyboardShortcut

Obtém a tecla de atalho ou a chave de acesso para o objeto acessível.Gets the shortcut key or access key for the accessible object.

Name Name Name Name

Obtém ou define o nome do objeto.Gets or sets the object name.

Parent Parent Parent Parent

Obtém o pai de um objeto acessível.Gets the parent of an accessible object.

Role Role Role Role

Obtém a função deste objeto acessível.Gets the role of this accessible object.

State State State State

Obtém o estado deste objeto acessível.Gets the state of this accessible object.

Value Value Value Value

Obtém ou define o valor de um objeto acessível.Gets or sets the value of an accessible object.

Métodos

CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type)

Cria um objeto que contém todas as informações relevantes necessárias para gerar um proxy usado para se comunicar com um objeto remoto.Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.

(Inherited from MarshalByRefObject)
DoDefaultAction() DoDefaultAction() DoDefaultAction() DoDefaultAction()

Executa a ação padrão associada a este objeto acessível.Performs the default action associated with this accessible object.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Determina se o objeto especificado é igual ao objeto atual.Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetChild(Int32) GetChild(Int32) GetChild(Int32) GetChild(Int32)

Recupera o filho acessível correspondente ao índice especificado.Retrieves the accessible child corresponding to the specified index.

GetChildCount() GetChildCount() GetChildCount() GetChildCount()

Recupera o número de filhos que pertencem a um objeto acessível.Retrieves the number of children belonging to an accessible object.

GetFocused() GetFocused() GetFocused() GetFocused()

Recupera o objeto que tem o foco do teclado.Retrieves the object that has the keyboard focus.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Serve como a função de hash padrão.Serves as the default hash function.

(Inherited from Object)
GetHelpTopic(String) GetHelpTopic(String) GetHelpTopic(String) GetHelpTopic(String)

Obtém um identificador para um identificador de tópico da Ajuda e o caminho para o arquivo de Ajuda associado a este objeto acessível.Gets an identifier for a Help topic identifier and the path to the Help file associated with this accessible object.

GetLifetimeService() GetLifetimeService() GetLifetimeService() GetLifetimeService()

Recupera o objeto de serviço de tempo de vida atual que controla a política de ciclo de vida para esta instância.Retrieves the current lifetime service object that controls the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
GetSelected() GetSelected() GetSelected() GetSelected()

Recupera o filho selecionado no momento.Retrieves the currently selected child.

GetType() GetType() GetType() GetType()

Obtém o Type da instância atual.Gets the Type of the current instance.

(Inherited from Object)
HitTest(Int32, Int32) HitTest(Int32, Int32) HitTest(Int32, Int32) HitTest(Int32, Int32)

Recupera o objeto filho nas coordenadas da tela especificadas.Retrieves the child object at the specified screen coordinates.

InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService()

Obtém um objeto de serviço de tempo de vida para controlar a política de tempo de vida para essa instância.Obtains a lifetime service object to control the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Cria uma cópia superficial do Object atual.Creates a shallow copy of the current Object.

(Inherited from Object)
MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean)

Cria uma cópia superficial do objeto MarshalByRefObject atual.Creates a shallow copy of the current MarshalByRefObject object.

(Inherited from MarshalByRefObject)
Navigate(AccessibleNavigation) Navigate(AccessibleNavigation) Navigate(AccessibleNavigation) Navigate(AccessibleNavigation)

Navega para outro objeto acessível.Navigates to another accessible object.

RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String) RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String) RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String) RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String)

Gera o evento de notificação de automação da interface do usuário.Raises the UI automation notification event.

RaiseLiveRegionChanged() RaiseLiveRegionChanged() RaiseLiveRegionChanged() RaiseLiveRegionChanged()

Gera o evento de automação da interface do usuário LiveRegionChanged.Raises the LiveRegionChanged UI automation event.

Select(AccessibleSelection) Select(AccessibleSelection) Select(AccessibleSelection) Select(AccessibleSelection)

Modifica a seleção ou move o foco do teclado do objeto acessível.Modifies the selection or moves the keyboard focus of the accessible object.

ToString() ToString() ToString() ToString()

Retorna uma cadeia de caracteres que representa o objeto atual.Returns a string that represents the current object.

(Inherited from Object)
UseStdAccessibleObjects(IntPtr) UseStdAccessibleObjects(IntPtr) UseStdAccessibleObjects(IntPtr) UseStdAccessibleObjects(IntPtr)

Associa um objeto a uma instância de um AccessibleObject com base no identificador do objeto.Associates an object with an instance of an AccessibleObject based on the handle of the object.

UseStdAccessibleObjects(IntPtr, Int32) UseStdAccessibleObjects(IntPtr, Int32) UseStdAccessibleObjects(IntPtr, Int32) UseStdAccessibleObjects(IntPtr, Int32)

Associa um objeto a uma instância de um AccessibleObject com base no identificador e na ID do objeto.Associates an object with an instance of an AccessibleObject based on the handle and the object id of the object.

Implantações explícitas de interface

IAccessible.accChildCount IAccessible.accChildCount IAccessible.accChildCount IAccessible.accChildCount

Obtém o número de interfaces filho que pertencem a este objeto.Gets the number of child interfaces that belong to this object. Para obter uma descrição desse membro, consulte accChildCount.For a description of this member, see accChildCount.

IAccessible.accDoDefaultAction(Object) IAccessible.accDoDefaultAction(Object) IAccessible.accDoDefaultAction(Object) IAccessible.accDoDefaultAction(Object)

Executa a ação padrão do objeto especificado.Performs the specified object's default action. Nem todos os objetos têm uma ação padrão.Not all objects have a default action. Para obter uma descrição desse membro, consulte accDoDefaultAction(Object).For a description of this member, see accDoDefaultAction(Object).

IAccessible.accFocus IAccessible.accFocus IAccessible.accFocus IAccessible.accFocus

Obtém o objeto que tem o foco do teclado.Gets the object that has the keyboard focus. Para obter uma descrição desse membro, consulte accFocus.For a description of this member, see accFocus.

IAccessible.accHitTest(Int32, Int32) IAccessible.accHitTest(Int32, Int32) IAccessible.accHitTest(Int32, Int32) IAccessible.accHitTest(Int32, Int32)

Obtém o objeto filho nas coordenadas da tela especificadas.Gets the child object at the specified screen coordinates. Para obter uma descrição desse membro, consulte accHitTest(Int32, Int32).For a description of this member, see accHitTest(Int32, Int32).

IAccessible.accLocation(Int32, Int32, Int32, Int32, Object) IAccessible.accLocation(Int32, Int32, Int32, Int32, Object) IAccessible.accLocation(Int32, Int32, Int32, Int32, Object) IAccessible.accLocation(Int32, Int32, Int32, Int32, Object)

Obtém o local da tela atual do objeto.Gets the object's current screen location. Para obter uma descrição desse membro, consulte accLocation(Int32, Int32, Int32, Int32, Object).For a description of this member, see accLocation(Int32, Int32, Int32, Int32, Object).

IAccessible.accNavigate(Int32, Object) IAccessible.accNavigate(Int32, Object) IAccessible.accNavigate(Int32, Object) IAccessible.accNavigate(Int32, Object)

Navega para um objeto acessível em relação ao objeto atual.Navigates to an accessible object relative to the current object. Para obter uma descrição desse membro, consulte accNavigate(Int32, Object).For a description of this member, see accNavigate(Int32, Object).

IAccessible.accParent IAccessible.accParent IAccessible.accParent IAccessible.accParent

Obtém o objeto acessível pai deste objeto.Gets the parent accessible object of this object. Para obter uma descrição desse membro, consulte accParent.For a description of this member, see accParent.

IAccessible.accSelect(Int32, Object) IAccessible.accSelect(Int32, Object) IAccessible.accSelect(Int32, Object) IAccessible.accSelect(Int32, Object)

Modifica a seleção ou move o foco do teclado do objeto acessível.Modifies the selection or moves the keyboard focus of the accessible object. Para obter uma descrição desse membro, consulte accSelect(Int32, Object).For a description of this member, see accSelect(Int32, Object).

IAccessible.accSelection IAccessible.accSelection IAccessible.accSelection IAccessible.accSelection

Obtém os objetos filho selecionados de um objeto acessível.Gets the selected child objects of an accessible object. Para obter uma descrição desse membro, consulte accSelection.For a description of this member, see accSelection.

IAccessible.get_accChild(Object) IAccessible.get_accChild(Object) IAccessible.get_accChild(Object) IAccessible.get_accChild(Object)

Recupera um objeto filho especificado.Retrieves a specified child object.

IAccessible.get_accDefaultAction(Object) IAccessible.get_accDefaultAction(Object) IAccessible.get_accDefaultAction(Object) IAccessible.get_accDefaultAction(Object)

Retorna uma cadeia de caracteres que indica a ação padrão do objeto especificado.Returns a string that indicates the specified object's default action.

IAccessible.get_accDescription(Object) IAccessible.get_accDescription(Object) IAccessible.get_accDescription(Object) IAccessible.get_accDescription(Object)

Retorna uma cadeia de caracteres que descreve a aparência visual do objeto acessível especificado.Returns a string that describes the visual appearance of the specified accessible object.

IAccessible.get_accHelp(Object) IAccessible.get_accHelp(Object) IAccessible.get_accHelp(Object) IAccessible.get_accHelp(Object)

Recupera o caminho completo do arquivo WinHelp associado ao objeto acessível especificado.Retrieves the full path of the WinHelp file that is associated with the specified accessible object.

IAccessible.get_accHelpTopic(String, Object) IAccessible.get_accHelpTopic(String, Object) IAccessible.get_accHelpTopic(String, Object) IAccessible.get_accHelpTopic(String, Object)

Recupera o caminho completo de um arquivo WinHelp associado ao objeto especificado em conjunto com o identificador de um tópico específico no arquivo.Retrieves the full path of a WinHelp file that is associated with the specified object along with the identifier of a specific topic in the file.

IAccessible.get_accKeyboardShortcut(Object) IAccessible.get_accKeyboardShortcut(Object) IAccessible.get_accKeyboardShortcut(Object) IAccessible.get_accKeyboardShortcut(Object)

Recupera o atalho de teclado ou a tecla de acesso do objeto especificado.Retrieves the specified object's keyboard shortcut or access key.

IAccessible.get_accName(Object) IAccessible.get_accName(Object) IAccessible.get_accName(Object) IAccessible.get_accName(Object)

Recupera o nome do objeto especificado.Retrieves the name of the specified object.

IAccessible.get_accRole(Object) IAccessible.get_accRole(Object) IAccessible.get_accRole(Object) IAccessible.get_accRole(Object)

Recupera informações que descrevem a função do objeto especificado.Retrieves information that describes the role of the specified object.

IAccessible.get_accState(Object) IAccessible.get_accState(Object) IAccessible.get_accState(Object) IAccessible.get_accState(Object)

Recupera o estado atual do objeto acessível especificado.Retrieves the current state of the specified accessible object.

IAccessible.get_accValue(Object) IAccessible.get_accValue(Object) IAccessible.get_accValue(Object) IAccessible.get_accValue(Object)

Recupera o valor do objeto acessível especificado.Retrieves the value of the specified accessible object. Nem todos os objetos possuem um valor.Not all objects have a value.

IAccessible.set_accName(Object, String) IAccessible.set_accName(Object, String) IAccessible.set_accName(Object, String) IAccessible.set_accName(Object, String)

Atribui um novo nome acessível ao objeto especificado.Assigns a new accessible name to the specified element.

IAccessible.set_accValue(Object, String) IAccessible.set_accValue(Object, String) IAccessible.set_accValue(Object, String) IAccessible.set_accValue(Object, String)

Atribui um novo valor ao elemento especificado.Assigns a new value to the specified element.

IReflect.GetField(String, BindingFlags) IReflect.GetField(String, BindingFlags) IReflect.GetField(String, BindingFlags) IReflect.GetField(String, BindingFlags)

Obtém o objeto FieldInfo correspondente ao campo e ao sinalizador de associação especificados.Gets the FieldInfo object corresponding to the specified field and binding flag. Para obter uma descrição desse membro, consulte GetField(String, BindingFlags).For a description of this member, see GetField(String, BindingFlags).

IReflect.GetFields(BindingFlags) IReflect.GetFields(BindingFlags) IReflect.GetFields(BindingFlags) IReflect.GetFields(BindingFlags)

Obtém uma matriz de objetos FieldInfo correspondentes a todos os campos da classe atual.Gets an array of FieldInfo objects corresponding to all fields of the current class. Para obter uma descrição desse membro, consulte GetFields(BindingFlags).For a description of this member, see GetFields(BindingFlags).

IReflect.GetMember(String, BindingFlags) IReflect.GetMember(String, BindingFlags) IReflect.GetMember(String, 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.Gets an array of MemberInfo objects corresponding to all public members or to all members that match a specified name. Para obter uma descrição desse membro, consulte GetMember(String, BindingFlags).For a description of this member, see GetMember(String, BindingFlags).

IReflect.GetMembers(BindingFlags) IReflect.GetMembers(BindingFlags) IReflect.GetMembers(BindingFlags) IReflect.GetMembers(BindingFlags)

Obtém uma matriz de objetos MemberInfo correspondentes a todos os membros públicos ou a todos os membros da classe atual.Gets an array of MemberInfo objects corresponding either to all public members or to all members of the current class. Para obter uma descrição desse membro, consulte GetMembers(BindingFlags).For a description of this member, see GetMembers(BindingFlags).

IReflect.GetMethod(String, BindingFlags) IReflect.GetMethod(String, BindingFlags) IReflect.GetMethod(String, BindingFlags) IReflect.GetMethod(String, BindingFlags)

Obtém um objeto MethodInfo que corresponde a um método especificado nas restrições de pesquisa especificadas.Gets a MethodInfo object corresponding to a specified method under specified search constraints. Para obter uma descrição desse membro, consulte GetMethod(String, BindingFlags).For a description of this member, see GetMethod(String, BindingFlags).

IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]) IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]) IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]) IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[])

Obtém um objeto MethodInfo correspondente a um método especificado, usando uma matriz de Tipo para escolher entre métodos sobrecarregados.Gets a MethodInfo object corresponding to a specified method, using a Type array to choose from among overloaded methods. Para obter uma descrição desse membro, consulte GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]).For a description of this member, see GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]).

IReflect.GetMethods(BindingFlags) IReflect.GetMethods(BindingFlags) IReflect.GetMethods(BindingFlags) IReflect.GetMethods(BindingFlags)

Obtém uma matriz de objetos MethodInfo com todos os métodos públicos ou todos os métodos da classe atual.Gets an array of MethodInfo objects with all public methods or all methods of the current class. Para obter uma descrição desse membro, consulte GetMethods(BindingFlags).For a description of this member, see GetMethods(BindingFlags).

IReflect.GetProperties(BindingFlags) IReflect.GetProperties(BindingFlags) IReflect.GetProperties(BindingFlags) IReflect.GetProperties(BindingFlags)

Obtém uma matriz de objetos PropertyInfo que correspondem a todas as propriedades públicas ou a todas as propriedades da classe atual.Gets an array of PropertyInfo objects corresponding to all public properties or to all properties of the current class. Para obter uma descrição desse membro, consulte GetProperties(BindingFlags).For a description of this member, see GetProperties(BindingFlags).

IReflect.GetProperty(String, BindingFlags) IReflect.GetProperty(String, BindingFlags) IReflect.GetProperty(String, BindingFlags) IReflect.GetProperty(String, BindingFlags)

Obtém um objeto PropertyInfo que corresponde a uma propriedade especificada nas restrições de pesquisa especificadas.Gets a PropertyInfo object corresponding to a specified property under specified search constraints. Para obter uma descrição desse membro, consulte GetProperty(String, BindingFlags).For a description of this member, see GetProperty(String, BindingFlags).

IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]) IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]) IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]) IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])

Obtém um objeto PropertyInfo que corresponde a uma propriedade especificada com as restrições de pesquisa especificadas.Gets a PropertyInfo object corresponding to a specified property with specified search constraints. Para obter uma descrição desse membro, consulte GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]).For a description of this member, see GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]).

IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]) IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]) IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]) IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[])

Invoca um membro especificado.Invokes a specified member. Para obter uma descrição desse membro, consulte InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]).For a description of this member, see InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]).

IReflect.UnderlyingSystemType IReflect.UnderlyingSystemType IReflect.UnderlyingSystemType IReflect.UnderlyingSystemType

Obtém o tipo subjacente que representa o objeto IReflect.Gets the underlying type that represents the IReflect object. Para obter uma descrição desse membro, consulte UnderlyingSystemType.For a description of this member, see UnderlyingSystemType.

Aplica-se a