ComboBoxRenderer Classe

Définition

Espace de noms:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Fournit des méthodes utilisées pour restituer un contrôle zone de liste déroulante avec des styles visuels. Cette classe ne peut pas être héritée.

public ref class ComboBoxRenderer abstract sealed

public static class ComboBoxRenderer

type ComboBoxRenderer = class

Public Class ComboBoxRenderer

Héritage

Object

ComboBoxRenderer

Exemples

L’exemple de code suivant montre comment créer un contrôle personnalisé qui utilise les DrawTextBox méthodes et DrawDropDownButton pour dessiner une zone de liste modifiable qui répond aux clics de souris.

#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::VisualStyles;

namespace ComboBoxRendererSample
{
    ref class CustomComboBox: public Control
    {
    private:
        System::Drawing::Size arrowSize;
        Rectangle arrowRectangle;
        Rectangle topTextBoxRectangle;
        Rectangle bottomTextBoxRectangle;
        ComboBoxState textBoxState;
        ComboBoxState arrowState;
        String^ bottomText;
        bool isActivated;
        int minHeight;
        int minWidth;

    public:
        CustomComboBox() : Control()

          {
              minHeight = 38;
              minWidth = 40; 
              this->Location = Point(10, 10);
              this->Size = System::Drawing::Size(140, 38);
              this->Font = SystemFonts::IconTitleFont;
              this->Text = "Click the button";
              textBoxState = ComboBoxState::Normal;
              bottomText = "Using ComboBoxRenderer";
              arrowState = ComboBoxState::Normal;

              // Initialize the rectangles to look like the standard combo
              // box control.
              arrowSize = System::Drawing::Size(18, 20);
              arrowRectangle = Rectangle(ClientRectangle.X +
                  ClientRectangle.Width - arrowSize.Width - 1,
                  ClientRectangle.Y + 1,
                  arrowSize.Width,
                  arrowSize.Height);
              topTextBoxRectangle = Rectangle(ClientRectangle.X,
                  ClientRectangle.Y,
                  ClientRectangle.Width,
                  arrowSize.Height + 2);
              bottomTextBoxRectangle = Rectangle(ClientRectangle.X,
                  ClientRectangle.Y + topTextBoxRectangle.Height,
                  ClientRectangle.Width,
                  topTextBoxRectangle.Height - 6);
          }

          // Draw the combo box in the current state.
    protected:
        virtual void OnPaint(PaintEventArgs^ e) override 
        {
            Control::OnPaint(e);

            if (!ComboBoxRenderer::IsSupported)
            {
                this->Parent->Text = "Visual Styles Disabled";
                return;
            }

            this->Parent->Text = "CustomComboBox Enabled";

            // Always draw the main text box and drop down arrow in their
            // current states
            ComboBoxRenderer::DrawTextBox(e->Graphics, topTextBoxRectangle,
                this->Text, this->Font, textBoxState);
            ComboBoxRenderer::DrawDropDownButton(e->Graphics, arrowRectangle,
                arrowState);

            // Only draw the bottom text box if the arrow has been clicked
            if (isActivated)
            {
                ComboBoxRenderer::DrawTextBox(e->Graphics,
                    bottomTextBoxRectangle, bottomText, this->Font,
                    textBoxState);
            }
        }

    protected:
        virtual void OnMouseDown(MouseEventArgs^ e) override 
        {
            Control::OnMouseDown(e);

            // Check whether the user clicked the arrow.
            if (arrowRectangle.Contains(e->Location) &&
                ComboBoxRenderer::IsSupported)
            {
                // Draw the arrow in the pressed state.
                arrowState = ComboBoxState::Pressed;

                // The user has activated the combo box.
                if (!isActivated)
                {
                    this->Text = "Clicked!";
                    textBoxState = ComboBoxState::Pressed;
                    isActivated = true;
                }

                // The user has deactivated the combo box.
                else
                {
                    this->Text = "Click here";
                    textBoxState = ComboBoxState::Normal;
                    isActivated = false;
                }

                // Redraw the control.
                Invalidate();
            }
        }

    protected:
        virtual void OnMouseUp(MouseEventArgs^ e) override 
        {
            Control::OnMouseUp(e);

            if (arrowRectangle.Contains(e->Location) &&
                ComboBoxRenderer::IsSupported)
            {
                arrowState = ComboBoxState::Normal;
                Invalidate();
            }
        }
    };

    ref class Form1 : public Form
    {
    public:
        Form1() : Form()
        {
            this->Size = System::Drawing::Size(300, 300);
            CustomComboBox^ ComboBox1 = gcnew CustomComboBox();
            Controls->Add(ComboBox1);
        }

    };

}

[STAThread]
int main()
{
    // The call to EnableVisualStyles below does not affect
    // whether ComboBoxRenderer.IsSupported is true; as long as visual
    // styles are enabled by the operating system, IsSupported is true.
    Application::EnableVisualStyles();
    Application::Run(gcnew ComboBoxRendererSample::Form1());

}

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.VisualStyles;

namespace ComboBoxRendererSample
{
    class Form1 : Form
    {
        public Form1()
            : base()
        {
            this.Size = new Size(300, 300);
            CustomComboBox ComboBox1 = new CustomComboBox();
            Controls.Add(ComboBox1);
        }

        [STAThread]
        static void Main()
        {
            // The call to EnableVisualStyles below does not affect
            // whether ComboBoxRenderer.IsSupported is true; as long as visual
            // styles are enabled by the operating system, IsSupported is true.
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }
    }

    public class CustomComboBox : Control
    {
        private Size arrowSize;
        private Rectangle arrowRectangle;
        private Rectangle topTextBoxRectangle;
        private Rectangle bottomTextBoxRectangle;
        private ComboBoxState textBoxState = ComboBoxState.Normal;
        private ComboBoxState arrowState = ComboBoxState.Normal;
        private String bottomText = "Using ComboBoxRenderer";
        private bool isActivated = false;
        private const int minHeight = 38;
        private const int minWidth = 40;

        public CustomComboBox()
            : base()
        {
            this.Location = new Point(10, 10);
            this.Size = new Size(140, 38);
            this.Font = SystemFonts.IconTitleFont;
            this.Text = "Click the button";

            // Initialize the rectangles to look like the standard combo 
            // box control.
            arrowSize = new Size(18, 20);
            arrowRectangle = new Rectangle(ClientRectangle.X +
                ClientRectangle.Width - arrowSize.Width - 1,
                ClientRectangle.Y + 1,
                arrowSize.Width,
                arrowSize.Height);
            topTextBoxRectangle = new Rectangle(ClientRectangle.X,
                ClientRectangle.Y,
                ClientRectangle.Width,
                arrowSize.Height + 2);
            bottomTextBoxRectangle = new Rectangle(ClientRectangle.X,
                ClientRectangle.Y + topTextBoxRectangle.Height,
                ClientRectangle.Width,
                topTextBoxRectangle.Height - 6);
        }

        // Draw the combo box in the current state.
        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);

            if (!ComboBoxRenderer.IsSupported)
            {
                this.Parent.Text = "Visual Styles Disabled";
                return;
            }

            this.Parent.Text = "CustomComboBox Enabled";

            // Always draw the main text box and drop down arrow in their 
            // current states
            ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle,
                this.Text, this.Font, textBoxState);
            ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle,
                arrowState);

            // Only draw the bottom text box if the arrow has been clicked
            if (isActivated)
            {
                ComboBoxRenderer.DrawTextBox(e.Graphics,
                    bottomTextBoxRectangle, bottomText, this.Font,
                    textBoxState);
            }
        }

        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);

            // Check whether the user clicked the arrow.
            if (arrowRectangle.Contains(e.Location) &&
                ComboBoxRenderer.IsSupported)
            {
                // Draw the arrow in the pressed state.
                arrowState = ComboBoxState.Pressed;

                // The user has activated the combo box.
                if (!isActivated)
                {
                    this.Text = "Clicked!";
                    textBoxState = ComboBoxState.Pressed;
                    isActivated = true;
                }

                // The user has deactivated the combo box.
                else
                {
                    this.Text = "Click here";
                    textBoxState = ComboBoxState.Normal;
                    isActivated = false;
                }

                // Redraw the control.
                Invalidate();
            }
        }

        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);

            if (arrowRectangle.Contains(e.Location) &&
                ComboBoxRenderer.IsSupported)
            {
                arrowState = ComboBoxState.Normal;
                Invalidate();
            }
        }
    }
}

Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles

Namespace ComboBoxRendererSample
    Class Form1
        Inherits Form

        Public Sub New()
            Me.Size = New Size(300, 300)
            Dim ComboBox1 As New CustomComboBox()
            Controls.Add(ComboBox1)
        End Sub

        <STAThread()> _
        Shared Sub Main()
            ' The call to EnableVisualStyles below does not affect
            ' whether ComboBoxRenderer.IsSupported is true; as long as visual
            ' styles are enabled by the operating system, IsSupported is true.
            Application.EnableVisualStyles()
            Application.Run(New Form1())
        End Sub
    End Class

    Public Class CustomComboBox
        Inherits Control

        Private arrowSize As Size
        Private arrowRectangle As Rectangle
        Private topTextBoxRectangle As Rectangle
        Private bottomTextBoxRectangle As Rectangle
        Private textBoxState As ComboBoxState = ComboBoxState.Normal
        Private arrowState As ComboBoxState = ComboBoxState.Normal
        Private bottomText As String = "Using ComboBoxRenderer"
        Private isActivated As Boolean = False
        Private minHeight As Integer = 38
        Private minWidth As Integer = 40

        Public Sub New()
            Me.Location = New Point(10, 10)
            Me.Size = New Size(140, 38)
            Me.Font = SystemFonts.IconTitleFont
            Me.Text = "Click the button"

            ' Initialize the rectangles to look like the standard combo 
            ' box control.
            arrowSize = New Size(18, 20)
            arrowRectangle = New Rectangle(Me.ClientRectangle.X + _
                Me.ClientRectangle.Width - arrowSize.Width - 1, _
                Me.ClientRectangle.Y + 1, arrowSize.Width, _
                arrowSize.Height)
            topTextBoxRectangle = New Rectangle(Me.ClientRectangle.X, _
                Me.ClientRectangle.Y, Me.ClientRectangle.Width, _
                arrowSize.Height + 2)
            bottomTextBoxRectangle = New Rectangle(Me.ClientRectangle.X, _
                Me.ClientRectangle.Y + topTextBoxRectangle.Height, _
                Me.ClientRectangle.Width, topTextBoxRectangle.Height - 6)
        End Sub

        ' Draw the combo box in the current state.
        Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
            MyBase.OnPaint(e)

            If Not ComboBoxRenderer.IsSupported Then
                Me.Parent.Text = "Visual Styles	Disabled"
                Return
            End If

            Me.Parent.Text = "CustomComboBox Enabled"

            ' Always draw the main text box and drop down arrow in their 
            ' current states.
            ComboBoxRenderer.DrawTextBox(e.Graphics, topTextBoxRectangle, _
                Me.Text, Me.Font, textBoxState)
            ComboBoxRenderer.DrawDropDownButton(e.Graphics, arrowRectangle, _
                arrowState)

            ' Only draw the bottom text box if the arrow has been clicked.
            If isActivated Then
                ComboBoxRenderer.DrawTextBox(e.Graphics, _
                    bottomTextBoxRectangle, bottomText, Me.Font, textBoxState)
            End If
        End Sub

        Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs)
            MyBase.OnMouseDown(e)

            ' Check whether the user clicked the arrow.
            If arrowRectangle.Contains(e.Location) And _
                ComboBoxRenderer.IsSupported Then

                ' Draw the arrow in the pressed state.
                arrowState = ComboBoxState.Pressed

                ' The user has activated the combo box.
                If Not isActivated Then
                    Me.Text = "Clicked!"
                    textBoxState = ComboBoxState.Pressed
                    isActivated = True

                ' The user has deactivated the combo box.
                Else
                    Me.Text = "Click here"
                    textBoxState = ComboBoxState.Normal
                    isActivated = False
                End If

                ' Redraw the control.
                Invalidate()
            End If
        End Sub

        Protected Overrides Sub OnMouseUp(ByVal e As MouseEventArgs)
            MyBase.OnMouseUp(e)
            If arrowRectangle.Contains(e.Location) And _
                ComboBoxRenderer.IsSupported Then
                arrowState = ComboBoxState.Normal
                Invalidate()
            End If
        End Sub

    End Class
End Namespace

Remarques

La ComboBoxRenderer classe fournit un ensemble de static méthodes qui peuvent être utilisées pour afficher un contrôle de zone de liste modifiable avec le style visuel actuel du système d’exploitation. Le rendu d’un contrôle fait référence au dessin de l’interface utilisateur d’un contrôle. Cela est utile si vous dessinez un contrôle personnalisé qui doit avoir l’apparence du style visuel actuel. Pour dessiner une zone de liste déroulante, utilisez la DrawTextBox méthode pour dessiner la zone de texte et la DrawDropDownButton méthode pour dessiner la flèche déroulante.

Si les styles visuels sont activés dans le système d’exploitation et que les styles visuels sont appliqués à la zone cliente des fenêtres d’application, DrawTextBox ils DrawDropDownButton dessinent la zone de liste déroulante avec le style visuel actuel. Sinon, ces méthodes lèvent un InvalidOperationException. Pour déterminer si les membres de cette classe peuvent être utilisés, vous pouvez vérifier la valeur de la IsSupported propriété .

Cette classe encapsule les fonctionnalités d’un System.Windows.Forms.VisualStyles.VisualStyleRenderer qui est défini sur l’un des éléments exposés par les System.Windows.Forms.VisualStyles.VisualStyleElement.ComboBox.DropDownButton classes et System.Windows.Forms.VisualStyles.VisualStyleElement.TextBox.TextEdit . Pour plus d’informations, consultez Rendu des contrôles avec les styles visuels.

Propriétés

IsSupported

Obtient une valeur indiquant si la classe ComboBoxRenderer peut être utilisée pour dessiner une zone de liste déroulante avec des styles visuels.

Méthodes

DrawDropDownButton(Graphics, Rectangle, ComboBoxState)	Dessine une flèche de déroulement avec le style visuel actuel du système d'exploitation.
DrawTextBox(Graphics, Rectangle, ComboBoxState)	Dessine une zone de texte dans l'état et les limites spécifiés.
DrawTextBox(Graphics, Rectangle, String, Font, ComboBoxState)	Dessine une zone de texte dans l'état et les limites spécifiés, avec le texte spécifié.
DrawTextBox(Graphics, Rectangle, String, Font, Rectangle, ComboBoxState)	Dessine une zone de texte dans l'état et les limites spécifiés, avec le texte et les limites de texte spécifiés.
DrawTextBox(Graphics, Rectangle, String, Font, Rectangle, TextFormatFlags, ComboBoxState)	Dessine une zone de texte dans l'état et les limites spécifiés, avec le texte, la mise en forme du texte et les limites de texte spécifiés.
DrawTextBox(Graphics, Rectangle, String, Font, TextFormatFlags, ComboBoxState)	Dessine une zone de texte dans l'état et les limites spécifiés, avec le texte et la mise en forme du texte spécifiés.

Voir aussi

• VisualStyleRenderer
• VisualStyleElement