ButtonRenderer Klas

Definitie

public ref class ButtonRenderer sealed

public ref class ButtonRenderer abstract sealed

public sealed class ButtonRenderer

public static class ButtonRenderer

type ButtonRenderer = class

Public NotInheritable Class ButtonRenderer

Public Class ButtonRenderer

Overname

Object

ButtonRenderer

Voorbeelden

In het volgende codevoorbeeld ziet u hoe u een aangepast besturingselement maakt dat gebruikmaakt van de DrawButton methode om een knop te tekenen. Wanneer op de knop wordt geklikt, tekent het besturingselement een kleinere knop binnen de grenzen van de oorspronkelijke knop en gebruikt het besturingselement de DrawParentBackground methode om de rest van de oorspronkelijke knop te schilderen.

#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 ButtonRendererSample
{
    public ref class CustomButton : public Control
    {
    private:
        Rectangle clickRectangleValue;

    private:
        PushButtonState state;

    public:
        CustomButton()
        {
            __super::Control();
            this->Size = System::Drawing::Size(100, 40);
            this->Location = Point(50, 50);
            this->Font = SystemFonts::IconTitleFont;
            this->Text = "Click here";
            clickRectangleValue = Rectangle();
            state = PushButtonState::Normal;
        }

        // Define the bounds of the smaller pressed button.
    public:
        property Rectangle ClickRectangle
        {
            Rectangle get()
            {
                clickRectangleValue.X = ClientRectangle.X +
                    (int)(.2 * ClientRectangle.Width);
                clickRectangleValue.Y = ClientRectangle.Y +
                    (int)(.2 * ClientRectangle.Height);
                clickRectangleValue.Width = ClientRectangle.Width -
                    (int)(.4 * ClientRectangle.Width);
                clickRectangleValue.Height = ClientRectangle.Height -
                    (int)(.4 * ClientRectangle.Height);

                return clickRectangleValue;
            }
        }

        // Draw the large or small button, depending on the current state.
    protected:
        virtual void OnPaint(PaintEventArgs^ e) override
        {
            __super::OnPaint(e);

            // Draw the smaller pressed button image
            if (state == PushButtonState::Pressed)
            {
                // Set the background color to the parent if visual styles
                // are disabled, because DrawParentBackground will only paint
                // over the control background if visual styles are enabled.
                if (Application::RenderWithVisualStyles)
                {
                    this->BackColor = Color::Azure;
                }
                else
                {
                    this->BackColor = this->Parent->BackColor;
                }


                // If you comment out the call to DrawParentBackground,
                // the background of the control will still be visible
                // outside the pressed button, if visual styles are enabled.
                ButtonRenderer::DrawParentBackground(e->Graphics,
                    ClientRectangle, this);
                ButtonRenderer::DrawButton(e->Graphics, ClickRectangle,
                    this->Text, this->Font, true, state);
            }

            // Draw the bigger unpressed button image.
            else
            {
                ButtonRenderer::DrawButton(e->Graphics, ClientRectangle,
                    this->Text, this->Font, false, state);
            }
        }

        // Draw the smaller pressed button image.
    protected:
        virtual void OnMouseDown(MouseEventArgs^ e) override
        {
            __super::OnMouseDown(e);
            this->Text = "Clicked!";
            state = PushButtonState::Pressed;
            Invalidate();
        }

        // Draw the button in the hot state.
    protected:
        virtual void OnMouseEnter(EventArgs^ e) override
        {
            __super::OnMouseEnter(e);
            this->Text = "Click here";
            state = PushButtonState::Hot;
            Invalidate();
        }

        // Draw the button in the unpressed state.
    protected:
        virtual void OnMouseLeave(EventArgs^ e) override
        {
            __super::OnMouseLeave(e);
            this->Text = "Click here";
            state = PushButtonState::Normal;
            Invalidate();
        }

        // Draw the button hot if the mouse is released on the button.
    protected:
        virtual void OnMouseUp(MouseEventArgs^ e) override
        {
            __super::OnMouseUp(e);
            OnMouseEnter(e);
        }

        // Detect when the cursor leaves the button area while
        // it is pressed.
    protected:
        virtual void OnMouseMove(MouseEventArgs^ e) override
        {
            __super::OnMouseMove(e);

            // Detect when the left mouse button is down and
            // the cursor has left the pressed button area.
            if ((e->Button & ::MouseButtons::Left) == ::MouseButtons::Left &&
                !ClientRectangle.Contains(e->Location) &&
                state == PushButtonState::Pressed)
            {
                OnMouseLeave(e);
            }
        }
    };

    ref class Form1 : public Form
    {
    public:
        Form1()
        {
            __super::Form();
            CustomButton^ Button1 = gcnew CustomButton();
            Controls->Add(Button1);

            if (Application::RenderWithVisualStyles)
            {
                this->Text = "Visual Styles Enabled";
            }
            else
            {
                this->Text = "Visual Styles Disabled";
            }
        }
    };   
}

using namespace ButtonRendererSample;

[STAThread]
int main()
{ 
    // If you do not call EnableVisualStyles below, then
    // ButtonRenderer automatically detects this and draws
    // the button without visual styles.
    Application::EnableVisualStyles();
    Application::Run(gcnew Form1());
}

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

namespace ButtonRendererSample
{
    class Form1 : Form
    {
        public Form1()
            : base()
        {
            CustomButton Button1 = new CustomButton();
            Controls.Add(Button1);

            if (Application.RenderWithVisualStyles)
                this.Text = "Visual Styles Enabled";
            else
                this.Text = "Visual Styles Disabled";
        }

        [STAThread]
        static void Main()
        {
            // If you do not call EnableVisualStyles below, then   
            // ButtonRenderer automatically detects this and draws
            // the button without visual styles.
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }
    }

    public class CustomButton : Control
    {
        private Rectangle clickRectangleValue = new Rectangle();
        private PushButtonState state = PushButtonState.Normal;

        public CustomButton()
            : base()
        {
            this.Size = new Size(100, 40);
            this.Location = new Point(50, 50);
            this.Font = SystemFonts.IconTitleFont;
            this.Text = "Click here";
        }

        // Define the bounds of the smaller pressed button.
        public Rectangle ClickRectangle
        {
            get
            {
                clickRectangleValue.X = ClientRectangle.X +
                    (int)(.2 * ClientRectangle.Width);
                clickRectangleValue.Y = ClientRectangle.Y +
                    (int)(.2 * ClientRectangle.Height);
                clickRectangleValue.Width = ClientRectangle.Width -
                    (int)(.4 * ClientRectangle.Width);
                clickRectangleValue.Height = ClientRectangle.Height -
                    (int)(.4 * ClientRectangle.Height);

                return clickRectangleValue;
            }
        }

        // Draw the large or small button, depending on the current state.
        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);

            // Draw the smaller pressed button image
            if (state == PushButtonState.Pressed)
            {
                // Set the background color to the parent if visual styles  
                // are disabled, because DrawParentBackground will only paint  
                // over the control background if visual styles are enabled.
                this.BackColor = Application.RenderWithVisualStyles ?
                    Color.Azure : this.Parent.BackColor;

                // If you comment out the call to DrawParentBackground, 
                // the background of the control will still be visible 
                // outside the pressed button, if visual styles are enabled.
                ButtonRenderer.DrawParentBackground(e.Graphics,
                    ClientRectangle, this);
                ButtonRenderer.DrawButton(e.Graphics, ClickRectangle,
                    this.Text, this.Font, true, state);
            }

            // Draw the bigger unpressed button image.
            else
            {
                ButtonRenderer.DrawButton(e.Graphics, ClientRectangle,
                    this.Text, this.Font, false, state);
            }
        }

        // Draw the smaller pressed button image.
        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);
            this.Text = "Clicked!";
            state = PushButtonState.Pressed;
            Invalidate();
        }

        // Draw the button in the hot state. 
        protected override void OnMouseEnter(EventArgs e)
        {
            base.OnMouseEnter(e);
            this.Text = "Click here";
            state = PushButtonState.Hot;
            Invalidate();
        }

        // Draw the button in the unpressed state.
        protected override void OnMouseLeave(EventArgs e)
        {
            base.OnMouseLeave(e);
            this.Text = "Click here";
            state = PushButtonState.Normal;
            Invalidate();
        }

        // Draw the button hot if the mouse is released on the button. 
        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);
            OnMouseEnter(e);
        }

        // Detect when the cursor leaves the button area while 
        // it is pressed.
        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e);

            // Detect when the left mouse button is down and   
            // the cursor has left the pressed button area. 
            if ((e.Button & MouseButtons.Left) == MouseButtons.Left &&
                !ClientRectangle.Contains(e.Location) &&
                state == PushButtonState.Pressed)
            {
                OnMouseLeave(e);
            }
        }
    }
}

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

Namespace ButtonRendererSample
    Class Form1
        Inherits Form

        Public Sub New()
            Dim Button1 As New CustomButton()
            Controls.Add(Button1)

            If Application.RenderWithVisualStyles Then
                Me.Text = "Visual Styles Enabled"
            Else
                Me.Text = "Visual Styles Disabled"
            End If
        End Sub

        <STAThread()> _
        Shared Sub Main()
            ' If you do not call EnableVisualStyles below, then  
            ' ButtonRenderer automatically detects this and draws
            ' the button without visual styles.
            Application.EnableVisualStyles()
            Application.Run(New Form1())
        End Sub
    End Class

    Public Class CustomButton
        Inherits Control

        Private clickRectangleValue As New Rectangle()
        Private state As PushButtonState = PushButtonState.Normal

        Public Sub New()
            With Me
                Size = New Size(100, 40)
                Location = New Point(50, 50)
                Font = SystemFonts.IconTitleFont
                Text = "Click here"
            End With
        End Sub

        ' Define the bounds of the smaller pressed button.
        Public ReadOnly Property ClickRectangle() As Rectangle
            Get
                With clickRectangleValue
                    .X = Me.ClientRectangle.X + CInt(0.2 * _
                        Me.ClientRectangle.Width)
                    .Y = Me.ClientRectangle.Y + CInt(0.2 * _
                        Me.ClientRectangle.Height)
                    .Width = Me.ClientRectangle.Width - _
                        CInt(0.4 * Me.ClientRectangle.Width)
                    .Height = Me.ClientRectangle.Height - _
                        CInt(0.4 * Me.ClientRectangle.Height)
                End With
                Return clickRectangleValue
            End Get
        End Property

        ' Draw the large or small button, depending on the current state.
        Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
            MyBase.OnPaint(e)

            ' Draw the smaller pressed button image.
            If state = PushButtonState.Pressed Then
                ' Set the background color to the parent if visual styles  
                ' are disabled, because DrawParentBackground will only paint  
                ' over the control background if visual styles are enabled.
                If Application.RenderWithVisualStyles Then
                    Me.BackColor = Color.Azure
                Else
                    Me.BackColor = Me.Parent.BackColor
                End If

                ' If you comment out the call to DrawParentBackground,   
                ' the background of the control will still be visible 
                ' outside the pressed button, if visual styles are enabled.
                ButtonRenderer.DrawParentBackground(e.Graphics, _
                    Me.ClientRectangle, Me)
                ButtonRenderer.DrawButton(e.Graphics, ClickRectangle, _
                    Me.Text, Me.Font, True, state)

            ' Draw the bigger unpressed button image.
            Else
                ButtonRenderer.DrawButton(e.Graphics, Me.ClientRectangle, _
                    Me.Text, Me.Font, False, state)
            End If
        End Sub

        ' Draw the smaller pressed button image.
        Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs)
            MyBase.OnMouseDown(e)
            With Me
                .Text = "Clicked!"
                .state = PushButtonState.Pressed
            End With
            Invalidate()
        End Sub

        ' Draw the button in the hot state. 
        Protected Overrides Sub OnMouseEnter(ByVal e As EventArgs)
            MyBase.OnMouseEnter(e)
            With Me
                .Text = "Click here"
                .state = PushButtonState.Hot
            End With
            Invalidate()
        End Sub

        ' Draw the button in the unpressed state.
        Protected Overrides Sub OnMouseLeave(ByVal e As EventArgs)
            MyBase.OnMouseLeave(e)
            With Me
                .Text = "Click here"
                .state = PushButtonState.Normal
            End With
            Invalidate()
        End Sub

        ' Draw the button hot if the mouse is released on the button.
        Protected Overrides Sub OnMouseUp(ByVal e As MouseEventArgs)
            MyBase.OnMouseUp(e)
            OnMouseEnter(e)
        End Sub

        ' Detect when the cursor leaves the button area while it 
        ' is pressed.
        Protected Overrides Sub OnMouseMove(ByVal e As MouseEventArgs)
            MyBase.OnMouseMove(e)

            ' Detect when the left mouse button is down and   
            ' the cursor has left the pressed button area. 
            If (e.Button And MouseButtons.Left) = MouseButtons.Left And Not _
                Me.ClientRectangle.Contains(e.Location) And _
                state = PushButtonState.Pressed Then
                OnMouseLeave(e)
            End If
        End Sub

    End Class
End Namespace

Opmerkingen

De ButtonRenderer klasse biedt een set static methoden die kunnen worden gebruikt om een knop besturingselement weer te geven. Het weergeven van een besturingselement verwijst naar het tekenen van de gebruikersinterface van een besturingselement. Als u een knop wilt tekenen, gebruikt u een van de DrawButton methoden. Deze methoden bieden verschillende opties, zoals tekentekst of een afbeelding op de knop.

Als visuele stijlen zijn ingeschakeld in het besturingssysteem en visuele stijlen worden toegepast op de huidige toepassing, DrawButton tekent u de knop met de huidige visuele stijl. Anders tekent DrawButton de knop met de klassieke stijl Windows. Dit is handig als u een aangepast besturingselement tekent dat automatisch overeenkomt met de huidige instelling van de visuele stijl van het besturingssysteem.

Deze klasse verpakt de functionaliteit van een System.Windows.Forms.VisualStyles.VisualStyleRenderer die is ingesteld op een van de elementen die worden weergegeven door de klasse System.Windows.Forms.VisualStyles.VisualStyleElement.Button.PushButton. Zie Weergavebesturingselementen met visuele stijlen voor meer informatie.

Zie ook

• EnableVisualStyles()
• RenderWithVisualStyles
• VisualStyleRenderer
• VisualStyleElement