ButtonRenderer 類別

定義

public ref class ButtonRenderer sealed

public sealed class ButtonRenderer

type ButtonRenderer = class

Public NotInheritable Class ButtonRenderer

繼承

Object

ButtonRenderer

範例

以下程式碼範例示範如何建立一個自訂控制項，利用該 DrawButton 方法繪製按鈕。 當按鈕被點擊時，控制鍵會在原按鈕的範圍內畫出一個較小的按鈕，並用此 DrawParentBackground 方法將原按鈕的其餘部分塗上。

#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

備註

這個 ButtonRenderer 類別提供了一組 static 可以用來渲染按鈕控制的方法。 呈現控制項是指繪製控制項的使用者介面。 要畫按鈕，請使用其中一種 DrawButton 方法。 這些方法提供多種選項，例如在按鈕上繪製文字或圖像。

如果作業系統啟用了視覺樣式，且將視覺樣式套用到目前應用程式， DrawButton 將會繪製出該按鈕。 否則，DrawButton 會用經典的 Windows 風格抽到按鈕。 如果你要繪製自訂控制項，該控制項應該會自動與作業系統的視覺風格設定相匹配，這很有用。

此類別將 A 的功能 System.Windows.Forms.VisualStyles.VisualStyleRenderer 包裝成該類別所暴露 System.Windows.Forms.VisualStyles.VisualStyleElement.Button.PushButton 的元素之一。 欲了解更多資訊，請參閱 「以視覺樣式渲染控制」。

另請參閱

• EnableVisualStyles()
• RenderWithVisualStyles
• VisualStyleRenderer
• VisualStyleElement