CheckBoxRenderer Class
Assembly: System.Windows.Forms (in system.windows.forms.dll)
The CheckBoxRenderer class provides a set of static methods that can be used to render a check box control. Rendering a control refers to drawing the user interface of a control. To draw a check box, use one of the DrawCheckBox methods. These methods provide a variety of options, such as drawing text or an image with the check box.
If visual styles are enabled in the operating system and visual styles are applied to the current application, DrawCheckBox will draw the check box with the current visual style. Otherwise, DrawCheckBox will draw the check box with the classic Windows style. This is useful if you are drawing a custom control that should automatically match the current visual style setting of the operating system.
This class wraps the functionality of a System.Windows.Forms.VisualStyles.VisualStyleRenderer that is set to one of the elements exposed by the System.Windows.Forms.VisualStyles.VisualStyleElement.Button.CheckBox class. For more information, see Rendering Controls with Visual Styles.
Windows XP Home Edition, Windows XP Professional x64 Edition, Windows Server 2003 Platform Note: Visual styles are supported only on these platforms.
The following code example demonstrates how to write a custom control that uses the DrawCheckBox method to draw a check box that responds to mouse clicks.
Imports System Imports System.Drawing Imports System.Windows.Forms Imports System.Windows.Forms.VisualStyles Namespace CheckBoxRendererSample Class Form1 Inherits Form Public Sub New() Dim CheckBox1 As New CustomCheckBox() Controls.Add(CheckBox1) 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 ' CheckBoxRenderer.DrawCheckBox automatically detects ' this and draws the check box without visual styles. Application.EnableVisualStyles() Application.Run(New Form1()) End Sub End Class Public Class CustomCheckBox Inherits Control Private textRectangleValue As New Rectangle() Private clickedLocationValue As New Point() Private clicked As Boolean = False Private state As CheckBoxState = CheckBoxState.UncheckedNormal Public Sub New() With Me .Location = New Point(50, 50) .Size = New Size(100, 20) .Text = "Click here" .Font = SystemFonts.IconTitleFont End With End Sub ' Calculate the text bounds, exluding the check box. Public ReadOnly Property TextRectangle() As Rectangle Get Using g As Graphics = Me.CreateGraphics() With textRectangleValue .X = Me.ClientRectangle.X + _ CheckBoxRenderer.GetGlyphSize(g, _ CheckBoxState.UncheckedNormal).Width .Y = Me.ClientRectangle.Y .Width = Me.ClientRectangle.Width - _ CheckBoxRenderer.GetGlyphSize(g, _ CheckBoxState.UncheckedNormal).Width .Height = Me.ClientRectangle.Height End With End Using Return textRectangleValue End Get End Property ' Draw the check box in the current state. Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) MyBase.OnPaint(e) CheckBoxRenderer.DrawCheckBox(e.Graphics, _ Me.ClientRectangle.Location, TextRectangle, Me.Text, _ Me.Font, TextFormatFlags.HorizontalCenter, _ clicked, state) End Sub ' Draw the check box in the checked or unchecked state, alternately. Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs) MyBase.OnMouseDown(e) If Not clicked Then With Me .clicked = True .Text = "Clicked!" .state = CheckBoxState.CheckedPressed End With Invalidate() Else With Me .clicked = False .Text = "Click here" .state = CheckBoxState.UncheckedNormal End With Invalidate() End If End Sub ' Draw the check box in the hot state. Protected Overrides Sub OnMouseHover(ByVal e As EventArgs) MyBase.OnMouseHover(e) If clicked Then state = CheckBoxState.CheckedHot Else state = CheckBoxState.UncheckedHot End If Invalidate() End Sub ' Draw the check box in the hot state. Protected Overrides Sub OnMouseUp(ByVal e As MouseEventArgs) MyBase.OnMouseUp(e) Me.OnMouseHover(e) End Sub ' Draw the check box in the unpressed state. Protected Overrides Sub OnMouseLeave(ByVal e As EventArgs) MyBase.OnMouseLeave(e) If clicked Then state = CheckBoxState.CheckedNormal Else state = CheckBoxState.UncheckedNormal End If Invalidate() End Sub End Class End Namespace
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.