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VB.NET ComboBoxRenderer類代碼示例

本文整理匯總了VB.NET中System.Windows.Forms.ComboBoxRenderer的典型用法代碼示例。如果您正苦於以下問題:VB.NET ComboBoxRenderer類的具體用法?VB.NET ComboBoxRenderer怎麽用?VB.NET ComboBoxRenderer使用的例子?那麽, 這裏精選的類代碼示例或許可以為您提供幫助。


在下文中一共展示了ComboBoxRenderer類的1個代碼示例,這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚,您的評價將有助於係統推薦出更棒的VB.NET代碼示例。

示例1: New

' 導入命名空間
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
開發者ID:VB.NET開發者,項目名稱:System.Windows.Forms,代碼行數:124,代碼來源:ComboBoxRenderer


注:本文中的System.Windows.Forms.ComboBoxRenderer類示例由純淨天空整理自Github/MSDocs等開源代碼及文檔管理平台,相關代碼片段篩選自各路編程大神貢獻的開源項目,源碼版權歸原作者所有,傳播和使用請參考對應項目的License;未經允許,請勿轉載。