Imports System.Drawing.Drawing2D
<System.ComponentModel.DefaultEvent("CheckedChanged")>
Public Class Android_Stock_ToggleSwitch
    Inherits Control
    Private T As Thumb
    Private Diff As Integer
    Private IsMouseDown As Boolean
    Public Event CheckedChanged(sender As Object)
    Private _checked As Boolean = False

    Public Property Checked As Boolean
        Get
            Return _checked
        End Get
        Set(value As Boolean)
            If value Then
                T.Rect.X = Width - T.Width
            Else
                T.Rect.X = 0
            End If
            If _checked <> value Then
                _checked = value
                RaiseEvent CheckedChanged(Me)
            End If
            Invalidate()
        End Set
    End Property

    Sub New()
        MyBase.New()
        SetStyle(ControlStyles.OptimizedDoubleBuffer Or ControlStyles.UserPaint Or ControlStyles.ResizeRedraw, True)
        BackColor = Color.FromArgb(39, 40, 41)
        Width = 120
        Height = 30
        T = New Thumb(Width \ 2, Height)
    End Sub
    Protected Overrides Sub OnPaint(e As PaintEventArgs)
        MyBase.OnPaint(e)
        If T.Rect.X < 2 Then T.Rect.X = 2
        If T.Rect.X > Width - T.Width Then T.Rect.X = Width - T.Width
        T.DrawThumb(e.Graphics, Check)
    End Sub
    Private Sub Toggler_SizeChanged(sender As Object, e As EventArgs) Handles Me.SizeChanged
        T = New Thumb(Width \ 2, Height)
        If Checked Then
            T.Rect.X = Width - T.Width
        End If
    End Sub
    Private Sub Toggler_MouseDown(sender As Object, e As MouseEventArgs) Handles Me.MouseDown
        If e.Button = Windows.Forms.MouseButtons.Left AndAlso T.Rect.IntersectsWith(New Rectangle(e.Location.X, e.Location.Y, 1, 1)) Then
            Diff = e.Location.X - T.Rect.X
            IsMouseDown = True
        End If
    End Sub
    Private Sub Toggler_MouseMove(sender As Object, e As MouseEventArgs) Handles Me.MouseMove
        If IsMouseDown Then
            T.Rect.X = e.Location.X - Diff
            Invalidate()
        End If
    End Sub
    Private Sub Toggler_MouseUp(sender As Object, e As MouseEventArgs) Handles Me.MouseUp
        Checked = Check()
        IsMouseDown = False
    End Sub

    Private Sub Toggler_Click(sender As Object, e As MouseEventArgs) Handles Me.Click
        If e.Button = Windows.Forms.MouseButtons.Left Then
            If Checked = True Then
                Checked = False
            Else
                Checked = True
            End If
        End If
    End Sub

    Private Function Check() As Boolean
        Select Case True
            Case Checked And T.Rect.X - 1 <= Width / 4
                Return False
            Case Checked And Not T.Rect.X - 1 <= Width / 4
                Return True
            Case Not Checked And T.Rect.X - 1 >= Width / 4
                Return True
            Case Not Checked And Not T.Rect.X - 1 >= Width / 4
                Return False
            Case Else
                Return Checked
        End Select
    End Function

    Private Class Thumb
        Private Textformat As New StringFormat With {.LineAlignment = StringAlignment.Center, .Alignment = StringAlignment.Center}
        Private Schriftart As New Font("Microsoft Sans Serif", 12, FontStyle.Bold)
        Public Width As Integer
        Public Height As Integer
        Public Rect As Rectangle
        Sub New(width As Integer, height As Integer)
            Me.Width = width
            Me.Height = height
            Rect = New Rectangle(2, 2, width - 3, height - 5)
        End Sub
        Public Sub DrawThumb(g As Graphics, drawChecked As Boolean)
            Using GP As GraphicsPath = New GraphicsPath
                GetRoundedPath(Rect, 2, GP)
                g.TextContrast = 0 '0 bis 12
                g.TextRenderingHint = Drawing.Text.TextRenderingHint.AntiAlias
                g.InterpolationMode = InterpolationMode.HighQualityBicubic
                g.CompositingQuality = CompositingQuality.GammaCorrected
                g.SmoothingMode = SmoothingMode.HighQuality
                Using SB As New SolidBrush(Color.FromArgb(50, 255, 255, 255))
                    Using p As New Pen(SB, 1)
                        If drawChecked Then 'ON
                            g.FillPath(New SolidBrush(Color.FromArgb(7, 129, 170)), GP) 'Schieber füllen
                            g.DrawString("ON", Schriftart, New SolidBrush(Color.FromArgb(189, 189, 189)), Rect, Textformat) 'Text zeichnen
                            g.SmoothingMode = SmoothingMode.HighQuality
                        Else 'OFF
                            g.FillPath(New SolidBrush(Color.FromArgb(84, 85, 86)), GP) 'Schieber füllen
                            g.DrawString("OFF", Schriftart, New SolidBrush(Color.FromArgb(189, 189, 189)), Rect, Textformat) 'Text zeichnen
                        End If
                        g.DrawLine(p, Rect.X + 2, 2, Rect.X + Rect.Width - 2, 2)
                    End Using
                End Using
            End Using
        End Sub

        Private Function GetRoundedPath(re As Rectangle, r As Integer, GP As GraphicsPath) As GraphicsPath
            GP.AddLine(re.X + r, re.Y, re.X + re.Width - r, re.Y)
            GP.AddArc(re.X + re.Width - r, re.Y, r, r, 270, 90)
            GP.AddLine(re.X + re.Width, re.Y + r, re.X + re.Width, re.Y + re.Height - r)
            GP.AddLine(re.X + re.Width - r, re.Y + re.Height, re.X + r, re.Y + re.Height)
            GP.AddLine(re.X, re.Y + re.Height - r, re.X, re.Y + r)
            GP.AddArc(re.X, re.Y, r, r, 180, 90)
            GP.CloseFigure()
            Return GP
        End Function

    End Class

End Class