Public Class DoubleTrackBar
Inherits Control
Public Sub New()
Me.DoubleBuffered = True
Me.SetDefaults()
End Sub
Private Sub SetDefaults()
Me.Orientation = Windows.Forms.Orientation.Horizontal
Me.SmallChange = 1
Me.Maximum = 10
Me.Minimum = 0
Me.ValueLeft = 0
Me.ValueRight = 7
End Sub
#Region " Private Fields "
Private leftThumbState As VisualStyles.TrackBarThumbState
Private rightThumbState As VisualStyles.TrackBarThumbState
Private draggingLeft, draggingRight As Boolean
#End Region
#Region " Enums "
Public Enum Thumbs
None = 0
Left = 1
Right = 2
End Enum
#End Region
#Region " Properties "
Private _SelectedThumb As Thumbs
'''
''' Gets the thumb that had focus last.
'''
''' The thumb that had focus last.
_
Public Property SelectedThumb() As Thumbs
Get
Return _SelectedThumb
End Get
Private Set(value As Thumbs)
_SelectedThumb = value
End Set
End Property
Private _ValueLeft As Integer
'''
''' Gets or sets the position of the left slider.
'''
''' The position of the left slider.
_
Public Property ValueLeft() As Integer
Get
Return _ValueLeft
End Get
Set(ByVal value As Integer)
If value < Me.Minimum OrElse value > Me.Maximum Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'ValueLeft'. 'ValueLeft' should be between 'Minimum' and 'Maximum'.", value.ToString()), "ValueLeft")
End If
If value > Me.ValueRight Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'ValueLeft'. 'ValueLeft' should be less than or equal to 'ValueRight'.", value.ToString()), "ValueLeft")
End If
_ValueLeft = value
Me.OnValueChanged(EventArgs.Empty)
Me.OnLeftValueChanged(EventArgs.Empty)
Me.Invalidate()
End Set
End Property
Private _ValueRight As Integer
'''
''' Gets or sets the position of the right slider.
'''
''' The position of the right slider.
_
Public Property ValueRight() As Integer
Get
Return _ValueRight
End Get
Set(ByVal value As Integer)
If value < Me.Minimum OrElse value > Me.Maximum Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'ValueRight'. 'ValueRight' should be between 'Minimum' and 'Maximum'.", value.ToString()), "ValueRight")
End If
If value < Me.ValueLeft Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'ValueRight'. 'ValueRight' should be greater than or equal to 'ValueLeft'.", value.ToString()), "ValueLeft")
End If
_ValueRight = value
Me.OnValueChanged(EventArgs.Empty)
Me.OnRightValueChanged(EventArgs.Empty)
Me.Invalidate()
End Set
End Property
Private _Minimum As Integer
'''
''' Gets or sets the minimum value.
'''
''' The minimum value.
_
Public Property Minimum() As Integer
Get
Return _Minimum
End Get
Set(ByVal value As Integer)
If value >= Me.Maximum Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'Minimum'. 'Minimum' should be less than 'Maximum'.", value.ToString()), "Minimum")
End If
_Minimum = value
Me.Invalidate()
End Set
End Property
Private _Maximum As Integer
'''
''' Gets or sets the maximum value.
'''
''' The maximum value.
_
Public Property Maximum() As Integer
Get
Return _Maximum
End Get
Set(ByVal value As Integer)
If value <= Me.Minimum Then
Throw New ArgumentException(String.Format("Value of '{0}' is not valid for 'Maximum'. 'Maximum' should be greater than 'Minimum'.", value.ToString()), "Maximum")
End If
_Maximum = value
Me.Invalidate()
End Set
End Property
Private _Orientation As Orientation
'''
''' Gets or sets the orientation of the control.
'''
''' The orientation of the control.
_
Public Property Orientation() As Orientation
Get
Return _Orientation
End Get
Set(ByVal value As Orientation)
_Orientation = value
End Set
End Property
Private _SmallChange As Integer
'''
''' Gets or sets the amount of positions the closest slider moves when the control is clicked.
'''
''' The amount of positions the closest slider moves when the control is clicked.
_
Public Property SmallChange() As Integer
Get
Return _SmallChange
End Get
Set(ByVal value As Integer)
_SmallChange = value
End Set
End Property
Private ReadOnly Property RelativeValueLeft As Double
Get
Dim diff = Me.Maximum - Me.Minimum
Return If(diff = 0, Me.ValueLeft, Me.ValueLeft / diff)
End Get
End Property
Private ReadOnly Property RelativeValueRight As Double
Get
Dim diff = Me.Maximum - Me.Minimum
Return If(diff = 0, Me.ValueLeft, Me.ValueRight / diff)
End Get
End Property
#End Region
#Region " Methods "
Public Sub IncrementLeft()
Dim newValue = Math.Min(Me.ValueLeft + 1, Me.Maximum)
If Me.IsValidValueLeft(newValue) Then
Me.ValueLeft = newValue
End If
Me.Invalidate()
End Sub
Public Sub IncrementRight()
Dim newValue = Math.Min(Me.ValueRight + 1, Me.Maximum)
If Me.IsValidValueRight(newValue) Then
Me.ValueRight = newValue
End If
Me.Invalidate()
End Sub
Public Sub DecrementLeft()
Dim newValue = Math.Max(Me.ValueLeft - 1, Me.Minimum)
If Me.IsValidValueLeft(newValue) Then
Me.ValueLeft = newValue
End If
Me.Invalidate()
End Sub
Public Sub DecrementRight()
Dim newValue = Math.Max(Me.ValueRight - 1, Me.Minimum)
If Me.IsValidValueRight(newValue) Then
Me.ValueRight = newValue
End If
Me.Invalidate()
End Sub
Private Function IsValidValueLeft(ByVal value As Integer) As Boolean
Return (value >= Me.Minimum AndAlso value <= Me.Maximum AndAlso value < Me.ValueRight)
End Function
Private Function IsValidValueRight(ByVal value As Integer) As Boolean
Return (value >= Me.Minimum AndAlso value <= Me.Maximum AndAlso value > Me.ValueLeft)
End Function
Private Function GetLeftThumbRectangle(Optional ByVal g As Graphics = Nothing) As Rectangle
Dim shouldDispose = (g Is Nothing)
If shouldDispose Then g = Me.CreateGraphics()
Dim rect = Me.GetThumbRectangle(Me.RelativeValueLeft, g)
If shouldDispose Then g.Dispose()
Return rect
End Function
Private Function GetRightThumbRectangle(Optional ByVal g As Graphics = Nothing) As Rectangle
Dim shouldDispose = (g Is Nothing)
If shouldDispose Then g = Me.CreateGraphics()
Dim rect = Me.GetThumbRectangle(Me.RelativeValueRight, g)
If shouldDispose Then g.Dispose()
Return rect
End Function
Private Function GetThumbRectangle(ByVal relativeValue As Double, ByVal g As Graphics) As Rectangle
Dim size = TrackBarRenderer.GetBottomPointingThumbSize(g, VisualStyles.TrackBarThumbState.Normal)
Dim border = CInt(size.Width / 2)
Dim w = Me.GetTrackRectangle(border).Width
Dim x = CInt(Math.Abs(Me.Minimum) / (Me.Maximum - Me.Minimum) * w + relativeValue * w)
Dim y = CInt((Me.Height - size.Height) / 2)
Return New Rectangle(New Point(x, y), size)
End Function
Private Function GetTrackRectangle(ByVal border As Integer) As Rectangle
'TODO: Select Case for hor/ver
Return New Rectangle(border, CInt(Me.Height / 2) - 3, Me.Width - 2 * border - 1, 4)
End Function
Private Function GetClosestSlider(ByVal point As Point) As Thumbs
Dim leftThumbRect = Me.GetLeftThumbRectangle()
Dim rightThumbRect = Me.GetRightThumbRectangle()
If Me.Orientation = Windows.Forms.Orientation.Horizontal Then
If Math.Abs(leftThumbRect.X - point.X) > Math.Abs(rightThumbRect.X - point.X) _
AndAlso Math.Abs(leftThumbRect.Right - point.X) > Math.Abs(rightThumbRect.Right - point.X) Then
Return Thumbs.Right
Else
Return Thumbs.Left
End If
Else
If Math.Abs(leftThumbRect.Y - point.Y) > Math.Abs(rightThumbRect.Y - point.Y) _
AndAlso Math.Abs(leftThumbRect.Bottom - point.Y) > Math.Abs(rightThumbRect.Bottom - point.Y) Then
Return Thumbs.Right
Else
Return Thumbs.Left
End If
End If
End Function
Private Sub SetThumbState(ByVal location As Point, ByVal newState As VisualStyles.TrackBarThumbState)
Dim leftThumbRect = Me.GetLeftThumbRectangle()
Dim rightThumbRect = Me.GetRightThumbRectangle()
If leftThumbRect.Contains(location) Then
leftThumbState = newState
Else
If Me.SelectedThumb = Thumbs.Left Then
leftThumbState = VisualStyles.TrackBarThumbState.Hot
Else
leftThumbState = VisualStyles.TrackBarThumbState.Normal
End If
End If
If rightThumbRect.Contains(location) Then
rightThumbState = newState
Else
If Me.SelectedThumb = Thumbs.Right Then
rightThumbState = VisualStyles.TrackBarThumbState.Hot
Else
rightThumbState = VisualStyles.TrackBarThumbState.Normal
End If
End If
End Sub
Protected Overrides Sub OnMouseMove(ByVal e As System.Windows.Forms.MouseEventArgs)
MyBase.OnMouseMove(e)
Me.SetThumbState(e.Location, VisualStyles.TrackBarThumbState.Hot)
Dim offset = CInt(e.Location.X / (Me.Width) * (Me.Maximum - Me.Minimum))
Dim newValue = Me.Minimum + offset
If draggingLeft Then
If Me.IsValidValueLeft(newValue) Then Me.ValueLeft = newValue
ElseIf draggingRight Then
If Me.IsValidValueRight(newValue) Then Me.ValueRight = newValue
End If
Me.Invalidate()
End Sub
Protected Overrides Sub OnMouseDown(ByVal e As System.Windows.Forms.MouseEventArgs)
MyBase.OnMouseDown(e)
Me.Focus()
Me.SetThumbState(e.Location, VisualStyles.TrackBarThumbState.Pressed)
draggingLeft = (leftThumbState = VisualStyles.TrackBarThumbState.Pressed)
If Not draggingLeft Then draggingRight = (rightThumbState = VisualStyles.TrackBarThumbState.Pressed)
If draggingLeft Then
Me.SelectedThumb = Thumbs.Left
ElseIf draggingRight Then
Me.SelectedThumb = Thumbs.Right
End If
If Not draggingLeft AndAlso Not draggingRight Then
If Me.GetClosestSlider(e.Location) = 1 Then
If e.X < Me.GetLeftThumbRectangle().X Then
Me.DecrementLeft()
Else
Me.IncrementLeft()
End If
Me.SelectedThumb = Thumbs.Left
Else
If e.X < Me.GetRightThumbRectangle().X Then
Me.DecrementRight()
Else
Me.IncrementRight()
End If
Me.SelectedThumb = Thumbs.Right
End If
End If
Me.Invalidate()
End Sub
Protected Overrides Sub OnMouseUp(ByVal e As System.Windows.Forms.MouseEventArgs)
MyBase.OnMouseUp(e)
draggingLeft = False
draggingRight = False
Me.Invalidate()
End Sub
Protected Overrides Sub OnMouseWheel(e As System.Windows.Forms.MouseEventArgs)
MyBase.OnMouseWheel(e)
If e.Delta = 0 Then Return
If Me.SelectedThumb = 1 Then
If e.Delta > 0 Then
Me.IncrementLeft()
Else
Me.DecrementLeft()
End If
ElseIf Me.SelectedThumb = 2 Then
If e.Delta > 0 Then
Me.IncrementRight()
Else
Me.DecrementRight()
End If
End If
End Sub
Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
MyBase.OnPaint(e)
Dim thumbSize = Me.GetThumbRectangle(0, e.Graphics).Size
Dim trackRect = Me.GetTrackRectangle(CInt(thumbSize.Width / 2))
Dim ticksRect = trackRect : ticksRect.Offset(0, 15)
TrackBarRenderer.DrawVerticalTrack(e.Graphics, trackRect)
TrackBarRenderer.DrawHorizontalTicks(e.Graphics, ticksRect, Me.Maximum - Me.Minimum + 1, VisualStyles.EdgeStyle.Etched)
TrackBarRenderer.DrawBottomPointingThumb(e.Graphics, Me.GetLeftThumbRectangle(e.Graphics), leftThumbState)
TrackBarRenderer.DrawBottomPointingThumb(e.Graphics, Me.GetRightThumbRectangle(e.Graphics), rightThumbState)
End Sub
#End Region
#Region " Events "
Public Event ValueChanged As EventHandler
Public Event LeftValueChanged As EventHandler
Public Event RightValueChanged As EventHandler
Protected Overridable Sub OnValueChanged(e As EventArgs)
RaiseEvent ValueChanged(Me, e)
End Sub
Protected Overridable Sub OnLeftValueChanged(e As EventArgs)
RaiseEvent LeftValueChanged(Me, e)
End Sub
Protected Overridable Sub OnRightValueChanged(e As EventArgs)
RaiseEvent RightValueChanged(Me, e)
End Sub
#End Region
End Class