The VB version of the Flip Task Bar for Vista Desktop Window Manager

Article
05/22/2007

In this post: Create your own Flip Task Bar with live thumbnails using Vista Desktop Window Manager DWM, I showed Fox code on creating your own Flip Task bar

Here is the VB.Net version that does the same thing…

File->New->Project->Visual Basic->Windows->Windows Forms Application

View->Code

Paste and run the code below.

Imports System

Imports System.Text

Imports System.Runtime.InteropServices

Public Class Form1

Dim ThumbWidth = 300

Dim ThumbHeight = ThumbWidth * My.Computer.Screen.Bounds.Height / My.Computer.Screen.Bounds.Width

Dim WithEvents cmdQuit As New Button

Dim WithEvents cmdRefresh As New Button

Dim WithEvents oSlider As New TrackBar

Dim WithEvents oTimer As New Timer

Delegate Function EnumWindowsCallback(ByVal hWnd As IntPtr, ByVal lParam As Integer) As Boolean

Declare Ansi Function EnumChildWindows Lib "user32.dll" (ByVal hwnd As IntPtr, ByVal MyCallBack As EnumWindowsCallback, ByVal lParam As Integer) As Boolean

Declare Ansi Function GetWindowTextA Lib "user32.dll" (ByVal hwnd As IntPtr, ByVal Str As StringBuilder, ByVal lSize As Integer) As Integer

Declare Function GetWindowLongA Lib "user32.dll" (ByVal hwnd As IntPtr, ByVal num As Integer) As Integer

Declare Function DwmRegisterThumbnail Lib "dwmapi.dll" (ByVal hWndDest As IntPtr, ByVal hWndSrc As IntPtr, ByRef dwThumb As IntPtr) As Integer

Declare Function DwmUpdateThumbnailProperties Lib "dwmapi.dll" (ByVal hThumb As IntPtr, ByRef dwmp As DWM_PROPERTIES) As Integer

Declare Function DwmUnregisterThumbnail Lib "dwmapi.dll" (ByVal hThumb As IntPtr) As Integer

<StructLayout(LayoutKind.Sequential)> _

Structure POINT

Dim x As Integer

Dim y As Integer

End Structure

<StructLayout(LayoutKind.Sequential)> _

Structure Rect

Sub New(ByVal _left As Integer, ByVal _top As Integer, ByVal _right As Integer, ByVal _bottom As Integer)

Left = _left

Right = _right

Top = _top

Bottom = _bottom

End Sub

Dim Left As Integer

Dim Top As Integer

Dim Right As Integer

Dim Bottom As Integer

End Structure

<StructLayout(LayoutKind.Sequential)> _

Structure DWM_PROPERTIES

Dim dwFlags As Integer

Dim rcDest As Rect

Dim rcSrc As Rect

Dim opacity As Byte

Dim fVisible As Boolean

Dim fSourceClientAreaOnly As Boolean

End Structure

Const DWM_TNP_VISIBLE = 8

Const DWM_TNP_RECTDESTINATION = 1

Const DWM_TNP_OPACITY = 4

Const GWL_STYLE = -16

Const WS_VISIBLE = &H10000000

Const WS_BORDER = &H800000

Class MyWindowItem

Implements IDisposable

Public hWnd As Integer

Public Title As String

Public Tid As IntPtr

Public oPictureBox As MyPictureBox

Public oLabel As Label

Sub New(ByVal _hWnd As Integer, ByVal _title As String)

hWnd = _hWnd

Title = _title

End Sub

Public Sub Dispose1() Implements System.IDisposable.Dispose

If Tid <> 0 Then

DwmUnregisterThumbnail(Tid)

Tid = 0

End If

If oPictureBox IsNot Nothing Then

Form1.Controls.Remove(oPictureBox)

End If

If oLabel IsNot Nothing Then

Form1.Controls.Remove(oLabel)

End If

End Sub

Protected Overrides Sub finalize()

Dispose1()

MyBase.Finalize()

End Sub

End Class

Dim WindowList As New SortedList

Dim nNewWindowsFound As Integer

Dim nTotalWindowsFound As Integer

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Me.Width = My.Computer.Screen.Bounds.Width

Me.Height = 180

Me.Left = 0

Me.Top = 0

Me.MinimizeBox = False ' no minimize box, so it stays up if user minimizes all

With cmdQuit

.Text = "&Quit"

End With

With cmdRefresh

.Text = "&Refresh"

.Left = 100

End With

With oSlider

.Left = 200

.Minimum = 1

.Maximum = 100

.Value = 50

.LargeChange = 10

.SmallChange = 2

.Height = 400

End With

Me.Controls.Add(cmdQuit)

Me.Controls.Add(cmdRefresh)

Me.Controls.Add(oSlider)

oTimer.Interval = 2000

oTimer.Enabled = True

End Sub

Sub GetHWnds(Optional ByVal fForce As Boolean = True)

If Not fForce Then

nNewWindowsFound = 0

nTotalWindowsFound = 0

Dim nOrigWindowCount = WindowList.Count

EnumChildWindows(0, AddressOf MyCallBack, 0)

If 0 = nNewWindowsFound And nOrigWindowCount = nTotalWindowsFound Then ' no new windows found or none deleted

Return

End If

Dim indx As Integer

Dim cWind As MyWindowItem

For indx = 0 To WindowList.Count - 1

cWind = WindowList.GetByIndex(indx)

cWind.Dispose1()

WindowList.Clear()

nNewWindowsFound = 0

EnumChildWindows(0, AddressOf MyCallBack, 0)

Dim tid As Integer = 0

Dim i = 0

Dim x = 0

Dim y = 20

Dim nRatio = Me.oSlider.Value / Me.oSlider.Maximum

For indx = 0 To WindowList.Count - 1

cWind = WindowList.GetByIndex(indx)

Dim oMyPictureBox As New MyPictureBox

Me.Controls.Add(oMyPictureBox)

With oMyPictureBox

.Left = x

.Top = y

.Height = ThumbHeight * nRatio

.Width = ThumbWidth * nRatio

.GetThumb(cWind)

.Visible = True

End With

cWind.oPictureBox = oMyPictureBox

Dim oLbl As New Label

With oLbl

.Left = x

.Top = y + ThumbHeight * nRatio

.Width = ThumbWidth * nRatio

.Height = 20

.Text = cWind.Title

.Visible = True

End With

cWind.oLabel = oLbl

Me.Controls.Add(oLbl)

x += Me.ThumbWidth * nRatio

If x + Me.ThumbWidth * nRatio > My.Computer.Screen.Bounds.Width Then

x = 0

y += Me.ThumbHeight * nRatio + 20

End If

End Sub

Function MyCallBack(ByVal hWnd As IntPtr, ByVal lParam As Integer) As Boolean

If Me.Handle <> hWnd Then '' if it's not our form

Dim nStyle = GetWindowLongA(hWnd, GWL_STYLE)

If (nStyle And (WS_VISIBLE + WS_BORDER)) = (WS_VISIBLE + WS_BORDER) Then

Dim Caption As New StringBuilder("", 500)

GetWindowTextA(hWnd, Caption, Caption.Capacity)

Dim c As String = Caption.ToString

nTotalWindowsFound += 1

If Not WindowList.ContainsKey(hWnd.ToString) Then

WindowList.Add(hWnd.ToString, New MyWindowItem(hWnd, Caption.ToString))

nNewWindowsFound += 1

End If

Return True

End Function

Private Sub cmdQuit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmdQuit.Click

Me.Close()

End Sub

Private Sub cmdRefresh_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmdRefresh.Click

GetHWnds()

End Sub

Private Sub Form1_Shown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shown

GetHWnds()

End Sub

Private Sub Form1_SizeChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.SizeChanged

End Sub

Private Sub oSlider_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles oSlider.ValueChanged

GetHWnds()

End Sub

Private Sub oTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles oTimer.Tick

GetHWnds(False)

End Sub

Class MyPictureBox

Inherits PictureBox

Const WS_MINIMIZE = &H20000000

Const SW_RESTORE = &H9

Dim oMyWindow As MyWindowItem

Sub GetThumb(ByVal _oMyWindow As MyWindowItem)

oMyWindow = _oMyWindow

DwmRegisterThumbnail(Me.Parent.Handle, oMyWindow.hWnd, oMyWindow.Tid)

Dim dwmp As New DWM_PROPERTIES

dwmp.opacity = 255

dwmp.fVisible = True

dwmp.rcDest = New Rect(Left, Top, Right, Bottom)

' dwmp.rcSrc = New Rect(0, 0, 200, 200)

dwmp.dwFlags = DWM_TNP_VISIBLE + DWM_TNP_RECTDESTINATION + DWM_TNP_OPACITY

DwmUpdateThumbnailProperties(oMyWindow.Tid, dwmp)

End Sub

<StructLayout(LayoutKind.Sequential)> _

Structure WindowPlacement

Dim length As Integer

Dim flags As Integer

Dim showcmd As Integer

Dim ptMinPosition As POINT

Dim ptMaxPosition As POINT

Dim rcNormalPosition As Rect

End Structure

' Declare Ansi Function GetWindowPlacement Lib "user32.dll" (ByVal hwnd As IntPtr, ByRef wp As WindowPlacement) As Integer

<DllImport("user32.dll", SetLastError:=True)> Shared Function GetWindowPlacement(ByVal hWnd As IntPtr, ByRef wp As WindowPlacement) As Integer

End Function

Declare Ansi Function SetWindowPlacement Lib "user32.dll" (ByVal hwnd As IntPtr, ByRef wp As WindowPlacement) As Boolean

Declare Function SetForegroundWindow Lib "user32.dll" (ByVal hWnd As IntPtr) As Integer

Sub MyClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Click

Dim nStyle = GetWindowLongA(oMyWindow.hWnd, GWL_STYLE)

If (nStyle And WS_MINIMIZE) = (WS_MINIMIZE) Then

Dim pPlacement As New WindowPlacement

pPlacement.length = 11 * 4

If GetWindowPlacement(oMyWindow.hWnd, pPlacement) > 0 Then

pPlacement.showcmd = SW_RESTORE

SetWindowPlacement(oMyWindow.hWnd, pPlacement)

Else

Dim n = Marshal.GetLastWin32Error()

Console.WriteLine(n)

End If

SetForegroundWindow(oMyWindow.hWnd)

End Sub

End Class

End of code

The VB version of the Flip Task Bar for Vista Desktop Window Manager

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