Option Explicit
'Declaraciones Api
'*************************************
'Retorna un handle de ventana
Public Declare Function FindWindow _
  Lib "user32" _
  Alias "FindWindowA" ( _
    ByVal lpClassName As String, _
    ByVal lpWindowName As String) As Long

'Enumera las ventanas hijas a partir de una superior
Public Declare Function EnumChildWindows _
  Lib "user32" ( _
    ByVal hWndParent As Long, _
    ByVal lpEnumFunc As Long, _
    ByVal lParam As Long) As Long

'Devuelve el texto de una ventana a partir del handle
Public Declare Function GetWindowText _
  Lib "user32" _
  Alias "GetWindowTextA" ( _
    ByVal hwnd As Long, _
    ByVal lpString As String, _
    ByVal cch As Long) As Long

'REcupera el nombre de la clase de ventana a partir del handle
Public Declare Function GetClassName _
  Lib "user32" _
  Alias "GetClassNameA" ( _
    ByVal hwnd As Long, _
    ByVal lpClassName As String, _
    ByVal nMaxCount As Long) As Long

Public Declare Function SendMessage _
  Lib "user32" _
  Alias "SendMessageA" ( _
    ByVal hwnd As Long, _
    ByVal wMsg As Long, _
    ByVal wParam As Long, _
    lParam As Any) As Long

'Apis para usar un temporizador
Public Declare Function SetTimer _
  Lib "user32" ( _
    ByVal hwnd As Long, _
    ByVal nIDEvent As Long, _
    ByVal uElapse As Long, _
    ByVal lpTimerFunc As Long) As Long

Public Declare Function KillTimer _
  Lib "user32" ( _
    ByVal hwnd As Long, _
    ByVal nIDEvent As Long) As Long

Private Declare Function GetWindowThreadProcessId _
  Lib "user32" ( _
    ByVal hwnd As Long, _
    lpdwProcessId As Long) As Long

Private Declare Function ReadProcessMemory _
  Lib "kernel32" ( _
    ByVal hProcess As Long, _
    lpBaseAddress As Any, _
    lpBuffer As Any, _
    ByVal nSize As Long, _
    lpNumberOfBytesWritten As Long) As Long

Private Declare Function WriteProcessMemory _
  Lib "kernel32" ( _
    ByVal hProcess As Long, _
    lpBaseAddress As Any, _
    lpBuffer As Any, _
    ByVal nSize As Long, _
    lpNumberOfBytesWritten As Long) As Long

Private Declare Function OpenProcess _
  Lib "kernel32" ( _
    ByVal dwDesiredAccess As Long, _
    ByVal bInheritHandle As Long, _
    ByVal dwProcessId As Long) As Long

'Constantes
'****************************************

Const PROCESS_VM_OPERATION = &H8
Const PROCESS_VM_READ = &H10
Const PROCESS_VM_WRITE = &H20
Const PROCESS_ALL_ACCESS = 0
Private Const PAGE_READWRITE = &H4&

Const MEM_COMMIT = &H1000
Const MEM_RESERVE = &H2000
Const MEM_DECOMMIT = &H4000
Const MEM_RELEASE = &H8000
Const MEM_FREE = &H10000
Const MEM_PRIVATE = &H20000
Const MEM_MAPPED = &H40000
Const MEM_TOP_DOWN = &H100000

Private Declare Function VirtualAllocEx _
  Lib "kernel32" ( _
    ByVal hProcess As Long, _
    ByVal lpAddress As Long, _
    ByVal dwSize As Long, _
    ByVal flAllocationType As Long, _
    ByVal flProtect As Long) As Long
    
Private Declare Function VirtualFreeEx _
  Lib "kernel32" ( _
    ByVal hProcess As Long, _
    lpAddress As Any, _
    ByVal dwSize As Long, _
    ByVal dwFreeType As Long) As Long
    
Private Declare Function CloseHandle _
  Lib "kernel32" ( _
    ByVal hObject As Long) As Long

'Constantes para el ListView de la ventana del administrador de tareas
Private Const LVM_FIRST = &H1000
Private Const LVM_GETTITEMCOUNT& = (LVM_FIRST + 4)

Private Const ILVM_GETITEMW = (LVM_FIRST + 75)
Private Const LVIF_TEXT = &H1
Private Const LVM_DELETEITEM = 4104


Public Type LV_ITEM
  mask As Long
  iItem As Long
  iSubItem As Long
  state As Long
  stateMask As Long
  lpszText As Long 'LPCSTR
  cchTextMax As Long
  iImage As Long
  lParam As Long
  iIndent As Long
End Type

Type LV_TEXT
  sItemText As String * 80
End Type


Public Function Procesos(ByVal hWnd2 As Long, _
             lParam As String) As Boolean
 
 Dim Nombre As String * 255, nombreClase As String * 255
 Dim Nombre2 As String, nombreClase2 As String
 Dim X As Long, Y As Long
 X = GetWindowText(hWnd2, Nombre, 255)
 Y = GetClassName(hWnd2, nombreClase, 255)
 'Buffers
 Nombre = Left$(Nombre, X)
 nombreClase = Left$(nombreClase, Y)
 
 Nombre2 = Trim$(Nombre)
 nombreClase2 = Trim$(nombreClase)
 
 'SysListView32 es el nombre de clase del LV del Administrador de T
 If nombreClase2 = "SysListView32" And Nombre2 = "Procesos" Then
   OcultarItems (hWnd2)
   Exit Function
 End If
 
 If Nombre2 = "" And nombreClase2 = "" Then
   Procesos = False
 Else
   Procesos = True
 End If
End Function

'A esta función se le pasa el Handle del ListView del Administrador de tareas _
que es obtenido desde la función " Procesos "
Private Function OcultarItems(ByVal hListView As Long) ' As Variant
  Dim pid As Long, tid As Long
  Dim hProceso As Long, nElem As Long, lEscribiendo As Long, i As Long
  Dim DirMemComp As Long, dwTam As Long
  Dim DirMemComp2 As Long
  Dim sLVItems() As String
  Dim li As LV_ITEM
  Dim lt As LV_TEXT
  If hListView = 0 Then Exit Function
  tid = GetWindowThreadProcessId(hListView, pid)
  
  'Obtiene el número de items del ListView
  nElem = SendMessage(hListView, LVM_GETTITEMCOUNT, 0, 0&)
  
  If nElem = 0 Then Exit Function
  
  ReDim sLVItems(nElem - 1)
  
  li.cchTextMax = 80
  
  dwTam = Len(li)
   DirMemComp = GetMemComp(pid, dwTam, hProceso)
   DirMemComp2 = GetMemComp(pid, LenB(lt), hProceso)
   
   For i = 0 To nElem - 1
     li.lpszText = DirMemComp2
     li.cchTextMax = 80
     li.iItem = i
     li.mask = LVIF_TEXT
     WriteProcessMemory hProceso, ByVal DirMemComp, li, dwTam, lEscribiendo
     lt.sItemText = Space(80)
     WriteProcessMemory hProceso, ByVal DirMemComp2, lt, LenB(lt), lEscribiendo
     
     'Recupera un item del LV
     Call SendMessage(hListView, LVM_GETITEMW, 0, ByVal DirMemComp)
     Call ReadProcessMemory(hProceso, ByVal DirMemComp2, lt, LenB(lt), lEscribiendo)
     
     'Acá verifica si lt.sItemText es el nombre del exe. Si está Lo elimina
     
     If TrimNull(StrConv(lt.sItemText, vbFromUnicode)) = App.EXEName & ".exe" Then
      Call SendMessage(hListView, LVM_DELETEITEM, i, 0)
      Exit Function
     End If
   Next i
   
   CloseMemComp hProceso, DirMemComp, dwTam
   CloseMemComp hProceso, DirMemComp2, LenB(lt)

End Function

Private Function GetMemComp(ByVal pid As Long, _
              ByVal memTam As Long, _
              hProceso As Long) As Long
  
  hProceso = OpenProcess(PROCESS_VM_OPERATION Or PROCESS_VM_READ _
              Or PROCESS_VM_WRITE, False, pid)
  GetMemComp = VirtualAllocEx(ByVal hProceso, ByVal 0&, ByVal memTam, _
              MEM_RESERVE Or MEM_COMMIT, PAGE_READWRITE)
End Function

Private Sub CloseMemComp(ByVal hProceso As Long, _
             ByVal DirMem As Long, _
             ByVal memTam As Long)
  
  Call VirtualFreeEx(hProceso, ByVal DirMem, memTam, MEM_RELEASE)
  CloseHandle hProceso

End Sub

'Elimina los nulos
Private Function TrimNull(sInput As String) As String
  Dim pos As Integer
  pos = InStr(sInput, Chr$(0))
  If pos Then
   TrimNull = Left$(sInput, pos - 1)
   Exit Function
  End If
  TrimNull = sInput
End Function

'Temporizador que cheaquea constantemente si el Administrador de tareas está ejecutandose
Public Sub TimerProc(ByVal hwnd As Long, _
           ByVal nIDEvent As Long, _
           ByVal uElapse As Long, _
           ByVal lpTimerFunc As Long)
  
  Dim Handle As Long
  'Se obtiene el HWND del administrador de tareas
  Handle = FindWindow(vbNullString, "Administrador de tareas de Windows")

  'Si el administrador está visible el handle es distinto de 0 _
  y se llama a EnumChildWindows pasandole el Handle del AT y la dirección _
  de la función Procesos. EnumChildWindows obtiene el handle del ListView
  If Handle <> 0 Then
    EnumChildWindows Handle, AddressOf Procesos, 1
  End If
End Sub

'Oculta y visualiza el item del proceso
Public Sub Ocultar(ByVal hwnd As Long)
  App.TaskVisible = False
  SetTimer hwnd, 0, 20, AddressOf TimerProc
End Sub

Public Sub Mostrar(ByVal hwnd As Long)
  App.TaskVisible = True
  KillTimer hwnd, 0
End Sub

'Oculta el proceso del Administrador de Tareas
Private Sub Command1_Click()
  Ocultar Me.hwnd
End Sub

'Visualiza el proceso
Private Sub Command2_Click()
  Mostrar Me.hwnd
End Sub