How to Control the Placement of Desktop Windows

Step-by-Step Example

1. Start a new project in Visual Basic. Form1 is created by default.
2. Add a command button (Command1) to the form, and change its Caption property to Tile.
3. Add a code module (Module1) to the project by choosing New Module from the File menu (ALT, F, M).
4. Add the following code to the general declarations section of Module1:

      Type POINTAPI
         x As Integer
         y As Integer
      End Type
   
      Type RECT
         left As Integer
         top As Integer
         right As Integer
         bottom As Integer
      End Type
   
      Type WINDOWPLACEMENT
         length As Integer
         flags As Integer
         showCmd As Integer
         ptMinPosition As POINTAPI
         ptMaxPosition As POINTAPI
         rcNormalPosition As RECT
      End Type
   
      Global lpwndplOld As WINDOWPLACEMENT
      Global lpwndplNew As WINDOWPLACEMENT
   
      ' Enter each of the following Declare statements as one, single line:
   
      Declare Function FindWindow Lib "User" (ByVal lpClassName As Any,
         ByVal lpWindowName As Any) As Integer
      Declare Function GetWindowPlacement Lib "User" (ByVal hwnd As
         Integer, lpwndpl As WINDOWPLACEMENT) As Integer
      Declare Function SetWindowPlacement Lib "User" (ByVal hwnd As
         Integer, lpwndpl As WINDOWPLACEMENT) As Integer
   
      Global Const SW_SHOWNORMAL = 1
      Global hWnds() As Integer
   
   						

5. Add the following code to Module1:

      ' Enter the following Function statement as one, single line:
   
      Function Tile (hWndArr() As Integer, cardinal As Integer,
         HorV As Integer)
   
         Dim ordinal As Integer
         On Error GoTo handler
   
         Select Case HorV
   
         Case 1
   
         For ordinal = 1 To cardinal
   
         ' Optionally, check old placement of window:
         ' ****************************************************
         ' Note that the debug statements induce a slight delay
         ' Enter each Debug.Print statement as one, single line:
         '
         ' lpwndplOld.length = Len(lpwndplOld)
         ' ret% = GetWindowPlacement(hWndArr(ordinal), lpwndplOld)
         ' Debug.Print
         ' Debug.Print "ordinal= "; ordinal
         ' Enter the following two lines as one, single line:
         ' Debug.Print " Old window placement values for handle = ";
         '    Hex$(hWndArr(ordinal))
         ' Debug.Print "lpwndplOld.length= "; lpwndplOld.length
         ' Debug.Print "lpwndplOld.flags= "; lpwndplOld.flags
         ' Debug.Print "lpwndplOld.showCmd= "; lpwndplOld.showCmd
         '
         ' Debug.Print "lpwndplOld.ptMinPosition.x= ";
         '    lpwndplOld.ptMinPosition.x
         ' Debug.Print "lpwndplOld.ptMinPosition.y= ";
         '    lpwndplOld.ptMinPosition.y
         '
         ' Debug.Print "lpwndplOld.ptMaxPosition.x= ";
         '    lpwndplOld.ptMaxPosition.x
         ' Debug.Print "lpwndplOld.ptMaxPosition.y= ";
         '    lpwndplOld.ptMaxPosition.y
         '
         ' Debug.Print "lpwndplOld.rcNormalPosition.left= ";
         '    lpwndplOld.rcNormalPosition.left
         ' Debug.Print "lpwndplOld.rcNormalPosition.top= ";
         '    lpwndplOld.rcNormalPosition.top
         ' Debug.Print "lpwndplOld.rcNormalPosition.right= ";
         '    lpwndplOld.rcNormalPosition.right
         ' Debug.Print "lpwndplOld.rcNormalPosition.bottom= ";
         '    lpwndplOld.rcNormalPosition.bottom
         '**************************************************************
   
            lpwndplNew.length = Len(lpwndplNew)
            lpwndplNew.flags = 0
            lpwndplNew.showCmd = SW_SHOWNORMAL
   
            l = 0
   
            ' Enter the following two lines as one, single line:
            t = (ordinal - 1) *
               (screen.Height / screen.TwipsPerPixelY) \ cardinal
   
            r = (screen.Width / screen.TwipsPerPixelX)
            b = ordinal * (screen.Height / screen.TwipsPerPixelY) \ cardinal
   
            lpwndplNew.rcNormalPosition.left = l
            lpwndplNew.rcNormalPosition.top = t
            lpwndplNew.rcNormalPosition.right = r
            lpwndplNew.rcNormalPosition.bottom = b
   
            ret% = SetWindowPlacement(hWndArr(ordinal), lpwndplNew)
   
         Next ordinal
   
         Case 2
   
         For ordinal = 1 To cardinal
   
            lpwndplNew.length = Len(lpwndplNew)
            lpwndplNew.flags = 0
            lpwndplNew.showCmd = SW_SHOWNORMAL
   
            ' Enter the following two lines as one, single line:
            l = (ordinal - 1) *
               (screen.Width / screen.TwipsPerPixelX) \ cardinal
   
            t = 0
            r = ordinal * (screen.Width / screen.TwipsPerPixelX) \ cardinal
            b = (screen.Height / screen.TwipsPerPixelY)
            lpwndplNew.rcNormalPosition.left = l
            lpwndplNew.rcNormalPosition.top = t
            lpwndplNew.rcNormalPosition.right = r
            lpwndplNew.rcNormalPosition.bottom = b
   
            ret% = SetWindowPlacement(hWndArr(ordinal), lpwndplNew)
   
         Next ordinal
         End Select
         Tile = True
         Exit Function
   
         handler:
         MsgBox Error$
         Tile = False
         Exit Function
   
      End Function
   
   						

6. Add the following code to Command1_Click event procedure:

      Sub Command1_Click ()
         Dim orientation As Integer, handlecount As Integer, i As Integer
   
         ret% = Shell("notepad", 7)
         If FindWindow("NOTEPAD", 0&) Then
            handlecount = handlecount + 1
            ReDim Preserve hWnds(1 To handlecount)
            hWnds(handlecount) = FindWindow("NOTEPAD", 0&)
         End If
   
         ret% = Shell("write", 7)
         If FindWindow("MSWRITE_MENU", 0&) Then
            handlecount = handlecount + 1
            ReDim Preserve hWnds(1 To handlecount)
            hWnds(handlecount) = FindWindow("MSWRITE_MENU", 0&)
         End If
   
         handlecount = handlecount + 1
         ReDim Preserve hWnds(1 To handlecount)
         hWnds(handlecount) = Me.hWnd ' the handle of Form1
   
         ret% = Shell("calc", 7)
         If FindWindow("SCICALC", 0&) Then
            handlecount = handlecount + 1
            ReDim Preserve hWnds(1 To handlecount)
            hWnds(handlecount) = FindWindow("SCICALC", 0&)
         End If
   
         'orientation = 1 ' horizontal
         orientation = 2 ' vertical
   
         ret% = Tile(hWnds(), handlecount, orientation)
   
      End Sub
   
   						

7. Save the project and run the program by pressing the F5 key.
8. Click the Tile button, and observe the vertical tiling of the windows. Then stop the program, and close the three applications (CALC.EXE, WRITE.EXE, and NOTEPAD.EXE). Remove the single quotation mark from "orientation = 1" line. Then add a single quotation mark to the "orientation = 2" line. Run the program again, and observe the horizontal tiling.