Move Form Event?

[norden]

Is is possible to catch the Move Event of a form without using a message handler?

[crptcblade]

By 'using a message handler', do you mean subclassing?

If so, then the only other way is to use a timer and check the position against the old position. But that's not a very nice way.

[norden]

Thanks for you quick response crptcblade.

I hope there is another way to get around it.

Thanks again...

-Pls excuse my grammar-

[manavo11]

Here's some code (that I found somewhere around here) that forces your form to stay on the screen. Just change the WM_MOVING case code as you need :

'** In a standard module
Option Explicit
 
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, _
                                                                            ByVal nIndex As Long, _
                                                                            ByVal dwNewLong As Long) _
                                                                            As Long
Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, _
                                                                              ByVal hwnd As Long, _
                                                                              ByVal Msg As Long, _
                                                                              ByVal wParam As Long, _
                                                                              ByVal lParam As Long) _
                                                                              As Long
Private Declare Function DefWindowProc Lib "user32" Alias "DefWindowProcA" (ByVal hwnd As Long, _
                                                                            ByVal wMsg As Long, _
                                                                            ByVal wParam As Long, _
                                                                            ByVal lParam As Long) _
                                                                            As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, _
                                                                     Source As Any, _
                                                                     ByVal Length As Long)
 
Private Const GWL_WNDPROC = (-4)
Private Const WM_MOVING = &H216
 
Private Const WMSZ_LEFT = 1
Private Const WMSZ_RIGHT = 2
Private Const WMSZ_TOP = 3
Private Const WMSZ_TOPLEFT = 4
Private Const WMSZ_TOPRIGHT = 5
Private Const WMSZ_BOTTOM = 6
Private Const WMSZ_BOTTOMLEFT = 7
Private Const WMSZ_BOTTOMRIGHT = 8
 
Private Type RECT
    Left As Long
    Top As Long
    Right As Long
    Bottom As Long
End Type
 
Private mPrevProc As Long
 
Public Sub Hook(ByVal hwnd As Long)
    mPrevProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf WndProc)
End Sub
 
Public Sub Unhook(ByVal hwnd As Long)
    
    Call SetWindowLong(hwnd, GWL_WNDPROC, mPrevProc)
    mPrevProc = 0&
    
End Sub
 
Private Function PScreenWidth() As Long
    PScreenWidth = (Screen.Width \ 15)
End Function
 
Private Function PScreenHeight() As Long
    PScreenHeight = (Screen.Height \ 15)
End Function
 
 
Public Function WndProc(ByVal hwnd As Long, ByVal uMsg As Long, _
                        ByVal wParam As Long, ByVal lParam As Long) _
                        As Long
On Error Resume Next
 
Dim r As RECT
Dim lTemp As Long
 
    If uMsg = WM_MOVING Then
        Call CopyMemory(r, ByVal lParam, Len(r))
        
        If r.Left < 0 Then
            lTemp = r.Right - r.Left
            r.Left = 0
            r.Right = lTemp
        End If
        If r.Right > PScreenWidth Then
            lTemp = r.Right - r.Left
            r.Right = PScreenWidth
            r.Left = r.Right - lTemp
        End If
        If r.Top < 0 Then
            lTemp = r.Bottom - r.Top
            r.Top = 0
            r.Bottom = lTemp
        End If
        If r.Bottom > PScreenHeight Then
            lTemp = r.Bottom - r.Top
            r.Bottom = PScreenHeight
            r.Top = r.Bottom - lTemp
        End If
        
        Call CopyMemory(ByVal lParam, r, Len(r))
    End If
 
    If mPrevProc& Then
        WndProc = CallWindowProc(mPrevProc, hwnd, uMsg, wParam, lParam)
    Else
        WndProc = DefWindowProc(hwnd, uMsg, wParam, lParam)
    End If
 
End Function

'** In your form
Option Explicit
 
Private Sub Form_Load()
    Call Hook(Me.hwnd)
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
    Call Unhook(Me.hwnd)
End Sub

[norden]

Thanks manavo11, but I really don't want to subclass it if possible.

[Merrion]

You could install a WH_CBT hook which would notify you if any of your forms moved - although if you are shy of subclassing then hooking is probably anaethema to you....

How about a component that does the subclassing on your behalf?

[manavo11]

Originally posted by norden
Thanks manavo11, but I really don't want to subclass it if possible.

If you don't mind me asking, why? (BTW I hadn't seen your post)