wm_paint for specific window.

[Samy]

Hi , I am currently creating a program which deals with subclassing . I was wondering can I detect wm_paint for a particular window ?
There is assuming I know the caption of the window.

[Jop]

Well, it doesn't seem to work with programs outside your thread:

In a Module

Option Explicit

Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
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

Public Const WM_PAINT = &HF
Public Const GWL_WNDPROC = (-4)
Dim OldProc As Long
Public Sub SubClass(hWnd As Long)
    OldProc = SetWindowLong(hWnd, GWL_WNDPROC, AddressOf WindowProc)
    MsgBox "SubClassed"
End Sub
Public Sub unSubClass(hWnd As Long)
    SetWindowLong hWnd, GWL_WNDPROC, OldProc
End Sub
Public Function WindowProc(ByVal hWnd As Long, ByVal uMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    If uMsg = WM_PAINT Then
        Debug.Print "PAINTED"
    End If
    WindowProc = CallWindowProc(OldProc, hWnd, uMsg, wParam, lParam)
End Function

In a form:

Option Explicit
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long

Dim lNoteP&
Private Sub Form_Load()
lNoteP = FindWindow("Notepad", vbNullString)
If lNoteP <> 0 Then SubClass lNoteP: MsgBox lNoteP
'SubClass Me.hWnd
End Sub

Private Sub Form_Unload(Cancel As Integer)
unSubClass lNoteP
'unSubClass Me.hWnd
End Sub

If you uncomment the SubClass Me.Hwnd & UnSubClass Me.Hwnd you'll see it works, so I'm afraid it only works on your progs

Have Fun Though