[RESOLVED] FindWindowEx trouble

[jsublime]

I've read a lot about this but can't seem to get the code to work.

I don't have SPy++ but here the window I am trying to access:



I have attempted multiple examples of this:

Option Explicit On
'test module for accessing third party windows
Module Module2
    Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
    Public Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
    Private Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hWnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
    Private Declare Function GetClassName Lib "user32" Alias "GetClassNameA" (ByVal hWnd As Long, ByVal lpClassName As String, ByVal nMaxCount As Long) As Long

    Public Sub Form_Load()
        Dim lRet As Long

        lRet = FindWindow(vbNullString, "Home (Search)")
        If lRet = 0 Then Exit Sub
        lRet = FindWindowEx(me.hwand, lRet, vbNullString, vbNullString)
        Do While lRet <> 0
            ShowWindowInfo(lRet)
            lRet = FindWindowEx(me.hwand, lRet, vbNullString, vbNullString)
        Loop
    End Sub

    Private Sub ShowWindowInfo(ByVal hWnd As Long)
        Dim lRet As Long
        Dim buffer As String
        Dim message As String

        message = "Window handle: " & hWnd & vbCrLf

        buffer = Space(256)
        lRet = GetWindowText(hWnd, buffer, 256&)
        message = message & "Window text: " & Left$(buffer, lRet) & vbCrLf

        buffer = Space(256)
        lRet = GetClassName(hWnd, buffer, 256&)
        message = message & "Class name: " & Left$(buffer, lRet) & vbCrLf

        Debug.Print(message)
    End Sub

With this example I was expecting it to loop through all of the child windows of "Home (Search)". I'm getting an error on Me.hwnd since it is in a module. What do I need to replace Me with for this to execute properly?

[4x2y]

There is no need for Me.hwnd, because the first FindWindowEx's parameter is refer to the parent window handle which you already get by FindWindow, read more details about FindWindowEx

Option Explicit On
'test module for accessing third party windows
Module Module2
    Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
    Public Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
    Private Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hWnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
    Private Declare Function GetClassName Lib "user32" Alias "GetClassNameA" (ByVal hWnd As Long, ByVal lpClassName As String, ByVal nMaxCount As Long) As Long

    Public Sub Form_Load()
        Dim lngParent As Long
        Dim lngChild As Long

        lngParent = FindWindow(vbNullString, "Home (Search)")
        If lngParent <> 0 Then
            lngChild = FindWindowEx(lngParent, 0, vbNullString, vbNullString)
            Do While lngChild <> 0
                ShowWindowInfo(lngChild)
                lngChild = FindWindowEx(lngParent, lngChild, vbNullString, vbNullString)
            Loop
        End If
    End Sub

    Private Sub ShowWindowInfo(ByVal hWnd As Long)
        Dim lRet As Long
        Dim buffer As String
        Dim message As String

        message = "Window handle: " & hWnd & vbCrLf

        buffer = Space(256)
        lRet = GetWindowText(hWnd, buffer, 256&)
        message = message & "Window text: " & Left$(buffer, lRet) & vbCrLf

        buffer = Space(256)
        lRet = GetClassName(hWnd, buffer, 256&)
        message = message & "Class name: " & Left$(buffer, lRet) & vbCrLf

        Debug.Print(message)
    End Sub

End Module

[Doogle]

'me.hwand' is spelt incorrectly. To access the Form's hwnd within a Module, prefix it with the Form's name (eg Form1.hwnd)

[jsublime]

I tried your code 4x2y and I'm getting the following error:

pinvoke stack imbalance detected

lngChild = FindWindowEx(lngParent, 0, vbNullString, vbNullString)
A call to PInvoke function 'Metrics!Metrics.Module2::FindWindowEx' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.

The spelling error was a mistake becasue I was in a hurry earlier, I didn't have the same spelling in my code.

[Doogle]

Not sure about .Net but in VB6 all numeric literals are defaulted to Integer Types. I suspect this

lngChild = FindWindowEx(lngParent, 0, vbNullString, vbNullString)

needs to be changed to something like this

lngChild = FindWindowEx(lngParent, CLng(0), vbNullString, vbNullString)

[jsublime]

I'm getting the same error. I can f5 past it and the code is actually executing afterwards, but always breaks on that line.

[4x2y]

Long in VB6 is Integer/Int32 in VB.NET, so replace Long in all API declaration to Integer/Int32

Option Explicit On

Module Module2
    Private Declare Function FindWindow Lib "user32.dll" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Int32
    Private Declare Function FindWindowEx Lib "user32.dll" Alias "FindWindowExA" (ByVal hWndParent As Int32, ByVal hWndChildAfter As Int32, ByVal lpszClass As String, ByVal lpszWindow As String) As Int32
    Private Declare Function GetWindowText Lib "user32.dll" Alias "GetWindowTextA" (ByVal hwnd As Int32, ByVal lpString As String, ByVal cch As Int32) As Int32
    Private Declare Function GetClassName Lib "user32.dll" Alias "GetClassNameA" (ByVal hwnd As Int32, ByVal lpClassName As String, ByVal nMaxCount As Int32) As Int32

    Public Sub Form_Load()
        Dim lngParent As Int32
        Dim lngChild As Int32

        lngParent = FindWindow(vbNullString, "Home (Search)")
        If lngParent <> 0 Then
            lngChild = FindWindowEx(lngParent, 0, vbNullString, vbNullString)
            Do While lngChild <> 0
                ShowWindowInfo(lngChild)
                lngChild = FindWindowEx(lngParent, lngChild, vbNullString, vbNullString)
            Loop
        End If
    End Sub

    Private Sub ShowWindowInfo(ByVal hWnd As Long)
        Dim lRet As Int32
        Dim buffer As String
        Dim message As String

        message = "Window handle: " & hWnd & vbCrLf

        buffer = Space(256)
        lRet = GetWindowText(hWnd, buffer, 256&)
        message = message & "Window text: " & Left$(buffer, lRet) & vbCrLf

        buffer = Space(256)
        lRet = GetClassName(hWnd, buffer, 256&)
        message = message & "Class name: " & Left$(buffer, lRet) & vbCrLf

        Debug.Print(message)
    End Sub

End Module

[jsublime]

I did not realize this, thanks works great!