How to know window handle by process ID?

[allam]

Hi,

I initate another application with ShellEx, which return a process ID.

How can I figure out its window handle by the process ID? ( I don't want to find window handle by looking up its applicaton name b'coz there may be two Win Word application running simultaneously.

Your kind & prompt advise is much appreciated.


Thx,/Albert :-)

[SonGouki]

Here's how I do it:

'<<< CONSTANTS >>>
Private Const MAXSHORT As Integer = &H7FFF

Private Const GW_HWNDFIRST As Integer = 0
Private Const GW_HWNDLAST As Integer = 1
Private Const GW_HWNDNEXT As Integer = 2
Private Const GW_HWNDPREV As Integer = 3
Private Const GW_OWNER As Integer = 4
Private Const GW_CHILD As Integer = 5

'<<< API DECLARES >>>
Private Declare Function GetDesktopWindow _
                Lib "user32" _
                () As Long

Private Declare Function GetWindow _
                Lib "user32" _
                (ByVal hwnd As Long, ByVal wCmd As Long) As Long

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

'Function to retrieve the Handle based on a Process ID.
Private Function hGetAppHandle(hProcID As Long) As Long
   Dim hCurWindow As Long
   Dim hCurProcID As Long
   Dim hAppHandle As Long
   Dim iSafeStep As Integer
   
   hCurWindow = GetDesktopWindow
   hCurWindow = GetWindow(hCurWindow, GW_CHILD)
   
   Do While hCurWindow <> 0 And iSafeStep < MAXSHORT
      Call GetWindowThreadProcessId(hCurWindow, hCurProcID)
      
      If hCurProcID = hProcID Then
         hAppHandle = hCurWindow
         Exit Do
      End If
      
      hCurWindow = GetWindow(hCurWindow, GW_HWNDNEXT)
      iSafeStep = iSafeStep + 1
   Loop
   
   mhGetAppHandle = hAppHandle
End Function

The iSafeStep counter is used to ensure that the loop doesn't get caught in an infinite loop because of the nature of crashing programs and such.

If anyone has a better way of doing this I would like to know as well. It's the only way I know of and I would like to know if there is a better way.

Later.