Launch a process in a designated monitor

see this discussion for how to do it properly for your own application: http://stackoverflow.com/questions/206400/start-program-on-a-second-monitor

now, I never played with a multimnonitor system, so you will need to do this yourself and report back if it succeeded or not, dn if not, what errors you get (btw,. did you check what error shellexecuteex returnes?it would help if you would give us the code).

look at this function: http://msdn.microsoft.com/en-us/library/ms534603(VS.85).aspx 
you will use this function to get the correct handle of the monitor using the Screen.Monitors[ x ].Left and top as desccribed in the first link. I figure since that works for your own application, getting the handle via monitorfrompoint should return a valid monitor handle which should work fine with shellexecuteex.

but, do not forget to tell us what error code shellexecuteex returns. we kind of need that to debug the issue ;)

ShellExecuteEx does not return any error whatsoever. It simply ignores the supplied monitor.

I am already getting the monitor handle using the Screen.Monitors[x].Handle. Getting the handle using the procedure you describe seems like going in circles.

Anyway, I have used GetMonitorInfo to check that the handle provided by TScreen is valid (see below). It gives the correct size of my secondary monitor.

Therefore, I suspect that the problem lies in ShellExecuteEx.

procedure TForm1.Button3Click(Sender: TObject);
var
  SecondaryMonitor : Cardinal;
  mi : TMonitorInfo;
begin
  // Determine the monitor handle using Delphi Screen
  if Screen.MonitorCount = 1 then
    SecondaryMonitor := 0
  else if Screen.PrimaryMonitor = Screen.Monitors[0] then
    SecondaryMonitor := Screen.Monitors[1].Handle
  else
    SecondaryMonitor := Screen.Monitors[0].Handle;
  // Check that the handle is valid
  mi.cbSize := SizeOf(mi);
  GetMonitorInfo(SecondaryMonitor,@mi);
  ShowMessage(Format('The monitor rect is: %d,%d %d,%d',
    [mi.rcMonitor.Left,mi.rcMonitor.Top,mi.rcMonitor.Right,mi.rcMonitor.Bottom]));
end;

Select allOpen in new window

Is the program you are trying to launch one of yours? Did you write it or do you access to the source code?  The reason I ask is that the application your are trying to launch may have specific settings requiring it to launch in the same screen location everytime (i.e. ScreenCenter).

I have tried many different programs, including a test one that does not set any special positioning, i.e. Position := poDefaultPosOnly.

forgot to mention, after yuo found the handle of the window, use the movewindow function to place it in correct monitor as in my very first link.

I was precisely thinking along the same line of placing myself the window in the desired monitor.

I prefer to use ShellExecute because I have had many problems in the past with CreateProcess. Getting the process ID is easy, enumerating processes. But I have a question? How do I ensure that ShellExecute does not return until the main window has been created? I have noticed that the function returns immediately.

Another issue is getting the main window once I have the process ID. What do you suggest?

How does the main code of your test application look like? Delphi applications have a hidden main window that maybe is positioned on the other monitor instead of the real window. In newer Delphi this problem can be solved by adding "Application.MainFormOnTaskbar := True;" Maybe you/we should test this with a window application created by C++/Delphi without any framework (VCL, MFC, ATL ...).

You can wait for an process until it can process input events by calling WaitForInputIdle (http://msdn.microsoft.com/en-us/library/ms687022(VS.85).aspx)

"Maybe you/we should test this with a window application created by C++/Delphi without any framework (VCL, MFC, ATL ...). "
Sorry, I mean the whole problem! I'll check it in C++ when I have time.

when you want your app to start on a second monitor,
i suppose you want all your forms to open on that same monitor
or where the app is residing at that moment

when you open a secondary form you need to set it to poOwnerFormCenter
and create your forms with passing the form calling it

procedure TForm1.Button1Click(Sender: TObject);
begin
  Form2 := TForm2.Create(Self);
  try
    // do stuff with Form2
  finally
    FreeAndNil(Form2);
  end;
end;

also when autocreating the forms in the dpr
change the owner of the second, third, etc forms from
Application.CreateForm(TForm1, Form1);
Application.CreateForm(TForm2, Form2);

to
Application.CreateForm(TForm1, Form1);
Form2 := TForm2.Create(Form1);

For the initial form i need to look into code at work
I think i solved this issue once

I see from the comments received that I have not expressed myself correctly. My needs are to find a general way to launch ANY application and place it in a secondary monitor.

When I found the new functionality in SellExecuteEx, I thought that this was the correct approach, but I have discovered that it is not.

Therefore, the way to go seems to be:

1) Use ShellExecuteEx to launch the application.
2) Obtain the process ID by enumerating all running processes.
3) Use WaitForInputIdle to wait for the application window to be created.
4) Determine the main window of the application using EnumWindows.
5) Manually move the main window to the secondary monitor using MoveWindow.

I will create a test application and post it here for your comments. But so far, your comments are really helping me to solve this problem. Thank you all very much!

with CreateProcess you have direct access to the process id

var
  ProcessInfo: TProcessInformation;
  StartupInfo: TStartupInfo;
  BatchFile: string; // example: "notepad.exe"

FillChar(StartupInfo, SizeOf(TStartupInfo), 0);
with StartupInfo do
begin
  cb:= SizeOf(TStartupInfo);
  dwFlags:= STARTF_USESHOWWINDOW;
  wShowWindow:= SW_SHOWNORMAL;
end;

{ Execute batch file as separated process }
CreateProcess(PChar(BatchFile), nil, nil, nil, False, NORMAL_PRIORITY_CLASS,
    nil, nil, StartupInfo, ProcessInfo);

see ProcessInfo.hProcess for the processid

Your suggestion helped me a lot. I have not yet been able to make a test that works, but I am in the right track. If I get stuck, I'll post a new question. Thank you very much.

I am working on a complete example, using the suggestions given in your comments. I have not finished it yet but it seems to be the way to go. Thank you all very much.