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Win32 API question

fh1
fh1 asked
on
Medium Priority
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Last Modified: 2010-04-06
I have the handle of an application running outside of my delphi 3.0 application. How can I check when that application is finished from inside of my delphi application?
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There are many methods to do that and here is one of them,,,,,

In OnTimer()
var
  H : HWND;
begin
  H := FindWindow(nil, 'Untitled - Notepad');
  if H = 0 then
  begin
    ShowMessage('The application has already finished!');
    //Do your code here.....
    Timer1.Enabled := False;//If it's only for once..otherwise don't disable the timer...
  end;
end;

Regards,
Viktor Ivanov

fh1

Author

Commented:
To Viktor Ivanov:
I don't have the name of the window, but I have the handle of it.
Here is the second method and more official, with a little more code....
Params -
   Filename - the filename of the app to execute and wait for.....
    Visibility - SW_SHOW, SW_HIDE, SW_SHOWNORMAL........
--------------
How do I execute a program and have my code wait until it is finished?

function WinExecAndWait32(FileName:String; Visibility : integer):integer;
var
  zAppName:array[0..512] of char;
  zCurDir:array[0..255] of char;
  WorkDir:String;
  StartupInfo:TStartupInfo;
  ProcessInfo:TProcessInformation;
begin
  StrPCopy(zAppName,FileName);
  GetDir(0,WorkDir);
  StrPCopy(zCurDir,WorkDir);
  FillChar(StartupInfo,Sizeof(StartupInfo),#0);
  StartupInfo.cb := Sizeof(StartupInfo);

  StartupInfo.dwFlags := STARTF_USESHOWWINDOW;
  StartupInfo.wShowWindow := Visibility;
  if not CreateProcess(nil,
    zAppName,                      { pointer to command line string }
    nil,                           { pointer to process security attributes }
    nil,                           { pointer to thread security attributes }
    false,                         { handle inheritance flag }
    CREATE_NEW_CONSOLE or          { creation flags }
    NORMAL_PRIORITY_CLASS,
    nil,                           { pointer to new environment block }
    nil,                           { pointer to current directory name }
    StartupInfo,                   { pointer to STARTUPINFO }
    ProcessInfo) then Result := -1 { pointer to PROCESS_INF }

  else begin
    WaitforSingleObject(ProcessInfo.hProcess,INFINITE);
    GetExitCodeProcess(ProcessInfo.hProcess,Result);
  end;
end;
------------
Regards,
Viktor Ivanov
If you want use the method I just gave otherwise if you want to use the first method here is how if you have the handle.....

var
  H : HWND;
begin
  H := //the handle you already know of your application.....
  if H = 0 then
  begin
    ShowMessage('The app is already running');
    //Do you job here.....
  end;
end;
oopssss....see the line that says ShowMessage('The app is already running');...this is suppose to be ShowMessage('The app is already finished');
sorry for the wrong code ;)

Regards,
Viktor Ivanov
fh1

Author

Commented:
Since I only know the handle of the window, I have to find the name of the window and then check in a loop if the handle of this window become zero.
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