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nafa2221

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Window

How do I check to see if a window is active by its title. Lets say its iternet explorer and itnernet explorers title bar contains 'Microsoft Internet Explorer'...thanks
Avatar of DrDelphi
DrDelphi

var winhandle:Thandle;
    WinCaption:array[0..255] of char;
begin
   WinHandle:=GetForegroundwindow;
   GetwindowText   (WinHandle,WinCaption,254);
   showmessage(WinCaption);




Avatar of nafa2221

ASKER

I found the following function to find a window by title, but can you review the code and give me an example? Thanks.

function FindWindowChildByTitle( const ParentWnd : HWnd; const Title : string) : HWnd;
var
W1st, Wth : HWnd;
WinName : PChar;
begin
Result:=0;
W1st:=GetWindow(ParentWnd, GW_CHILD);
if W1st <> 0 then begin
WinName:=StrAlloc(256);
Wth:=W1st;
repeat
GetWindowText(Wth,WinName,255);
if StrPas(WinName) = Title then begin
Result:=Wth;
break;
end;
Wth:=GetNextWindow(Wth, GW_HWNDNEXT);
until (Wth = 0)or(Wth = W1st);
StrDispose(WinName);
end;
end;
This is not what you asked for, this function presumes that you know the parent HWND. I have a good example of finding a window's hwnd on my webpage, if you want to take a look. I also have a fairly new component that I wrote called TWindowWorks which should help you. WWW.DrDelphi.Com

Good luck!!


I know the parent HWND its "AOL Frame25", and the title is "America  Online". I am writeing a program for my cousin that keeps him on AOL. Also...dont even say I should do this in VB cuz I will slap you ;] Thanks
Hello,
look at the following unit.
this should work...
you can't make the test by clicking of a button because your application
will have the focus. Replace Form1
with what you want. Let me know if it's working or not.
I tested it and it is...

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
    btnButton1: TButton;
    procedure btnButton1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  fWindowClass: string;
  fWindowCaption: string;

implementation

{$R *.DFM}

function getChildWinHandle(WinHandle: THandle; FoundWindow: PHandle): BOOL; stdcall;
var
  Buffer: array[0..50] of Char;
begin
  Result := True;
  //  GetClassName(WinHandle, Buffer, SizeOf(Buffer) - 1);
  //  if pos(PChar(fWindowClass), Buffer) <> 0 then
  //  begin
  //    GetWindowText(WinHandle, Buffer, SizeOf(Buffer) - 1);
  //    if Pos(fWindowCaption, Buffer) <> 0 then
  //    begin
  //      FoundWindow^ := WinHandle;
  //      Result := False;
  //    end;
  //  end;
  GetWindowText(WinHandle, Buffer, SizeOf(Buffer) - 1);
  if Pos(fWindowCaption, Buffer) <> 0 then
  begin
    FoundWindow^ := WinHandle;
    Result := False;
  end;
end;

function getWindowHandle(WindowCaption: string; WindowClass: string): THandle;
begin
  fWindowCaption := WindowCaption;
  fWindowClass := WindowClass;
  result := 0;
  EnumWindows(@getChildWinHandle, Integer(@result));
end;

function isContinuusRunning: THandle;
begin
  result := getWindowHandle('Form1', '');
end;

procedure TForm1.btnButton1Click(Sender: TObject);
var
  cMainWindow: THandle;
  wp: TWindowPlacement;
begin
  cMainWindow := isContinuusRunning;

  GetWindowPlacement(cMainWindow, @wp);
  showmessage(inttostr(wp.showCmd));
  if wp.showCmd = SW_SHOWNORMAL then
    showmessage('form is visible')
  else
    showmessage('form is not visible');
end;

end.
use one of those parameters to test the state of the program you want.
because it's not laways sw_shownormal:
found in windows.pas

 SW_HIDE = 0;
  {$EXTERNALSYM SW_SHOWNORMAL}
  SW_SHOWNORMAL = 1;
  {$EXTERNALSYM SW_NORMAL}
  SW_NORMAL = 1;
  {$EXTERNALSYM SW_SHOWMINIMIZED}
  SW_SHOWMINIMIZED = 2;
  {$EXTERNALSYM SW_SHOWMAXIMIZED}
  SW_SHOWMAXIMIZED = 3;
  {$EXTERNALSYM SW_MAXIMIZE}
  SW_MAXIMIZE = 3;
  {$EXTERNALSYM SW_SHOWNOACTIVATE}
  SW_SHOWNOACTIVATE = 4;
  {$EXTERNALSYM SW_SHOW}
  SW_SHOW = 5;
  {$EXTERNALSYM SW_MINIMIZE}
  SW_MINIMIZE = 6;
  {$EXTERNALSYM SW_SHOWMINNOACTIVE}
  SW_SHOWMINNOACTIVE = 7;
  {$EXTERNALSYM SW_SHOWNA}
  SW_SHOWNA = 8;
  {$EXTERNALSYM SW_RESTORE}
  SW_RESTORE = 9;
  {$EXTERNALSYM SW_SHOWDEFAULT}
  SW_SHOWDEFAULT = 10;
  {$EXTERNALSYM SW_MAX}
  SW_MAX = 10;
Can u give me an example that will find to see if the window with the title America Online is running? Thanks
ASKER CERTIFIED SOLUTION
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Tussin
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Let's try again :
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
    btnButton1: TButton;
    procedure btnButton1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  fWindowClass: string;
  fWindowCaption: string;

implementation

{$R *.DFM}

function getChildWinHandle(WinHandle: THandle; FoundWindow: PHandle): BOOL; stdcall;
var
  Buffer: array[0..50] of Char;
begin
  Result := True;
  GetWindowText(WinHandle, Buffer, SizeOf(Buffer) - 1);
  if Pos(fWindowCaption, Buffer) <> 0 then
  begin
    FoundWindow^ := WinHandle;
    Result := False;
  end;
end;

function getWindowHandle(WindowCaption: string; WindowClass: string): THandle;
begin
  fWindowCaption := WindowCaption;
  fWindowClass := WindowClass;
  result := 0;
  EnumWindows(@getChildWinHandle, Integer(@result));
end;

//finds the handle of the window
function isAOLRunning: THandle;
begin
  result := getWindowHandle('America  Online', '');
end;

procedure TForm1.btnButton1Click(Sender: TObject);
var
  cMainWindow: THandle;
  wp: TWindowPlacement;
begin
  cMainWindow := isAOLRunning;

  if cMainWindow = 0 then
  begin
    showmessage('AOL is not running..');
    exit;
  end;

  //this part is for checking the state of the running app
  GetWindowPlacement(cMainWindow, @wp);

  if wp.showCmd = SW_SHOWNORMAL then
    showmessage('AOL is open')
  else
    showmessage('AOL is closed '+intToStr(wp.showCmd));
end;

end.
Tussin, you only check if the form exists.
Not if it is active ;)
well, i guess that can be done with a few lines of code. may be this is already in the answers provided. i didn't check them all.  (They appeared too long and i didn't have the time. sorry folks.)


//declare global variables in your unit.
const partialtitle = 'partial title of the window you want to find';
var HWND_aol : HWND;

function ewp(h: HWND; var l : longint):boolean;stdcall;

var  c : array[0..255] of char;

begin
GetWindowText(h, @c, 255);
if pos(partialtitle, StrPas(@c)) <> 0 then
    begin;
    HWND_AOL := h;
    Result := false; //stop if window found.
    end
else Result := true;
end;


//in your code...
begin;
hwnd_aol := 0;
enumWindows(@ewp, 0); //find the handle of aol
if HWND_aol <> 0 then
  begin;
  if (GetActiveWindow = hwnd_AOL) then
     ShowMessage('AOL is active Window')
  else   ShowMessage('AOL is running, but is not the active Window');
  end
else  ShowMessage('AOL is NOT runningn');
end;
well, i guess that can be done with a few lines of code. may be this is already in the answers provided. i didn't check them all.  (They appeared too long and i didn't have the time. sorry folks.)


//declare global variables in your unit.
const partialtitle = 'partial title of the window you want to find';
var HWND_aol : HWND;

function ewp(h: HWND; var l : longint):boolean;stdcall;

var  c : array[0..255] of char;

begin
GetWindowText(h, @c, 255);
if pos(partialtitle, StrPas(@c)) <> 0 then
    begin;
    HWND_AOL := h;
    Result := false; //stop if window found.
    end
else Result := true;
end;


//in your code...
begin;
hwnd_aol := 0;
enumWindows(@ewp, 0); //find the handle of aol
if HWND_aol <> 0 then
  begin;
  if (GetActiveWindow = hwnd_AOL) then
     ShowMessage('AOL is active Window')
  else   ShowMessage('AOL is running, but is not the active Window');
  end
else  ShowMessage('AOL is NOT runningn');
end;
well, after typing it, my comments looks pretty long as well. so may be it ain't an improvement after all.
To keep the connection, can't you just have a timer, which after every 300000 milliseconds does a:

  ShellExecute( 0, 'ping www.altavista.com', nil, nil, SW_HIDE ) ;

Or something...

Dont understand AOL though, so I am probably wrong :O)

Tim.