procedure
SendKeys(WinHandle:Hwnd;Buffer:String);

var
I: Integer;
W: Word;
D: DWORD;
P: ^DWORD;

begin
P:=@D;
SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT,0,P,0);
if IsIconic(WinHandle) then
ShowWindow(WinHandle,SW_RESTORE);
SetForegroundWindow(WinHandle);
For I := 1 to Length(Buffer) do
begin
W:=VkKeyScan(Buffer[i]);
keybd_event(w,0,0,0);
keybd_event(w,0,KEYEVENTF_KEYUP,0);
end;
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT,0,nil,0);
SetForegroundWindow(ParentHwnd);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT,D,nil,0);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
WinExec('notepad.exe',SW_NORMAL);
SendKeys(FindWindowEx(FindWindow('Notepad','Untitled -
Notepad'),0,'Edit',''),'Your Text Here');
end;