asked on

refreshing a form while it's busy

I'm trying to make my program window stay painted even if another screen is activated and displayed in front of it. This program runs a bunch of external programs. I also have a duration to show how long it's been running. My problem is that while I'm waiting for the process to complete, I am trying to make the program refresh the screen so that if I move a window over it, I can still go back to the screen and see the program status. I don't feel all that confident in my understanding of the difference between update, refresh, and repaint, or what it means for an object to be invalid. I have tried a bunch of combinations, but none of them work. Here's what I have for the loop that I use to wait for the running process to complete. Thanks in advance for your assistance.

repeat
sleep( 2000 );
lblTime.Caption := FormatDateTime('nn:ss',Time - StartTime);
FrmMain.Refresh;
GetExitCodeProcess(ProcessInfo.hProcess,Resultado);
Result := Resultado;
until (Result <> STILL_ACTIVE) or Application.Terminated;

ASKER CERTIFIED SOLUTION

DaFox

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Member_2_248744

hello bnac, , you might use a different code to wait for your other process to finish

if FileExists(ProcessInfo.lpFile) and ShellExecuteEx(@ProcessInfo) then
begin
while WaitForSingleObject(ProcessInfo.hProcess, 100) <> WAIT_OBJECT_0 do
begin
lblTime.Caption := FormatDateTime('nn:ss',Time - StartTime);
// if you have Application.ProcessMessages you will NOT need the Refresh
Application.ProcessMessages;
end;
end else
ShowMessage(SysErrorMessage(GetLastError));

bnac

ASKER

Markus,

I added Application.ProcessMessages, and dropped the sleep time to 250, and it's working exactly as I expected. Taking out the sleep time caused the program to go from 0% CPU utilization to 90%. Thanks for your amazingly quick response!

Matt

bnac

ASKER

Slick, Thanks for your reply. I'm going to keep the wait loop that I have though, because I've used it in a few apps, and it works well.