Game Initialization and Shutdown - Game Coding Complete - page 150

{

FlashWindow( GetHwnd(), false );
break;

}

}
else
{

now = timeGetTime();
DWORD timeSpan = now > then ? (now - then) : (then - now);
if ( timeSpan > 1000 )
{

then = now;
FlashWindow( GetHwnd(), true );

}

}

}

}

}
Doing this is a little tricky. You basically have to run your own message pump in a
tight loop and swallow the WM_SYSCOMMAND and SC_CLOSE messages until your
game isn

'

t minimized anymore, all the while calling FlashWindow() at regular time

intervals.

Forcing Modal Dialog Boxes to Close
When your game is closed by something external, such as a power down due to a low
battery condition, you might have some tricky cleanup to do if you are inside one of
your modal dialogs we ' ll be discussing in Chapter 9, “ Programming Input Devices. ”
Since you are running a special version of the message pump, the “ real ” message

pump won t get the message.

The solution lies in forcing the modal dialog to close with its default answer and then
resending the WM_SYSCOMMAND with the SC_CLOSE parameter back into the message
pump. If you happen to have nested dialogs up, this will still work because each dia-
log will get a forced close until the normal message pump can process the close
message.
Here

'

' s the pseudo-code for the code inside the SC_CLOSE message handler:

If (you want to prompt the user)
{

If (m_bQuitRequested)
Return early - user is spamming Alt-F4