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From: cmcmanis%pepper@Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga
Subject: Re: Need help rendering Gadgets
Message-ID: <34626@sun.uucp>
Date: Mon, 23-Nov-87 14:58:02 EST
Article-I.D.: sun.34626
Posted: Mon Nov 23 14:58:02 1987
Date-Received: Thu, 26-Nov-87 07:11:42 EST
References: <1980@antique.UUCP>
Sender: news@sun.uucp
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 34

Yes, BOOLEAN gadgets with nothing but IntuiText and Border structures
have serious problems under intuition. The only truely useful BOOLEAN
gadget is one with Imagery. So the workaround/answer is to build a 
little baby bitmap and render your intuitext/border into it, and then
munge it into an Image structure and pass that to intuition. Also
On/OffGadget does not work as you might expect and can cause flashing
of your Boolean gadgets. It is better (and certainly more efficient)
to set or reset the GADGDISABLED flag and then call RefreshGList()
with only that gadget. With neither an Image or Border struct some
of Intuitions routines my get confused into believing that this is
an Invisible gadget and thus the lack of response from OnGadget(). 

As for removing gadgets from the screen, no support at all. AddGadget()
and RemoveGadget() simply manipulate the Window's gadget list. You can
write one though really easily, it goes something like :

void
EraseGadget(w,g)

struct Window	*w;
struct Gadget	*g;

{
  SetAPen(w->RastPort,w->BgPen);
  RectFill(w->RastPort,g->LeftEdge,g->TopEdge,
		g->LeftEdge+g->Width,g->TopEdge+g->Height);
}

Or you could pass in a color you wanted to use instead of the windows
background pen. 

--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.