Groups > comp.lang.pascal.delphi.misc > #136

Re: How to clear transparent Canvas?

Path	csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!gegeweb.42!gegeweb.eu!nntpfeed.proxad.net!feeder1-1.proxad.net!proxad.net!feeder1-2.proxad.net!74.125.46.80.MISMATCH!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
From	88888 Dihedral <dihedral88888@googlemail.com>
Newsgroups	comp.lang.pascal.delphi.misc
Subject	Re: How to clear transparent Canvas?
Date	Tue, 27 Dec 2011 12:20:29 -0800 (PST)
Organization	http://groups.google.com
Lines	53
Message-ID	<21491746.601.1325017230000.JavaMail.geo-discussion-forums@prmu8> (permalink)
References	<4ef8a45d$0$1200$65785112@news.neostrada.pl> <Ke3Kq.18986$aW6.6491@newsfe09.iad> <4ef8f5cd$0$1208$65785112@news.neostrada.pl> <c%9Kq.41981$cG.9336@newsfe14.iad>
Reply-To	comp.lang.pascal.delphi.misc@googlegroups.com
NNTP-Posting-Host	1.168.132.181
Mime-Version	1.0
Content-Type	text/plain; charset=UTF-8
Content-Transfer-Encoding	quoted-printable
X-Trace	posting.google.com 1325017230 1245 127.0.0.1 (27 Dec 2011 20:20:30 GMT)
X-Complaints-To	groups-abuse@google.com
NNTP-Posting-Date	Tue, 27 Dec 2011 20:20:30 +0000 (UTC)
In-Reply-To	<c%9Kq.41981$cG.9336@newsfe14.iad>
Complaints-To	groups-abuse@google.com
Injection-Info	glegroupsg2000goo.googlegroups.com; posting-host=1.168.132.181; posting-account=5JdMBQoAAABHnS4mjpqEzxnmWtgiiVNw
User-Agent	G2/1.0
X-Google-Web-Client	true
Xref	x330-a1.tempe.blueboxinc.net comp.lang.pascal.delphi.misc:136

Show key headers only | View raw

Jamie於 2011年12月27日星期二UTC+8上午10時27分52秒寫道：
> aaaa wrote:
> > I know that and I wonder how to do this most efficiently.
> > 
> > When I do:
> > MyComponent.Visible := False;
> > MyComponent.Visible := True;
> > everything that is behind my component gets repainted and then my 
> > component's Paint() method gets called and everything looks great.
> > And my component is transparent because I can see the labels and other 
> > controls placed behind it.
> > 
> > The thing is- what exactly is this "Visible" doing...?
> > 
> > The idea of saving the snapshop as TBitmap is nice- I think it should 
> > make "clearing" faster. After all nothing will change behind my 
> > component as long as it is Focused and when it looses Focus I can resave 
> > the snapshop.
> > 
> > How to get the snapshop in the best way? Should I iterate all controls 
> > of my component's parent and invoke their WM_PAINT somehow onto my 
> > snapshot's TBitmap? Or is there any easier way?
> > 
> > Best regards,
> > A
>   You could wedge into the Paint Method of each control but wouldn't
> be easier to simply create a control of your own that will do this for you?
>    You simply start with an existing control and build on that.
> 
>   Its not clear exactly what you're trying to do yet..
> 
>   P.S.
> 
>     If you have not made a control yet, maybe this is a good time to
> learn.
> 
>   Jamie

In Delphie the object in the display image  of a Window is different 
from the image.scanline[j] as far as I know. 

The container and the content are separate objects  to be programmed 
by the programmer.

Back to comp.lang.pascal.delphi.misc | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

How to clear transparent Canvas? "aaaa" <aaaa@aaaaaaaaaaaaaaaaaaa.com> - 2011-12-26 17:44 +0100
  Re: How to clear transparent Canvas? Jamie <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> - 2011-12-26 13:47 -0500
    Re: How to clear transparent Canvas? "aaaa" <aaaa@aaaaaaaaaaaaaaaaaaa.com> - 2011-12-26 23:31 +0100
      Re: How to clear transparent Canvas? Jamie <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> - 2011-12-26 21:27 -0500
        Re: How to clear transparent Canvas? 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-27 12:20 -0800
  Re: How to clear transparent Canvas? battles <battles@mailinator.com> - 2011-12-27 16:59 -0800

csiph-web