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Hello,



I have a CDialog derived object that contains two child windows. I

implement splitter-like functionality (without using CSplitterWnd) and

have everything working correctly.



Now, I want to add a "track bar" so when the user drags to resize, he

sees where the split will end up being. I use code like this:



CDC *pDC = GetDC()



if(pDC)

{

CBrush *pBrush = pDC->GetHalftoneBrush();



if(pBrush)

pBrush = pDC->SelectObject(pBrush);



pDC->PatBlt(rc.left, rc.top, rc.Width(),

rc.Height(), PATINVERT);



if(pBrush)

pDC->SelectObject(pBrush);



ReleaseDC(pDC);

}



This *seems* to work OK, except the drawing (understandably) takes

place *under* the child windows, and the bar is, therefore, occluded.



Any ideas on how I can make the tracking bar paint on top of child windows?



-n


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Nikolaos D. Bougalis wrote:

You need to remove WS_CLIPCHILDREN from the parent wnd. If that screws

up the dialog controls then you would need an underlying splitter window

as the parent of the panes, just like CSplitterWnd uses.



--

Scott McPhillips [VC++ MVP]



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Scott McPhillips [MVP] wrote:



Ahh!!! WS_CLIPCHILDREN it is!!! Silly me!



And here I was about to resort to using CWindowDC and doing all sorts

of magic to map the client-space rectangle to window-space.



Thanks!



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Since the rest has been answered, the question is why are you doing something as

complicated as declaring a CDC * and doing GetDC(), when

CClientDC dc(this);

works just fine?

joe



On Thu, 24 Jun 2004 13:09:54 -0700, "Nikolaos D. Bougalis" <nikb@webmaster.com>wrote:



Joseph M. Newcomer [MVP]

email: newcomer@flounder.com

Web: www.flounder.com">www.flounder.com

MVP Tips: www.flounder.com/mvp_tips.htm">www.flounder.com/mvp_tips.htm

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Joseph M. Newcomer wrote:



I have a memory DC wrapper class; You declare an instance of it, and

pass it a pointer to a DC. You do all the drawing to the memory DC, and

then, it blits itself to the screen and releases the DC you passed to it.



I didn't copy code verbatim, but I didn't want to significantly change

it either, so "GetDC" stayed (in lieu of WMemoryDC dc(GetDC())) and a

ReleaseDC was added to avoid comments about the DC not being released.



Granted, I could (and probably should) make WMemoryDC get a CWnd or an

HWND and deal with all the DC stuff internally.



-n





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