Can't get screen/client coordinates right

Question

Hi

A small class CFrameGroup, derived from CStatic, get's created with parent window (the application dialog) and an IDC_STATIC_xxx of a group box. The CFrameGroup object then draws a "highlight" frame inside the groupbox to get the users attention of that particular groupbox.

I can't get the position of that frame right! 

Code of CFrameGroup class:

IMPLEMENT_DYNAMIC(CFrameGroup, CStatic)

CFrameGroup::CFrameGroup( )
	: mbHighlighted( FALSE )
{
}

CFrameGroup::~CFrameGroup()
{
}


BEGIN_MESSAGE_MAP(CFrameGroup, CStatic)
	ON_WM_PAINT()
END_MESSAGE_MAP()

// CFrameGroup message handlers

void CFrameGroup::OnPaint()
{
	CPaintDC dc(this); // device context for painting
	CRect cRect;
    CPen penBlack;

	GetRect( cRect );

	if( mbHighlighted )
		penBlack.CreatePen(PS_SOLID, 2, RGB(0xff, 0, 0));
	else
		penBlack.CreatePen( PS_SOLID, 2, RGB( 0x00, 0x00, 0x00 ));

    CPen* pOldPen = dc.SelectObject(&penBlack);

	dc.MoveTo( cRect.left, cRect.top );
	dc.LineTo( cRect.right, cRect.top );
	dc.LineTo( cRect.right, cRect.bottom );
	dc.LineTo( cRect.left, cRect.bottom );
	dc.LineTo( cRect.left, cRect.top + 1 );

     dc.SelectObject(pOldPen);
}

void CFrameGroup::SetHighlighted( BOOL highlighted )
{
	mbHighlighted = highlighted;
	Invalidate();
}

BOOL CFrameGroup::GetHighlighted()
{
	return mbHighlighted;
}


BOOL CFrameGroup::Create( UINT groupBoxId, CWnd *parent )
{
	CRect cRect;
	mGroupBoxId = groupBoxId;
	mpParent = parent;
	mpGroupBox = parent->GetDlgItem( groupBoxId );
	GetRect( cRect );

	return CStatic::Create( _T("STATIC"), WS_CHILD | WS_VISIBLE, cRect, parent );
}

void CFrameGroup::GetRect( CRect& rect )
{
	mpGroupBox->GetWindowRect( rect );
	mpParent->ScreenToClient( rect );
	rect.DeflateRect( 5, 12, 5, 5 );
}

From the application dialogue the the CFrameGroup objects are created in OnInitDialogue

	mFrameG1.Create( IDC_STATIC_1, this );
	mFrameG2.Create( IDC_STATIC_2, this );

Best Regards

Tage



Answer 1

It looks like your question belongs in the MFC forum:

http://social.msdn.microsoft.com/Forums/en-US/vcmfcatl/threads

Your problem might be that you are saving the results of GetDlgItem in a member variable (mpGroupBox).

GetDlgItem returns a temporary pointer that should not be saved. (Just call GetDlgItem in any function where you need its result.)