Article: Q127192
Product(s): Microsoft C Compiler
Version(s): winnt:2.0,2.1,4.0,4.1,5.0
Operating System(s):
Keyword(s): kbole kbnokeyword kbActiveX kbCOMt kbCtrl kbInplaceAct kbMetafile kbMFC kbVC150 kbVC200
Last Modified: 06-MAY-2001
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The information in this article applies to:
- The Microsoft Foundation Classes (MFC), used with:
- Microsoft Visual C++ for Windows, 16-bit edition, versions 1.5, 1.51, 1.52
- Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 4.0, 4.1
- Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0
- Microsoft Visual C++, 32-bit Professional Edition, version 5.0
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SUMMARY
=======
You can use controls, either directly on a CView or from a dialog template on a
CFormView, in an OLE enabled MFC application. However, when the item is embedded
but not active, the controls on these views will not be drawn to the Windows
metafile supplied to the COleServerItem::OnDraw() function. In this case, you
must "draw" the controls manually into the metafile. This article shows you how.
MORE INFORMATION
================
The simplest way to get controls to "draw" in a metafile is to use the same
method the VIEWEX sample uses to draw its CInputView to a printer device
context. VIEWEX's OnPrint routine draws each control as a rectangle, circle,
text, and so on. Override the COleServerItem::OnDraw() function and insert your
code into it. As an example, use the COleServerItem::OnDraw() function listed in
this article; it shows both the VIEWEX code to insert in the OnDraw member
function and the helper function PaintChildWindows() that actually does the
painting of each control.
Sample Code
-----------
/* Compile options needed: Standard
*/
void CMyServerItem::OnDraw(CDC* pDC) // pDC is actually a metafile
{
//BLOCK: Set up scale mode
{
CClientDC dcScreen(NULL);
pDC->SetMapMode(MM_ANISOTROPIC);
// map 1 screen logical inch to 1 printer (/output) logical inch
pDC->SetWindowExt(dcScreen.GetDeviceCaps(LOGPIXELSX),
dcScreen.GetDeviceCaps(LOGPIXELSX));
pDC->SetViewportExt(pDC->GetDeviceCaps(LOGPIXELSX),
pDC->GetDeviceCaps(LOGPIXELSX));
}
// we must also offset the window positions relative to the scroll
// offset
// We cheat here since some controls do not paint if they are
// invisible, so we temporary make set the appropriate visible bits
// during preview mode so the controls think they are visible even
// though they aren't.
HWND hWndCheatVisible = NULL;
if (!IsWindowVisible())
{
// walk up to the top until we find the invisible window
for (HWND hWnd = m_hWnd;
hWnd != NULL; hWnd = ::GetParent(hWnd))
{
ASSERT(hWnd != NULL);
DWORD dwStyle = ::GetWindowLong(hWnd, GWL_STYLE);
if ((dwStyle & WS_VISIBLE) == 0)
{
::SetWindowLong(hWnd, GWL_STYLE, dwStyle | WS_VISIBLE);
hWndCheatVisible = hWnd;
break;
}
}
ASSERT(hWndCheatVisible != NULL);
}
CPen pen(PS_SOLID, 1, RGB(0,0,0)); // solid black pen
CPen* pOldPen = pDC->SelectObject(&pen);
ASSERT(pDC->GetWindowOrg() == CPoint(0,0));
CRect pRect = new CRect(-50,-50,600,600);
PaintChildWindows(m_hWnd, pDC, GetDeviceScrollPosition());
ASSERT(pDC->GetWindowOrg() == CPoint(0,0));
pDC->SelectObject(pOldPen);
if (hWndCheatVisible != NULL)
::SetWindowLong(hWndCheatVisible, GWL_STYLE,
::GetWindowLong(hWndCheatVisible, GWL_STYLE) &~ WS_VISIBLE);
}
void CMyServerItem::PaintChildWindows(HWND hWndParent,
CDC* pDC, CPoint ptOffset)
{
for (HWND hWndChild = ::GetTopWindow(hWndParent);
hWndChild != NULL;
hWndChild = ::GetNextWindow(hWndChild, GW_HWNDNEXT))
{
CRect rect;
::GetWindowRect(hWndChild, rect); // wnd rect in screen coords
ScreenToClient(&rect); // relative to this view
HDC hdcOut = pDC->m_hDC;
#ifdef _DEBUG
CPoint pt = pDC->GetWindowOrg();
ASSERT(pt.x == 0 && pt.y == 0);
#endif
DWORD dwStyle = ::GetWindowLong(hWndChild, GWL_STYLE);
if (dwStyle & (WS_HSCROLL|WS_VSCROLL))
{
TRACE("Warning: printing control with scrollbars not
supported\n");
}
if (dwStyle & WS_BORDER)
{
// the only case we special case - manually drawn border
::Rectangle(hdcOut, rect.left, rect.top, rect.right,
rect.bottom);
rect.InflateRect(-1,-1); // 1 logical pixel
}
pDC->SaveDC();
{
CPoint pt(ptOffset.x + rect.left, ptOffset.y + rect.top);
pDC->LPtoDP(&pt);
pDC->OffsetViewportOrg(pt.x, pt.y);
// set the viewport origin so that the window origin
// can be changed by the control
// draw it using a non-virtual HDC
::SendMessage(hWndChild, WM_PAINT, (WPARAM)hdcOut, 0L);
}
pDC->RestoreDC(-1);
if (::GetTopWindow(hWndChild) != NULL)
PaintChildWindows(hWndChild, pDC, ptOffset);
}
}
Additional query words: mfc ole inplace embed
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Keywords : kbole kbnokeyword kbActiveX kbCOMt kbCtrl kbInplaceAct kbMetafile kbMFC kbVC150 kbVC200 kbVC400 kbVC500 kbGrpDSMFCATL
Technology : kbAudDeveloper kbMFC
Version : winnt:2.0,2.1,4.0,4.1,5.0
Hardware : x86
Issue type : kbhowto
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