PRB: SetItemRects Causes Server to Change Zoom Factor

WINDOWS   | WINDOWS NT

The information in this article applies to:

• The Microsoft Foundation Classes (MFC), included with:

      - Microsoft Visual C++ for Windows, versions 1.50 and 1.51
      - Microsoft Visual C++, 32-bit Edition, versions 2.0 and 2.1
  

SYMPTOMS

Calling COleClientItem::SetItemRects() causes the server to change its zoom-factor.

RESOLUTION

In some cases, you may find it advantageous to have a container change the area provided to an in-place active object without changing the zoom factor of the object. To do this, have the container first set the object's extents by calling COleClientItem::SetExtent and then set the in-place item's window size by calling COleClientItem::SetItemRects.

STATUS

This behavior is by design.

MORE INFORMATION

COleClientItem::SetItemRects() calls IOleInPlaceObject::SetObjectRects() and passes its parameters. The following is the description of IOleInPlaceObject::SetObjectRects() in Volume 2 of the OLE2 Programmer's Reference:

   The object should compare its width and height with those
   provided by its container (conveyed through lprcPosRect).
   If the comparison does not result in a match, the container
   is applying either scaling or zooming to the object.
   The object must then decide whether it should continue the
   in-place editing in the scale/zoom mode or deactivate."

The following sample code demonstrates this technique. It assumes that CMyClientItem is derived from COleClientItem and that rect has coordinates specified with respect to the view which contains the object. It returns true if SetItemRects was successful.

Sample Code

BOOL CMyClientItem::MySetObjectRects(CRect &rect) {

  ASSERT_VALID(this);
  ASSERT(m_lpObject != NULL);
  ASSERT(IsInPlaceActive());

  // get the size of this new rectangle
  CSize size = rect.Size();

  // now convert this size to HIMETRIC units
  size.cx = XformHeightInPixelsToHimetric(NULL, size.cx);
  size.cy = XformWidthInPixelsToHimetric(NULL, size.cy);

  // use this size to set the extent of the object
  SetExtent(size);

  // finally set the new size for the in-place window
  return SetItemRects(rect, rect);