PRB: Owner-Drawn ListView Control in 68K Application Crashes Macintosh

MORE INFORMATION

The workaround involves setting the itemHeight data member of the LPMEASUREITEMSTRUCT structure pointer before the control is displayed. This can be done only in the parent window's WM_MEASUREITEM handler. It is not necessary to initially create the control without the WS_VISIBLE flag.

The code below shows an example for an owner-drawn ListView control in a form view. The default height of a ListView control item on the Macintosh is 14 pixels.

BEGIN_MESSAGE_MAP(CMyView, CFormView)
    ON_WM_MEASUREITEM()
    ...
END_MESSAGE_MAP()

// WM_MEASUREITEM is sent to parent of list control
void CMyView::OnMeasureItem(int nIDCtl,
    LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
    if (nIDCtl == IDC_LIST1) {

        // Calculate appropriate font height.
        int newHeight = 0;
        CFont* pFont = (CFont*)GetFont();
        if (pFont) {
            LOGFONT lf;
            pFont->GetLogFont(&lf);
            newHeight = (lf.lfHeight > 0) ? lf.lfHeight : -lf.lfHeight;
        }

        // Set new itemHeight, use 14 as default height.
        lpMeasureItemStruct->itemHeight = newHeight ? newHeight : 14;
    }
    CFormView::OnMeasureItem(nIDCtl, lpMeasureItemStruct);
}
				

IDC_LIST1 is the ID of the owner-drawn ListView control.

NOTE: This problem does NOT appear on Visual C++ for the Macintosh version 4.0.