CustomDraw remains in PrePaint drawstage

Question

I am facing some troubles when processing the NM_CUSTOMDRAW message on 64 bit machines. We have an CListCtrl derived class with a CHeaderCtrl derived header (linked via PreSubclassWindow).

In the CHeader derived class we do some custom painting. This works for a 32bit build. But when I build a 64bit variant the drawstage remains CDDS_PREPAINT.

So I am posting here to get some help on this issue. I tried a lot of combinations of result values, drawstage handling in the OnCustomDraw ... but all of them still receive only the CDDS_PREPAINT drawstage.

Here you have my current testcode for OnCustomDraw:

void CListViewCtrlExHeader::OnCustomDraw(NMHDR* pNMHDR, LRESULT* pResult)
{
    LPNMCUSTOMDRAW  lpnmcd = (LPNMCUSTOMDRAW )pNMHDR; 
    *pResult = CDRF_DODEFAULT; 
    if (lpnmcd) 
    { 
        switch (lpnmcd->dwDrawStage) 
        { 
            case CDDS_PREERASE: 
            { 
                    TRACE(_T("CDDS_PREERASE\n")); 
                    *pResult |= CDRF_NOTIFYPOSTERASE; 
            break; 
            } 
            case CDDS_POSTERASE: 
            { 
                    TRACE(_T("CDDS_POSTERASE\n")); 
            break; 
            } 
            case CDDS_PREPAINT: 
            { 
                    TRACE(_T("CDDS_PREPAINT\n")); 
                    *pResult |= CDRF_NOTIFYPOSTPAINT; 
            break; 
            } 
            case CDDS_POSTPAINT: 
            { 
                    TRACE(_T("CDDS_POSTPAINT\n"));
                    break; 
            } 
            default: 
            { 
                    TRACE(_T("CDDS_OTHER\n")); 
                    break; 
            } 
        } 
    } 
}

The only purpose of this header ctrl is painting above the default painting, so there is not much code in there. The painting of the CListCtrl derived class does not not do anything special, it lets CListCtrl handle the OnPaint message. The CListCtrl derived class does contain an OnCustomDraw section. But since it works on 32 bit, I doubt the problems should be searched there, on the other hand I mention it since I am out of options...

I found some posts with similar issues (only64 bit or drawstage remains) but none of them worked for me. One of these solutions was an incorrect definition of NMCUSTOMDRAW struct, but mine is the MFC version and no complaints found for 64bit for it. Another was that result did not get processed because of where the component was placed, but then it should not work on 32 bit too. Other solutions are specific for handling the OnCustomDraw messages and results, but that seems to be fine for my testcode...

Kind Regards,

Kevin

CustomDraw remains in PrePaint drawstage

0 Answers0