CListCtrl DrawItem自绘闪烁问题

我扩展了一个CListCtrl类，通过DrawItem来绘制单元格，进度条的功能，现在代码实现了，但是会有闪烁，拉动滚动条的时候会闪烁，更新单元格还是会闪烁，请问大侠们，我哪里写错了么？我通过双缓冲来绘制背景代码如下：
BOOL CListCtrlex::OnEraseBkgnd(CDC* pDC)
{
// TODO: 在此添加消息处理程序代码和/或调用默认值
CRect rc;
GetWindowRect(&rc);
CDC CMDC;
CMDC.CreateCompatibleDC(NULL);
 
CBitmap bmp; bmp.CreateCompatibleBitmap(pDC,rc.Width(),rc.Height()); CBitmap * oldbmp  =CMDC.SelectObject(&bmp);
    BITMAP bm;
bmp.GetBitmap(&bm);
CMDC.FillSolidRect(0,0,rc.Width(),rc.Height(),m_refdefbkColor);
 
pDC->StretchBlt(0,0,rc.Width(),rc.Height(),&CMDC,0,0,bm.bmWidth,bm.bmHeight,SRCCOPY);
CMDC.SelectObject(oldbmp);
bmp.DeleteObject();
CMDC.DeleteDC(); return  TRUE;// CListCtrl::OnEraseBkgnd(pDC);
}DrawItem函数中绘制单元格 代码如下：
void CListCtrlex::DrawItem(LPDRAWITEMSTRUCT lpItemStruct)
{ // TODO:  添加您的代码以绘制指定项
int nItem=lpItemStruct->itemID;
if(nItem==-1)
{
return;  
}
else
{
 
//DEFAULT_GUI_FONT
CString strText;
CDC * pDC=CDC::FromHandle(lpItemStruct->hDC); LVITEM item;
item.iItem=nItem;
item.iSubItem=0;
item.mask=LVIF_IMAGE|LVIF_STATE;
item.stateMask=0XFFFF;
GetItem(&item);
BOOL bSelect=item.state&LVIS_SELECTED;
CFont font;
COLORREF bkColor;
COLORREF txtColor ;

if(bSelect)
{ 
    bkColor = m_refselbkColor;
txtColor= m_refselTextColor;
}
else
{ 
bkColor = m_refdefbkColor;
    txtColor = m_refdefTextColor;
}

LV_COLUMN lvc;
lvc.mask=LVCF_FMT|LVCF_WIDTH  ;
for(int nCol=0;this->GetColumn(nCol,&lvc);nCol++)
{  
CRect rcItem;
GetSubItemRect(lpItemStruct->itemID, nCol, LVIR_LABEL, rcItem);  

bool bProcess =false;  
set<int>::const_iterator itr = m_ProcessCol.find(nCol); if(itr != m_ProcessCol.end())
bProcess = true; strText = GetItemText(lpItemStruct->itemID, nCol);   CDC CMDC;
CMDC.CreateCompatibleDC(NULL);
CBitmap * oldbmp = NULL;
CBitmap bmp;
bmp.CreateCompatibleBitmap(pDC,rcItem.Width(),rcItem.Height()); CRect rcCurrentRect;
CRect rcbmp(5,0,rcItem.Width(),rcItem.Height());
oldbmp =CMDC.SelectObject(&bmp);
CMDC.SetBkMode(TRANSPARENT);
CFont * pOldfont= CMDC.SelectObject(&m_font);
BITMAP bm ;
bmp.GetBitmap(&bm);
if (bProcess)
{ 

float with=(float)atof(strText)/100 *rcItem.Width();

CMDC.FillSolidRect(0,0,rcItem.Width(),rcItem.Height(),m_refProcbkColor);
CMDC.FillSolidRect(0,1,with,rcItem.Height(),m_refProcColor);
    
CMDC.SetTextColor(txtColor); if (strText.Trim()!="")
{
strText+="%";
}
else
{
strText="0%";
}

::SetRect(&rcCurrentRect,rcItem.left,rcItem.top,rcItem.left+(int)with,rcItem.bottom);
CMDC.DrawText(strText,&rcbmp,DT_CENTER|DT_SINGLELINE|DT_VCENTER|DT_END_ELLIPSIS); 
pDC->StretchBlt(rcCurrentRect.left,rcCurrentRect.top,rcItem.Width(),rcItem.Height(),
&CMDC,0,0,bm.bmWidth,bm.bmHeight,SRCCOPY); 
}
else
{
CMDC.FillSolidRect(0,0,rcItem.Width(),rcItem.Height(),bkColor);
                CMDC.DrawText(strText,&rcbmp,DT_LEFT|DT_SINGLELINE|DT_VCENTER|DT_END_ELLIPSIS);
pDC->StretchBlt(rcItem.left,rcItem.top,rcItem.Width(),rcItem.Height(),&CMDC,0,0,bm.bmWidth,
bm.bmHeight,SRCCOPY); 
} CMDC.SelectObject(oldbmp);
CMDC.SelectObject(pOldfont);
bmp.DeleteObject();
CMDC.DeleteDC();
}  
}
}