自绘列表框控件显示略缩图----再稍微改进点点。。

每天思考一点无聊的问题，又是接上一篇日记的列表框自绘，在上一个自绘里面图片是用WINDOWS自己画上去的，这次彻底的全部的自己绘制（包括文字），这样做的好处是图片上不会覆盖一层阴影影响美观，改动是下面的红色显示的代码片段，有一个问题不知道为什么，就是下面这句

GetSubItemRect(nItem, nSubItem, LVIR_ICON, rect);

得到的矩形rect的宽度总是比图片宽度大42像素(列表框在ICO模式时)，why？

只是在前面的基础上修改这两个函数。。。

///
  
   
OnNMCustomdraw
  
void CListImageCtrl::OnNMCustomdraw(NMHDR *pNMHDR, LRESULT *pResult)
  
{
  
//LPNMCUSTOMDRAW pNMCD = reinterpret_cast<LPNMCUSTOMDRAW>(pNMHDR);
  
NMLVCUSTOMDRAW* pLVCD = reinterpret_cast<NMLVCUSTOMDRAW*>(pNMHDR);
  

  
//TRACE("CListImageCtrl::OnNMCustomdraw()");
  
// Take the default processing unless we set this to something else below.
  
*pResult = CDRF_DODEFAULT;
  

  
// First thing - check the draw stage. If it's the control's prepaint
  
// stage, then tell Windows we want messages for every item.
  

  
if (pLVCD->nmcd.dwDrawStage == CDDS_PREPAINT)
  
{
  
*pResult = CDRF_NOTIFYITEMDRAW;
  
}
  
else if (pLVCD->nmcd.dwDrawStage == CDDS_ITEMPREPAINT)
  
{
  
// This is the notification message for an item.  We'll request
  
// notifications before each subitem's prepaint stage.
  
int nItem = static_cast<int> (pLVCD->nmcd.dwItemSpec);
  
int nSubItem = pLVCD->iSubItem;
  
CDC* pDC = CDC::FromHandle(pLVCD->nmcd.hdc);
  
CRect rect;
  
GetSubItemRect(nItem, nSubItem, LVIR_ICON, rect);
  

  
XLISTCTRLDATA *pXLCD = (XLISTCTRLDATA *) pLVCD->nmcd.lItemlParam;
  
ASSERT(pXLCD);
  

  
COLORREF crText  = m_crWindowText;
  
COLORREF crBkgnd = m_crWindow;
  

  
if (pXLCD)
  
{
  
crText  = pXLCD[nSubItem].crText;
  
crBkgnd = pXLCD[nSubItem].crBackground;
  

  
if (!pXLCD[0].bEnabled)
  
crText = m_crGrayText;
  
}
  

  
// store the colors back in the NMLVCUSTOMDRAW struct
  
pLVCD->clrText = crText;
  
pLVCD->clrTextBk = crBkgnd;
  

  

  
//draw image,
  
rect.left += 19;
  
rect.right -= 19;
  
DrawImage(nItem, nSubItem, pDC, crText, crBkgnd, rect, pXLCD);
  

  
//draw checkbox
  
if (pXLCD && (pXLCD[nSubItem].nCheckedState != -1))
  
DrawCheckbox(nItem, nSubItem, pDC, crText, crBkgnd, rect,pXLCD);
    
//draw text
  
GetSubItemRect(nItem, nSubItem, LVIR_LABEL, rect);
  

  
DrawText(nItem, nSubItem, pDC, crText, crBkgnd, rect, pXLCD);
  

  
*pResult = CDRF_SKIPDEFAULT;   //we have done all the paint
  

  
}
  
else if (pLVCD->nmcd.dwDrawStage == (CDDS_ITEMPREPAINT | CDDS_SUBITEM))
  
{
  

  
*pResult = CDRF_DODEFAULT;
  
}
  

  
}
  

  
  

   ///
  
   

   // DrawImage
  
   

   int CListImageCtrl::DrawImage(int nItem,
  
   

   

   

   

   

   

   

   {
  
   
if (rect.IsRectEmpty())  
   
{  
   
return 0;  
   
}  
   

   
   
GetDrawColors(nItem, nSubItem, crText, crBkgnd);  
   

   
   

   CBrush bkBrush(crBkgnd);
   
CRgn rgn;
   
rgn.CreateRectRgn(rect.left,rect.top,rect.right,rect.bottom);
   
pDC->FrameRgn(&rgn,&bkBrush,2,2);     //draw my border
   

   
int nGap = 0;
   
rect.left += 0;  
   

   
   
CImageList* pImageList = GetImageList(LVSIL_SMALL);  
   
if (pImageList)  
   
{  
   
SIZE sizeImage;  
   
sizeImage.cx = sizeImage.cy = 0;  
   
IMAGEINFO info;  
   

   
   
int nImage = -1;  
   
if (pXLCD)  
   
nImage = pXLCD[nSubItem].nImage;  
   

   
   
if (nImage == -1)  
   
return 0;  
   

   
   
if (pImageList->GetImageInfo(nImage, &info))  
   
{  
   
sizeImage.cx = info.rcImage.right - info.rcImage.left;  
   
sizeImage.cy = info.rcImage.bottom - info.rcImage.top;  
   
}  
   

   
   
if (nImage >= 0)  
   
{  
   
if (rect.Width() > 0)  
   
{  
   
POINT point;  
   

   
   
point.y = rect.CenterPoint().y - (sizeImage.cy >> 1);  
   
point.x = rect.CenterPoint().x - (sizeImage.cx >> 1);  
   

   
   
SIZE size;  
   
size.cx = rect.Width() < sizeImage.cx ? rect.Width() : sizeImage.cx;  
   
size.cy = rect.Height() < sizeImage.cy ? rect.Height() : sizeImage.cy;  
   

   
   
// save image list background color  
   
COLORREF rgb = pImageList->GetBkColor();  
   

   
   
// set image list background color  
   
pImageList->SetBkColor(crBkgnd);  
   
pImageList->DrawIndirect(pDC, nImage, point, size, CPoint(0, 0));  
   
pImageList->SetBkColor(rgb);  
   

   
   
nGap = sizeImage.cx + 5;    
   
}  
   
}  
   
}  
   

   
   
return nGap;  
   

   }