void CButtonEx::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
CDC *pDC=CDC::FromHandle(lpDrawItemStruct->hDC);
CRect m_rect;
m_rect=lpDrawItemStruct->rcItem;
CMemDC m_pDC(pDC);
pDC->SelectObject(&font);
CString text;
GetWindowText(text);
m_pDC.SelectObject(&font);
switch(m_Status)
{
case NORMAL:
{
CBitmap bitmap;
bitmap.LoadBitmap(IDB_BUTTON_NORMAL);
CDC memdc;
memdc.CreateCompatibleDC(NULL);
memdc.SelectObject(&bitmap);
m_pDC.BitBlt(0,0,m_rect.Width(),m_rect.Width(),&memdc,0,0,SRCCOPY);
m_pDC.SetBkMode(TRANSPARENT);
m_pDC.DrawText(text,&m_rect,DT_VCENTER|DT_SINGLELINE|DT_CENTER);
memdc.DeleteDC();
}
break;
case HOVER:
{
CBitmap bitmap;
bitmap.LoadBitmap(IDB_BUTTON_HOVER);
CDC memdc;
memdc.CreateCompatibleDC(NULL);
memdc.SelectObject(&bitmap);
m_pDC.BitBlt(0,0,m_rect.Width(),m_rect.Width(),&memdc,0,0,SRCCOPY);
m_pDC.SetBkMode(TRANSPARENT);
m_pDC.DrawText(text,&m_rect,DT_VCENTER|DT_SINGLELINE|DT_CENTER );
memdc.DeleteDC();
}
break;
case DOWN:
{
CBitmap bitmap;
bitmap.LoadBitmap(IDB_BUTTON_DOWN);
CDC memdc;
memdc.CreateCompatibleDC(NULL);
memdc.SelectObject(&bitmap);
m_pDC.BitBlt(0,0,m_rect.Width(),m_rect.Width(),&memdc,0,0,SRCCOPY);
m_pDC.SetBkMode(TRANSPARENT);
m_pDC.DrawText(text,&m_rect,DT_VCENTER|DT_SINGLELINE|DT_CENTER );
memdc.DeleteDC();
}
break;
default:
{
}
break;
}
}
CDC::FromHandle 得到的是一个临时变量的CDC 指针， 要不要释放资源呢？
