Unknown bug

I use MFC to build the interface of a program and I write a new function to re-draw the window style and dialog style (similar to XP style). It's all ok when I run the program at the initial window size, but if I let the window to be max size, the menu bar becomes something wrong, I must double click each menu item, the single click is unavailable.

Code:

void CClassname::DrawTitleBar(CDC *pDC) { if (m_hWnd) { CBrush Brush(RGB(0,100,255)); CBrush* pOldBrush = pDC->SelectObject(&Brush); CRect rtWnd, rtTitle, rtButtons; GetWindowRect(&rtWnd); //Get the position of title rtTitle.left = GetSystemMetrics(SM_CXFRAME); rtTitle.top = GetSystemMetrics(SM_CYFRAME); rtTitle.right = rtWnd.right - rtWnd.left - GetSystemMetrics(SM_CXFRAME); rtTitle.bottom = rtTitle.top + GetSystemMetrics(SM_CYSIZE); CPoint point; //draw the top of the frame point.x = rtWnd.Width(); point.y = GetSystemMetrics(SM_CYSIZE) + GetSystemMetrics(SM_CYFRAME)+20; pDC->PatBlt(0, 0, point.x, point.y, PATCOPY); //draw the left of the frame point.x = GetSystemMetrics(SM_CXFRAME) + 1; point.y = rtWnd.Height(); pDC->PatBlt(0, 0, point.x, point.y, PATCOPY); //draw the bottom of the frame point.x = rtWnd.Width(); point.y = GetSystemMetrics(SM_CYFRAME) + 1; pDC->PatBlt(0, rtWnd.Height()-point.y, point.x, point.y, PATCOPY); //draw the right of the frame point.x = GetSystemMetrics(SM_CXFRAME) + 1; point.y = rtWnd.Height(); pDC->PatBlt(rtWnd.Width()-point.x, 0, point.x, point.y, PATCOPY); //Re-draw icon m_rtIcon.left = rtWnd.Width() - 135; m_rtIcon.top = GetSystemMetrics(SM_CYFRAME); m_rtIcon.right = m_rtIcon.left + 32; m_rtIcon.bottom = m_rtIcon.top + 32; ::DrawIconEx(pDC->m_hDC, m_rtIcon.left, m_rtIcon.top, m_hIcon, m_rtIcon.Width(), m_rtIcon.Height(), 0, NULL, DI_NORMAL); m_rtIcon.OffsetRect(rtWnd.TopLeft()); //Prepare for the XP sytle button CBitmap* pBitmap = new CBitmap; CBitmap* pOldBitmap; CDC* pDisplayMemDC=new CDC; pDisplayMemDC->CreateCompatibleDC(pDC); //Re-draw close button rtButtons.left = rtTitle.right - 19; rtButtons.top = rtTitle.top; rtButtons.right = rtButtons.left + 19; rtButtons.bottom = rtButtons.top + 19; pBitmap->LoadBitmap(IDB_EXIT_NORMAL); pOldBitmap=(CBitmap*)pDisplayMemDC->SelectObject(pBitmap); pDC->BitBlt(rtButtons.left, rtButtons.top, rtButtons.Width(), rtButtons.Height(), pDisplayMemDC, 0, 0, SRCCOPY); pDisplayMemDC->SelectObject(pOldBitmap); m_rtButtExit = rtButtons; m_rtButtExit.OffsetRect(rtWnd.TopLeft()); pBitmap->DeleteObject(); //Re-draw restore button rtButtons.right = rtButtons.left - 3; rtButtons.left = rtButtons.right - 19; if (IsZoomed()) pBitmap->LoadBitmap(IDB_RESTORE_NORMAL); else pBitmap->LoadBitmap(IDB_MAX_NORMAL); pOldBitmap=(CBitmap*)pDisplayMemDC->SelectObject(pBitmap); pDC->BitBlt(rtButtons.left, rtButtons.top, rtButtons.Width(), rtButtons.Height(), pDisplayMemDC, 0, 0, SRCCOPY); pDisplayMemDC->SelectObject(pOldBitmap); m_rtButtMax = rtButtons; m_rtButtMax.OffsetRect(rtWnd.TopLeft()); pBitmap->DeleteObject(); //Re-draw minisize button rtButtons.right = rtButtons.left - 3; rtButtons.left = rtButtons.right - 19; pBitmap->LoadBitmap(IDB_MIN_NORMAL); pOldBitmap=(CBitmap*)pDisplayMemDC->SelectObject(pBitmap); pDC->BitBlt(rtButtons.left, rtButtons.top, rtButtons.Width(), rtButtons.Height(), pDisplayMemDC, 0, 0, SRCCOPY); pDisplayMemDC->SelectObject(pOldBitmap); m_rtButtMin = rtButtons; m_rtButtMin.OffsetRect(rtWnd.TopLeft()); pBitmap->DeleteObject(); //Re-draw caption int nOldMode = pDC->SetBkMode(TRANSPARENT); COLORREF clOldText=pDC->SetTextColor(RGB(255, 255, 255)); pDC->SelectStockObject(SYSTEM_FIXED_FONT); rtTitle.left += 2; rtTitle.top += GetSystemMetrics(SM_CYSIZE); rtTitle.bottom = rtTitle.top + 30; CString m_strTitle; GetWindowText(m_strTitle); pDC->DrawText(m_strTitle, &rtTitle, DT_LEFT); pDC->SetBkMode(nOldMode); pDC->SetTextColor(clOldText); ReleaseDC(pDisplayMemDC); delete pDisplayMemDC; delete pBitmap; } }

And you must add a DefWindowProc function and override it

Code:

LRESULT CClassname::DefWindowProc(UINT message, WPARAM wParam, LPARAM lParam) { LRESULT lrst=CDialog::DefWindowProc(message, wParam, lParam); if (!::IsWindow(m_hWnd)) return lrst; if (message == WM_MOVE||message == WM_PAINT||message==WM_NCPAINT||message==WM_NCACTIVATE ||message == WM_NOTIFY) { CDC* pWinDC = GetWindowDC(); if (pWinDC) DrawTitleBar(pWinDC); ReleaseDC(pWinDC); } return lrst; }