Adding a Full Screen Feature to an MFC Application

Link : http://support.microsoft.com/kb/q164162/

SUMMARY
The FSCRN sample includes code that you can use to add a Full Screen feature to a Visual C++ 4.x MFC Application. This is similar to what you see when you select the Full Screen menu item in Microsoft Developer Studio. The code shows which functions must be created and demonstrates how you can create a floating toolbar, which you can click to undo the Full Screen mode.

The following files are available for download from the Microsoft Download Center:

http://download.microsoft.com/download/vc40pro/sample5/1/nt4/en-us/fscrn.exe

MORE INFORMATION
The sample code below has been added to the CMainFrame class of the AppWizard-generated application. Here is a list of the four functions and what they accomplish:

1. OnViewFullScreen - Handler for the Full Screen menu item.
2. OnGetMinMaxInfo - Traps the WM_GETMINMAXINFO message to allow you to increase the size of the window.
3. IsFullScreen- Tests whether the application is in full screen mode.
4. OnUpdateViewFullScreen - Checks or unchecks the Full Screen menu item depending on the mode the application is in.


[code]Sample code[/code]


void CMainFrame::OnViewFullScreen()
{
    RECT rectDesktop;
    WINDOWPLACEMENT wpNew;

    if (!IsFullScreen())
    {
        // need to hide all status bars
        m_wndStatusBar.ShowWindow(SW_HIDE);
        m_wndToolBar.ShowWindow(SW_HIDE);

        // We'll need these to restore the original state.
        GetWindowPlacement (&m_wpPrev);

        m_wpPrev.length = sizeof m_wpPrev;

        //Adjust RECT to new size of window
        ::GetWindowRect ( ::GetDesktopWindow(), &rectDesktop );
        ::AdjustWindowRectEx(&rectDesktop, GetStyle(), TRUE,
        GetExStyle());

        // Remember this for OnGetMinMaxInfo()
        m_FullScreenWindowRect = rectDesktop;

        wpNew = m_wpPrev;
        wpNew.showCmd = SW_SHOWNORMAL;
        wpNew.rcNormalPosition = rectDesktop;

        m_pwndFullScrnBar=new CToolBar;

        if(!m_pwndFullScrnBar->Create(this, CBRS_SIZE_DYNAMIC|CBRS_FLOATING) || !m_pwndFullScrnBar->LoadToolBar(IDR_FULLSCREEN))
        {
            TRACE0("Failed to create toolbar\n");
            return;     // fail to create
        }

        //don't allow the toolbar to dock
        m_pwndFullScrnBar->EnableDocking(0);
        m_pwndFullScrnBar->SetWindowPos(0,100,100,0,0,SWP_NOSIZE|SWP_NOZORDER|SWP_NOACTIVATE|SWP_SHOWWINDOW);
        m_pwndFullScrnBar->SetWindowText(_T("Full Screen"));
        FloatControlBar(m_pwndFullScrnBar, CPoint(100,100));
        m_bFullScreen=TRUE;
    }
    else
    {
        m_pwndFullScrnBar->DestroyWindow();
        delete m_pwndFullScrnBar;

        m_bFullScreen=FALSE;

        m_wndStatusBar.ShowWindow(SW_SHOWNORMAL);
        m_wndToolBar.ShowWindow(SW_SHOWNORMAL);
        wpNew = m_wpPrev;
    }

    SetWindowPlacement ( &wpNew );
}

void CMainFrame::OnGetMinMaxInfo(MINMAXINFO FAR* lpMMI)
{
    if (IsFullScreen())
    {
        lpMMI->ptMaxSize.y = m_FullScreenWindowRect.Height();
        lpMMI->ptMaxTrackSize.y = lpMMI->ptMaxSize.y;
        lpMMI->ptMaxSize.x = m_FullScreenWindowRect.Width();
        lpMMI->ptMaxTrackSize.x = lpMMI->ptMaxSize.x;
    }
}

BOOL CMainFrame::IsFullScreen()
{
    return m_bFullScreen;
}

void CMainFrame::OnUpdateViewFullScreen(CCmdUI* pCmdUI)
{
    pCmdUI->Enable();

    if (IsFullScreen())
    pCmdUI->SetCheck();
    else
    pCmdUI->SetCheck(0);
}