Sample: WrapTBar.exe Wraps Toolbar During CFrameWnd Resizing

MORE INFORMATION

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WrapTBar.exe

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   File Name                Size
   ---------------------------------------------------------

   WrapFixedToolBar.h,      Implement the CToolBar-derived class
   WrapFixedToolBar.cpp     that would provide the desired behavior.
   WrapToolBar.h            The main header file (CWrapToolBarApp class).
   WrapToolBar.cpp          The main application source file.
   WrapToolBar.rc           Listing of all Windows resources used.
   res\WrapToolBar.ico      Icon file.
   res\WrapToolBar.rc2      Resources not edited by the IDE.
   WrapToolBar.clw          Information used by ClassWizard.
   MainFrm.h,
   MainFrm.cpp              The frame class CMainFrame.
   res\Toolbar.bmp          Used to create tiled images for the toolbar.
   WrapToolBarDoc.h,
   WrapToolBarDoc.cpp       The document CWrapToolBarDoc.
   WrapToolBarView.h,
   WrapToolBarView.cpp      The view of the document.
   StdAfx.h,
   StdAfx.cpp               Used to build a precompiled header (PCH) file.
   Resource.h               Defines new resource IDs.
				

The core of this solution relies on handling the MFC private WM_SIZEPARENT message. This message is sent to all child-windows of CFrameWnd-derived classes when the frame window is resized, ensuring the proper negotiation of the client space.

By deriving a new class from CToolBar and providing a handler for WM_SIZEPARENT, we solve the problem. The handler resembles the following:

LRESULT CWrapFixedToolBar::OnSizeParent(WPARAM, LPARAM lParam)
{
    AFX_SIZEPARENTPARAMS* lpLayout = (AFX_SIZEPARENTPARAMS*)lParam;
    DWORD dwStyle = RecalcDelayShow(lpLayout);

    if ((dwStyle & WS_VISIBLE) && (dwStyle & CBRS_ALIGN_ANY) != 0)
    {
        CRect rect;
        rect.CopyRect(&lpLayout->rect);
        // Reposition buttons on toolbar according to available space.
        SetWidth(rect.Width());
        // Pass message processing to base class handler.
        CToolBar::OnSizeParent(0, lParam);
    }
    return 0;
}
				

The CWrapFixedToolBar::SetWidth() function should be implemented as:

void CWrapFixedToolBar::SetWidth(long lWidth)
{
    TBBUTTON* pData;
    // Read the toolbar buttons.
    int nCount = GetToolBarCtrl().GetButtonCount();
    if (nCount != 0)
    {
        pData = new TBBUTTON[nCount];
        for (int i = 0; i < nCount; i++)
            _GetButton(i, &pData[i]);
    }
    else
        return;

    // Get the toolbar buttons offsets in the toolbar area.
    CRect rect;
    rect.SetRectEmpty();
    CalcInsideRect(rect, TRUE);

    // Wrap buttons according to available space.
    WrapToolBar(pData, nCount, lWidth - abs(rect.Width()));

    // Save toolbar buttons to underlying toolbar control.
    if (nCount != 0)
        for (int i = 0; i < nCount; i++)
            _SetButton(i, &pData[i]);

    if (pData)
        delete [] pData;
}
				

Finally, change the toolbar creation code in CMainFrame::OnCreate() to make it CBRS_SIZE_FIXED and to disable the docking capabilities.