Message Balloons

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Environment: VC++ 6.0, MFC, Windows 2000/XP/9x/ME/NT

Introduction

There are times when one would like to display messages in an non-obtrusive way. Message Balloons are one of the new ways. Message Balloons are taking precedence over message boxes for small display messages as they even prevent the user from clicking an OK and still get the message across. These kind of Message Balloons are becoming a part of standard user interface with MSN explorer and Windows XP. Still no library has been provided for making these balloons. Hence this attempt.

How to use the class provided ?

Include the following two files in your project:

• BalloonTip.h
• BalloonTip.cpp

• CBalloonTip::Show()
• CBalloonTip::Hide()

LOGFONT lf;
::ZeroMemory (&lf, sizeof (lf));
lf.lfHeight = 16;
lf.lfWeight = FW_BOLD;
lf.lfUnderline = FALSE;
::strcpy (lf.lfFaceName, _T("Arial"));

CBalloonTip::Show(
    CPoint(200, 200),  // Point on the screen where 
                       // the tip will be shown
    CSize(250, 100),   // Size of the total rectangle 
                       // encompassing the balloon 
    _T("Please enter a password !!"), // Message to be shown
                                      // in the balloon
    lf,     // LOGFONT structure for 
            // font properties 
    5,      // Time in seconds to show the balloon
    FALSE   // TRUE  == Balloon is up(Balloon Tip is down) 
            // FALSE ==  Balloon is down(Balloon Tip is up)
);

Class Design Details

int CBalloonTip::OnCreate(LPCREATESTRUCT lpCreateStruct) 
{
    //..........Some code
    //...................

    CRgn rgnComb;
    
    rgnComb.CreateRectRgn( t_Rect.left, 
                           t_Rect.top,
                           t_Rect.right,
                           t_Rect.bottom);

    int iRetComb = rgnComb.CombineRgn(&m_rgnTip,
                                      &m_rgnRoundRect,
                                      RGN_OR);
}

BOOL CBalloonTip::PreCreateWindow(CREATESTRUCT& cs)
{
    //...............Some code
    //........................

    if (!::IsWindow(m_wndInvisibleParent.m_hWnd))
    {
        // Try creating the invisible parent window
        PCSTR pstrOwnerClass = ::AfxRegisterWndClass(0);
       
        BOOL bError = m_wndInvisibleParent.CreateEx(
                          0,
                          pstrOwnerClass, 
                          _T(""), 
                          WS_POPUP,
                          0,
                          0,
                          0,
                          0,
                          NULL,
                          0
                      );
    }
}

Window Creation

CBalloonTip* CBalloonTip::Show( CPoint pt,
                                CSize size,
                                CString strMessage,
                                LOGFONT lf,
                                UINT nSecs,
                                BOOL bBalloonUp)
{
    //.........Some code
    //..................

    if (bBalloonUp)
    {
        nRectLeft   = pt.x - (size.cx * 0.65);
        nRectRight  = pt.x + (size.cx * 0.35);
        nRectTop    = pt.y - size.cy;
        nRectBottom = pt.y;
    }
    else
    {
        nRectLeft   = pt.x - (size.cx * 0.35);
        nRectRight  = pt.x + (size.cx * 0.65);
        nRectTop    = pt.y;
        nRectBottom = pt.y + (size.cy);
    }
}

pBalloonTip->Create( CRect( nRectLeft,
                            nRectTop,
                            nRectRight,
                            nRectBottom));

pBalloonTip->MakeVisisble(nSecs);

Overview of the demo project

Compatibility

Conclusion

Downloads