balloontip.cpp

一个邮件监控程序

  if (CFrameWnd::OnCreate(lpCreateStruct) == -1)
  {
    return -1;
  }
  
  // Remove caption and thick frame for proper shading
  ModifyStyle(WS_CAPTION | WS_THICKFRAME, 0); 
  
  CRect t_Rect;
  GetClientRect(&t_Rect);  // Get the client rectangle to set the balloon region
  
  if (m_bBalloonUp)
  {
    // Calculation of Text window, where to write text in the balloon
    m_rectText.left   = t_Rect.Width() * 0.10; 
    m_rectText.right  = t_Rect.Width() * 0.90;
    m_rectText.top    = t_Rect.Height() * 0.10; 
    m_rectText.bottom = t_Rect.Height()* 0.70; 
    
    // Create an elliptical region out of the client rectangle
    m_rgnRoundRect.CreateRoundRectRgn(
      t_Rect.left, 
      t_Rect.top, 
      t_Rect.right,
      t_Rect.bottom -(t_Rect.Height() * 0.25), 
      abs(t_Rect.left - t_Rect.right) * 0.18,
      t_Rect.Height() * 0.25
      );
    
    // Start the process of creating the balloon tip
    CPoint ptTri[4];
    ptTri[0].x =(t_Rect.left) +(t_Rect.Width() * 0.93);
    ptTri[0].y =(t_Rect.bottom) -(t_Rect.Height() * 0.40);
    
    ptTri[1].x =(t_Rect.left) +(t_Rect.Width() * 0.65);
    ptTri[1].y = t_Rect.bottom;
    
    ptTri[2].x =(t_Rect.left) +(t_Rect.Width() * 0.70);
    ptTri[2].y =(t_Rect.bottom) -(t_Rect.Height() * 0.40);
    
    ptTri[3].x =(t_Rect.left) +(t_Rect.Width() * 0.93);
    ptTri[3].y =(t_Rect.bottom) -(t_Rect.Height() * 0.40);
    
    m_rgnTip.CreatePolygonRgn(ptTri, 3, ALTERNATE);
  }
  else
  {
    // Calculation of Text window, where to write text in the balloon
    m_rectText.left   = t_Rect.Width() * 0.10;
    m_rectText.right  = t_Rect.Width() * 0.90;
    m_rectText.top    = t_Rect.Height() * 0.30;
    m_rectText.bottom = t_Rect.Height() * 0.90;
    
    // Create an elliptical region out of the client rectangle
    m_rgnRoundRect.CreateRoundRectRgn(
      t_Rect.left,
      t_Rect.bottom -(t_Rect.Height() * 0.75), 
      t_Rect.right, 
      t_Rect.bottom, 
      abs(t_Rect.left - t_Rect.right) * 0.18,
      t_Rect.Height() * 0.25
      );
    
    // Start the process of creating the balloon tip
    CPoint ptTri[4];
    ptTri[0].x =(t_Rect.left) +(t_Rect.Width() * 0.07);
    ptTri[0].y =(t_Rect.Height() * 0.40);
    
    ptTri[1].x =(t_Rect.left) +(t_Rect.Width() * 0.35);
    ptTri[1].y = t_Rect.bottom - t_Rect.Height();
    
    ptTri[2].x =(t_Rect.left) +(t_Rect.Width() * 0.30);
    ptTri[2].y = t_Rect.Height() * 0.40;
    
    ptTri[3].x =(t_Rect.left) +(t_Rect.Width() * 0.07);
    ptTri[3].y = t_Rect.Height() * 0.40;
    
    m_rgnTip.CreatePolygonRgn(ptTri, 3, ALTERNATE);
  }
  
  // Create the combined region with ellipse and tip
  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);
  
  if (iRetComb == ERROR)
  {
    ::AfxMessageBox("ERROR in Combining Region");
    return -1;
  }
  
  SetWindowRgn(rgnComb.operator HRGN(), TRUE);
  
  return 0;
}




/*-----------------------------------------------------------------------------
 Function : CBalloonTip::OnPaint()

 Created: Nov 1, 2001

 Abstract : Gets called by MFC for a WM_PAINT message

 Parameters : 
        See MFC documentation

 Return Value : void

 Exceptions : none

 Revisions : none
----------------------------------------------------------------------------*/

void CBalloonTip::OnPaint() 
{
  CPaintDC dc(this); // device context for painting
  
  CRect t_Rect;
  GetClientRect(&t_Rect);
  
  // Get the total balloon, inclding all cut out regions
  CRgn rgnComb;	
  rgnComb.CreateRectRgn(t_Rect.left, t_Rect.top, t_Rect.right, t_Rect.bottom);
  
  // Create a balloon tip from this total region
  int iRetComb = rgnComb.CombineRgn(&m_rgnTip, &m_rgnRoundRect, RGN_OR);
  if (iRetComb == ERROR)
  {
    ::AfxMessageBox("ERROR in Combining Region");
    return;
  }
  
  CBrush brOutlineBrush;
  brOutlineBrush.CreateSolidBrush(RGB(0, 0, 0)); // blue
  
  CBrush brFillBrush;
  brFillBrush.CreateSolidBrush(RGB(249, 254, 188)); // light yellow
  
  
  dc.FillRgn(&rgnComb, &brFillBrush);  // Fill the balloon
  dc.FrameRgn(&rgnComb, &brOutlineBrush, 2, 1); // Outline the balloon
  
  int nBkMode          = dc.SetBkMode(TRANSPARENT);
  COLORREF clrPrevious =  dc.SetTextColor(RGB(255, 0, 0));
  CFont *pFont = dc.SelectObject(&m_fontBalloonText);
  
  CSize czTextWidth = dc.GetTextExtent(m_strMessage);
  
  if (czTextWidth.cx < m_rectText.Width())
  {
    dc.DrawText(m_strMessage, m_rectText, DT_CENTER | DT_VCENTER | DT_SINGLELINE);
  }
  
  else
  {
    dc.DrawText(m_strMessage, m_rectText, DT_CENTER | DT_WORDBREAK);
  }
  
  // Restore the DC to its oroginal state
  dc.SelectObject(pFont);
  dc.SetBkColor(nBkMode);
  dc.SetTextColor(clrPrevious);
}




/*-----------------------------------------------------------------------------
 Function : CBalloonTip::PreCreateWindow(CREATESTRUCT& cs)

 Created: Dec 07, 2001

 Abstract : Called by MFC when a before WM_CREATE message is received by the
            window.

            We override this function so that the window so created is not
            visible in the Taskbar. We make this window the child of an
            invisible parent m_wndInvisibleParent.

 Parameters : Look in MFC documentation

 Return Value : BOOL

 Exceptions : none

 Revisions : none
----------------------------------------------------------------------------*/

BOOL CBalloonTip::PreCreateWindow(CREATESTRUCT& cs)
{
  if (!CWnd::PreCreateWindow(cs))
  {
    return FALSE;
  }
  
 	// Create invisible parent window
 	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
      );
    
    if (bError == FALSE)
    {
      return FALSE;
    }
 	}
  
  // Set the invisible window as the parent of "this" window
  cs.hwndParent = m_wndInvisibleParent.m_hWnd;
  
  return TRUE;
}




/*-----------------------------------------------------------------------------
 Function : CBalloonTip::Create()

 Created: Dec 07, 2001

 Abstract : Called by the static CBalloonTip to create a Windows(R) window 

 Parameters : rect-> a rectangle in screen co ordinates where the balloon
              will be displayed.

 Return Value : BOOL

 Exceptions : none

 Revisions : none
----------------------------------------------------------------------------*/

BOOL CBalloonTip::Create(CRect rect)
{
  m_rectWindow = rect;
  
  PCSTR pstrOwnerClass = ::AfxRegisterWndClass(0);
  BOOL bResult = CFrameWnd::Create(pstrOwnerClass, NULL, WS_OVERLAPPED, m_rectWindow);
  
  return bResult;
}





/*-----------------------------------------------------------------------------
 Function : CBalloonTip::Hide()

 Created: Dec 08, 2001

 Abstract : Provided to destroy a balloon before it self destructs. If it is 
            already hidden, it will have no effect.
            
 Parameters : CBalloonTip*

 Return Value : void

 Exceptions : none

 Revisions : none
----------------------------------------------------------------------------*/

void CBalloonTip::Hide(CBalloonTip* pBalloonTip)
{
  if (CBalloonTip::nBalloonInstances != 0)
  {
    pBalloonTip->ShowWindow(SW_HIDE);
    pBalloonTip->KillTimer(ID_TIMER);
    pBalloonTip->DestroyWindow();
  }
}




/*-----------------------------------------------------------------------------
  int CBalloonTip::nBalloonInstances;

  Abstract: Used for preventing more than one instance of the class CBalloonTip
-----------------------------------------------------------------------------*/

int CBalloonTip::nBalloonInstances = 0;




/*-----------------------------------------------------------------------------
 Function : CBalloonTip::PostNcDestroy()

 Created: Dec 08, 2001

 Abstract : Last function the window receives when it is destroyed.
            Used for resetting the counter CBalloonTip::nBalloonInstances to 0,
            so that a new instance of this class can be created.
            
 Parameters : void

 Return Value : void

 Exceptions : none

 Revisions : none
----------------------------------------------------------------------------*/

void CBalloonTip::PostNcDestroy()
{
  CBalloonTip::nBalloonInstances = 0;
  CFrameWnd::PostNcDestroy();
}