How to add tooltips for controls to an MFC modal dialog box

MORE INFORMATION

Step-by-step examples

1. Use the Appwizard in Visual C++ to generate an MFC application. Name the application Tooltips. Use all the Appwizard default settings.
2. Use ClassWizard to add a PreTranslateMessage override to CAboutDialog.

      CAboutDialog::PreTranslateMessage(MSG* pMsg)
      {
           if (NULL != m_pToolTip)
               m_pToolTip->RelayEvent(pMsg);
   
           return CDialog::PreTranslateMessage(pMsg);
      }

3. Use ClassWizard to add a member variable for the OK button in the CAboutDlg class. Name the member variable m_btOK. Also, add an m_pToolTip pointer to a CToolTipCtrl object.

      class CAboutDlg : public CDialog
      {
      public:
          CAboutDlg();
   
          // Dialog Data
          //{{AFX_DATA(CAboutDlg)
          enum { IDD = IDD_ABOUTBOX };
          CButton   m_btOK;
          //}}AFX_DATA
   
          CToolTipCtrl* m_pToolTip;
   
          //...
      };

4. Add code to the CAboutDlg class constructor and destructor to initialize and release the tooltip object. You may first have to add a default destructor.

      CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
      {
          m_pToolTip = NULL;
      }
   
      CAboutDlg::~CAboutDlg()
      {
          delete m_pToolTip;
      }

5. Override the OnInitDialog function of the CAboutDlg class to set up the tooltip control.

      BOOL CAboutDlg::OnInitDialog()
      {
         CDialog::OnInitDialog();
   
          //Set up the tooltip
          m_pToolTip = new CToolTipCtrl;
          if(!m_pToolTip->Create(this))
          {
              TRACE("Unable To create ToolTip\n");
              return TRUE;
          }
   
          if(m_pToolTip->AddTool(this, "About Box"))
          {
              TRACE("Unable to add Dialog to the tooltip\n");
          }
   
          if (m_pToolTip->AddTool(&m_btOK,"OK Button"))
          {
              TRACE("Unable to add OK button to the tooltip\n");
          }
   
          m_pToolTip->Activate(TRUE);
   
          return TRUE;
      }

6. Rebuild the application. Then, open the About dialog box. You will see the tooltips.

1. Use the Appwizard in Visual C++ to generate an MFC application. Name the application Tooltips. Use all the Appwizard default settings.
2. Include the <Afxcmn.h> header file in the Stdafx.h file.
3. Add the following member variables to the CTooltipsApp class in the Tooltips.h file.

      class CTooltipsApp : public CWinApp
      {
          //...
      public:
          HWND    m_hwndDialog;
          CToolTipCtrl*   m_gpToolTip;
   
          //...
      };

4. Initialize the two variables in the application's constructor to NULL.

      CTooltipsApp::CTooltipsApp()
      {
          m_hwndDialog = NULL;
          m_gpToolTip = NULL;
      }

5. Override the CTooltipsApp::ProcessMessageFilter function.

      BOOL CTooltipsApp::ProcessMessageFilter(int code, LPMSG lpMsg)
      {
          if (m_hwndDialog != NULL)
              if (lpMsg->hwnd == m_hwndDialog ||
                  ::IsChild(m_hwndDialog, lpMsg->hwnd))
              {
                  if (NULL != m_gpToolTip)
                      m_gpToolTip->RelayEvent(lpMsg);
              }
              return CWinApp::ProcessMessageFilter(code, lpMsg);
      }

6. Use ClassWizard to add a member variable for the OK button in the CAboutDlg class. Name the member variable m_btOK. Also, add an m_pToolTip pointer to a CToolTipCtrl object.

      class CAboutDlg : public CDialog
      {
      public:
          CAboutDlg();
   
          // Dialog Data
          //{{AFX_DATA(CAboutDlg)
          enum { IDD = IDD_ABOUTBOX };
          CButton   m_btOK;
          //}}AFX_DATA
   
          CToolTipCtrl* m_pToolTip;
   
          //...
      };

7. Add code to the CAboutDlg class constructor and destructor to initialize and release the tooltip object. You may first have to add a default destructor.

      CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
      {
          m_pToolTip = NULL;
      }
   
      CAboutDlg::~CAboutDlg()
      {
          delete m_pToolTip;
      }

8. Override the OnInitDialog function of the CAboutDlg class to pass the handle of the dialog box to the application.

      BOOL CAboutDlg::OnInitDialog()
      {
          CDialog::OnInitDialog();
   
          ((CTooltipsApp*)AfxGetApp())->m_hwndDialog=m_hWnd;
   
          if (!m_pToolTip)
          {
              m_pToolTip = new CToolTipCtrl;
              if(!m_pToolTip->Create(this))
             {
                  TRACE("Unable To create ToolTip\n");
                  return TRUE;
            }
   
              ((CTooltipsApp*)AfxGetApp())->m_gpToolTip = m_pToolTip;
   
              if(m_pToolTip->AddTool(this, "About Box"))
              {
                  TRACE("Unable to add Dialog to the tooltip\n");
              }
   
              if (m_pToolTip->AddTool(&m_btOK,"OK Button"))
              {
                  TRACE("Unable to add OK button to the tooltip\n");
              }
   
              m_pToolTip->Activate(TRUE);
          }
   
         return TRUE;//return TRUE unless you set the focus to a control
                     //EXCEPTION: OCX Property Pages should return FALSE
       }

9. Override the PostNcDestroy function of the CAboutDlg class to reset the variables in the application class.

      void CAboutDlg::PostNcDestroy( )
      {
          CDialog::PostNcDestroy();
   
          ((CToolTipsApp*)AfxGetApp())->m_hwndDialog= NULL;
          ((CToolTipsApp*)AfxGetApp())->m_gpToolTip= NULL;
      }

10. Rebuild the application. Then, open the About dialog box. You will see the tooltips.