Showing Tool Tips on controls

CToolTipCtrl can be used to attach tool tips for controls. The tool tips can be placed on any controls using AddTool(), a member function of CToolTipCtrl. This article explains how to show Tool Tips for a command button which is placed on a dialog box.

   Tool tips are shown in a round rectangle adjacent to the controls. They are shown when the Mouse cursor is placed on the control.

Tool tips on a dialog - CToolTipCtrl:

• Create a new Dialog based MFC Application. The article assumes the application name as  MFCSample.
• In the MFCSampleDlg.h file, add a member variable for CToolTipCtrl inside CMFCSampleDlg class as follows.

CToolTipCtrl *m_ToolTip;

• Add a Command Button to the dialog box. Create a member variable for the button as m_TESTBUTTON.
• In the OnInitDialog function of the CMFCSampleDlg class ( MFCSampleDlg.cpp) add the following code.

---

m_ToolTip= new CToolTipCtrl();
EnableToolTips(TRUE); ////// missed line in the original paper. Without this line the code snippet does not work.
m_ToolTip->Create(this);

m_ToolTip->AddTool(&m_TESTBUTTON,"Test Button");

m_ToolTip->Activate(TRUE);

---

• The above code adds a tool tip for the command button. If the mouse cursor is placed on the button, it shows a tool tip as "Test Button".
• More controls can be added with the tool tip as above.
• The following version of PreTranslateMessage should be placed in MFCSampleDlg.cpp, to override the default one.

---

BOOL CMFCSampleDlg::PreTranslateMessage(MSG* pMsg)
{
    // TODO: Add your specialized code here and/or call the base class

    if(m_ToolTip != NULL)
       m_ToolTip->RelayEvent(pMsg);

    return CDialog::PreTranslateMessage(pMsg);
}

---

   The above pretranslatemessage version, ensures that Windows gets the notifications required for the Tool tips.

   The above program creates the CToolTipCtrl variable using the new operator. So the memory should be freed at the end of the program by using the delete operator.