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How to Add Tooltips for Controls to an MFC Property Page


Roger Onslow -- Roger_Onslow@compsys.com.au
Thursday, June 06, 1996


Environment: VC++ 4.0 / Win 95

How to Add Tooltips for Controls to an MFC Property Page

PSS ID Number: 

Article last modified on 5-Jun-1996

4.00 4.10

-----------------------------------------------------------------------------
The information in this article applies to:
 - The Microsoft Foundation Classes (MFC) included with:
   Microsoft Visual C++, 32-bit Edition, versions 4.0 and later
-----------------------------------------------------------------------------

SUMMARY
=======
Article Q140595 describes how to enable tool tips for child controls of a
window (including a CDialog).  That article explains how you must call the
CWnd::EnableToolTips function to enable tool tips, and provide a handler for
the TTN_NEEDTEXT tool tip notification.

Although the technique described works for dialogs and views, it does not
work for dialogs derived from CPropertyPage.  You need to override the
default CPropertyPage::PreTranslateMessage in order for the TTN_NEEDTEXT
notifications to be generated.

MORE INFORMATION
================

The CPropertyPage::PreTranslateMessage function always returns FALSE so that
the property sheet will get to handle the message (for Ctrl+TAB etc).
However this bypasses the automatic CWnd handling of tool tips.

To work around this, only call the CPropertyPage::PreTranslateMessage
function for the Ctrl+TAB etc keys.  All other messages can be processed by
the CDialog::PreTranslateMessage function.

Additional Steps to Enable Tool Tips for Child Controls in Property Pages
-------------------------------------------------------------------------

1) Perform the steps outlined in Q140595.

2) Use the Class Wizard to provide a PreTranslateMessage function, and write
an implementation that correctly dispatches to either CPropertyPage or
CDialog as appropriate.

Sample Code
-----------

BOOL CMyPropertyPage::PreTranslateMessage(MSG* pMsg) 
{
 // allow sheet to translate Ctrl+Tab, Shift+Ctrl+Tab,
 //  Ctrl+PageUp, and Ctrl+PageDown
 if (pMsg->message == WM_KEYDOWN && GetAsyncKeyState(VK_CONTROL) < 0 &&
  (pMsg->wParam == VK_TAB ||
   pMsg->wParam == VK_PRIOR ||
   pMsg->wParam == VK_NEXT
    ))
 {
  return CPropertyPage::PreTranslateMessage(pMsg);
 }
 return CDialog::PreTranslateMessage(pMsg);
}

=============================================================================
Roger Onslow,  RogerO@compsys.com.au
=============================================================================


Dean McCrory -- deanm@microsoft.com
Saturday, June 08, 1996

Probably the better fix is to call CWnd::PreTranslateMessage from
CPropertyPage::PreTranslateMessage.

>BOOL CMyPropertyPage::PreTranslateMessage(MSG* pMsg) 
>{
            VERIFY(!CWnd::PreTranslateMessage(pMsg));

            return FALSE;   // CPropertySheet handles
PreTranslateMessage in this case
>}

Later,

// Dean
>----------
>From: 	Roger Onslow/Newcastle/Computer Systems
>Australia/AU[SMTP:Roger_Onslow@compsys.com.au]
>Sent: 	Thursday, June 06, 1996 4:56 AM
>To: 	mfc-l; scot_wingo
>Cc: 	Dave Blatt/Newcastle/Computer Systems Australia/AU
>Subject: 	How to Add Tooltips for Controls to an MFC Property Page
>
>
>Environment: VC++ 4.0 / Win 95
>
>How to Add Tooltips for Controls to an MFC Property Page
>
>PSS ID Number: 
>
>Article last modified on 5-Jun-1996
>
>4.00 4.10
>
>------------------------------------------------------------------------
>-----
>The information in this article applies to:
> - The Microsoft Foundation Classes (MFC) included with:
>   Microsoft Visual C++, 32-bit Edition, versions 4.0 and later
>------------------------------------------------------------------------
>-----
>
>SUMMARY
>=======
>Article Q140595 describes how to enable tool tips for child controls of
>a
>window (including a CDialog).  That article explains how you must call
>the
>CWnd::EnableToolTips function to enable tool tips, and provide a
>handler for
>the TTN_NEEDTEXT tool tip notification.
>
>Although the technique described works for dialogs and views, it does
>not
>work for dialogs derived from CPropertyPage.  You need to override the
>default CPropertyPage::PreTranslateMessage in order for the
>TTN_NEEDTEXT
>notifications to be generated.
>
>MORE INFORMATION
>================
>
>The CPropertyPage::PreTranslateMessage function always returns FALSE so
>that
>the property sheet will get to handle the message (for Ctrl+TAB etc).
>However this bypasses the automatic CWnd handling of tool tips.
>
>To work around this, only call the CPropertyPage::PreTranslateMessage
>function for the Ctrl+TAB etc keys.  All other messages can be
>processed by
>the CDialog::PreTranslateMessage function.
>
>Additional Steps to Enable Tool Tips for Child Controls in Property
>Pages
>------------------------------------------------------------------------
>-
>
>1) Perform the steps outlined in Q140595.
>
>2) Use the Class Wizard to provide a PreTranslateMessage function, and
>write
>an implementation that correctly dispatches to either CPropertyPage or
>CDialog as appropriate.
>
>Sample Code
>-----------
>
>BOOL CMyPropertyPage::PreTranslateMessage(MSG* pMsg) 
>{
> // allow sheet to translate Ctrl+Tab, Shift+Ctrl+Tab,
> //  Ctrl+PageUp, and Ctrl+PageDown
> if (pMsg->message == WM_KEYDOWN && GetAsyncKeyState(VK_CONTROL) < 0 &&
>  (pMsg->wParam == VK_TAB ||
>   pMsg->wParam == VK_PRIOR ||
>   pMsg->wParam == VK_NEXT
>    ))
> {
>  return CPropertyPage::PreTranslateMessage(pMsg);
> }
> return CDialog::PreTranslateMessage(pMsg);
>}
>
>========================================================================
>=====
>Roger Onslow,  RogerO@compsys.com.au
>========================================================================
>=====
>
>
>


Roger Onslow -- Roger_Onslow@compsys.com.au
Tuesday, June 11, 1996

>Probably the better fix is to call CWnd::PreTranslateMessage from
>CPropertyPage::PreTranslateMessage.
>
>>BOOL CMyPropertyPage::PreTranslateMessage(MSG* pMsg) 
>>{
>>            VERIFY(!CWnd::PreTranslateMessage(pMsg));
>>            return FALSE;   // CPropertySheet handles PreTranslateMessage in 
this case
>>}

NO...

We tried that, and tooltip DID appear, BUT....

Behaviour of Ctrl+TAB etc was different from normal property sheets.
The focus went from Tab to Tab ok... BUT THEN to OK button etc.
(ie treated Ctrl+TAB as moving focus amongst all controls on the
property sheet, not just between pages !!)

The solution posted gave consistent handling of Ctrl+TAB.
(ie: CPropertyPage handles Ctrl+TAB, and CWnd everything else)

Roger Onslow

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