mfc, How can a CEdit notify his parent dialog of a change?

by **R2Vv** » Sat, 29 Jan 2005 21:49:02 GMT

Hi to all,

I'm using an edit box as a protected user input. The edit box is by default
read-only and it allows only digits to be entered.

When the user wants to write into the edit box, he has to double click on it
to enable writing (read-only = FALSE). When he finishes entering his info, he
has to double click on the edit box again to apply the entered value. The
edit box will then switch back to read-only.

I'm doing this by creating a new class CRoEdit (for read-only) derived from
CEdit which all it does is catch the double click and set the read-only
accordingly. Here's the only member function in CRoEdit:

void CRoEdit::OnLButtonDblClk(UINT nFlags, CPoint point)
{
if ((GetStyle() & ES_READONLY) == ES_READONLY)
SetReadOnly(FALSE);
else
{
// The user has finished entering his value. Set the edit box back
to read-only
// and inform the parent dialog of a change in the value.
SetReadOnly(TRUE);
}
CEdit::OnLButtonDblClk(nFlags, point);
}

My problem is that I don't know how can I make the CRoEdit class notify the
CDialog class (which contains the edit control) that a new value has been
entered so that CDialog could read it with "m_roEdit.GetWindowText()" to get
the value entered.

I appreciate any help or suggestions.

Thanks,

Geo

by **Scott McPhillips [MVP]** » Sat, 29 Jan 2005 22:49:54 GMT

Hi Geo,
Define a custom message
#define UWM_GEO_MESSAGE (WM_APP + 1)

..and send it to the parent dialog like this:
GetParent()->SendMessage(UWM_GEO_MESSAGE, 0, 0);

The parent dialog message map will need
ON_MESSAGE(UWM_GEO_MESSAGE, OnGeoMessage)

and the message handler must match this prototype:
LRESULT CxxDlg::OnGeoMessage(WPARAM w, LPARAM l)

--
Scott McPhillips [VC++ MVP]

by **R2Vv** » Sat, 29 Jan 2005 23:15:05 GMT

Thanks a lot Scott, it's working fine although by mistake I used:
SendMessage(UWM_GEO_MESSAGE, 0, 0);

instead of:
GetParent()->SendMessage(UWM_GEO_MESSAGE, 0, 0);

Do you think it's important?

Thanks again,
Geo

by **Ajay Kalra** » Mon, 31 Jan 2005 00:48:33 GMT

When you use GetParent()->SendMessage, you are sending it to the parent,
thats your goal. When you use it simply as SendMessage, you are sending it
to the control itself(thats not what you want).

notify the
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mfc, How can a CEdit notify his parent dialog of a change?

mfc >> How can a CEdit notify his parent dialog of a change?

mfc >> How can a CEdit notify his parent dialog of a change?

mfc >> How can a CEdit notify his parent dialog of a change?

How can a CEdit notify his parent dialog of a change?