Re: how to recive checkbox click event on CDateTimeCtrl?

From:
"AliR" <AliR@online.nospam>
Newsgroups:
microsoft.public.vc.mfc
Date:
Tue, 29 Aug 2006 10:34:08 -0500
Message-ID:
<44f45ed1$0$15197$a8266bb1@reader.corenews.com>
I changed my mind about the way I was notifying the parent about the check
box status changes.

Instead of sending a seperate message to the parent I just add a value to
the dwFlag of pDTChange variable

BOOL CCheckDateTimeCtrl::OnDtnDatetimechange(NMHDR *pNMHDR, LRESULT
*pResult)
{
   LPNMDATETIMECHANGE pDTChange =
reinterpret_cast<LPNMDATETIMECHANGE>(pNMHDR);
   // TODO: Add your control notification handler code here
   *pResult = 0;

   if (!m_Checked && pDTChange->dwFlags == GDT_VALID)
   {
      pDTChange->dwFlags |= 0x2;
      m_Checked = TRUE;
   }
   else if (m_Checked && pDTChange->dwFlags == GDT_NONE)
   {
      pDTChange->dwFlags |= 0x4;
      m_Checked = FALSE;
   }

   return FALSE;
}

This was all the parent window has to do is catch the DTN_DATETIMECHANGE
message and check for these values in the flag

Like this

void CDialogTestDlg::OnDtnDatetimechangeDatetimepicker1(NMHDR *pNMHDR,
LRESULT *pResult)
{
   LPNMDATETIMECHANGE pDTChange =
reinterpret_cast<LPNMDATETIMECHANGE>(pNMHDR);
   // TODO: Add your control notification handler code here
   *pResult = 0;
   if (pDTChange->dwFlags & 0x2)
   {
      MessageBox("It was just checked");
   }
   else if (pDTChange->dwFlags & 0x4)
   {
      MessageBox("It was just unchecked");
   }
}

AliR.

"AliR" <AliR@online.nospam> wrote in message
news:44f45188$0$15176$a8266bb1@reader.corenews.com...

You will have to do a little work yourself. When the control sends you a
DTN_DATETIMECHANGE it will actually tell you when the check box is
unchecked. If the dwFlags member of LPNMDATETIMECHANGE struct that is
passed to DTN_DATETIMECHANGE is GDT_NONE then the user just unchecked the
box.
So all you have to do is, derive a class from CDateTimeCtrl. Have a bool
flag that keeps track of the check state, set it to true by default. Take
over the DTN_DATETIMECHANGE using message reflection. When you detect a
uncheck and the flag says that it was checked before then you know that

they

just unchecked the checkbox, if you get a DTN_DATETIMECHANGE with dwFalgs
set to GDT_VALID and the check flag is false then you know that they just
checked it.

Here is the code:

CheckDateTimeCtrl.h
#pragma once

// CCheckDateTimeCtrl
#define WM_DTN_CHECKCHANGED WM_APP + 100

class CCheckDateTimeCtrl : public CDateTimeCtrl
{
 DECLARE_DYNAMIC(CCheckDateTimeCtrl)

public:
 CCheckDateTimeCtrl();
 virtual ~CCheckDateTimeCtrl();

protected:
   afx_msg BOOL OnDtnDatetimechange(NMHDR *pNMHDR, LRESULT *pResult);

   DECLARE_MESSAGE_MAP()
private:
   BOOL m_Checked;
};

CheckDateTimeCtrl.cpp
// CheckDateTimeCtrl.cpp : implementation file
//

#include "stdafx.h"
#include "CheckDateTimeCtrl.h"

// CCheckDateTimeCtrl

IMPLEMENT_DYNAMIC(CCheckDateTimeCtrl, CDateTimeCtrl)
CCheckDateTimeCtrl::CCheckDateTimeCtrl()
: m_Checked(TRUE)
{
}

CCheckDateTimeCtrl::~CCheckDateTimeCtrl()
{
}

BEGIN_MESSAGE_MAP(CCheckDateTimeCtrl, CDateTimeCtrl)
   ON_NOTIFY_REFLECT_EX(DTN_DATETIMECHANGE, OnDtnDatetimechange)
END_MESSAGE_MAP()

// CCheckDateTimeCtrl message handlers

BOOL CCheckDateTimeCtrl::OnDtnDatetimechange(NMHDR *pNMHDR, LRESULT
*pResult)
{
   LPNMDATETIMECHANGE pDTChange =
reinterpret_cast<LPNMDATETIMECHANGE>(pNMHDR);
   // TODO: Add your control notification handler code here
   *pResult = 0;

   if (!m_Checked && pDTChange->dwFlags == GDT_VALID)
   {
      MessageBox("Checked");
      if (GetParent())
      {
         GetParent()->SendMessage(WM_DTN_CHECKCHANGED,1);
      }
      m_Checked = TRUE;
   }
   else if (m_Checked && pDTChange->dwFlags == GDT_NONE)
   {
      MessageBox("Unchecked");
      if (GetParent())
      {
         GetParent()->SendMessage(WM_DTN_CHECKCHANGED,0);
      }
      m_Checked = FALSE;
   }

   return FALSE;
}

AliR.

"rsobies" <rsobies@discussions.microsoft.com> wrote in message
news:DD89522D-A097-4704-AB20-4D3B047D9BA4@microsoft.com...

this message is also send when a user change a date or when a user swich
betwean months. i want to know when exactly the checkbox is clicked

"AliR" wrote:

Well it does send a DTN_DATETIMECHANGE message.

AliR.

"rsobies" <rsobies@discussions.microsoft.com> wrote in message
news:C942CA85-9A0D-4D42-AA14-34901FFA192A@microsoft.com...

is there any way to handel this event?

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