C / C++ / MFC

19-Sep-02 1:55

One way would be to override PreTranslateMessage in your dialog and catching the enter key:

BOOL CMyDialog::PreTranslateMessage( MSG* pMSG )
{
    if ( pMSG->message == VM_KEYDOWN && pMSG->wParam == VK_RETURN )
    {
        //It's the enter key - check if your editbox has the focus:
        if ( GetFocus( ) == &m_wndMyEditBoxThatIWantToCatchTheEnterKeyIn )
        {
            //Do stuff here...
        }
    }
}
//Code written from the top of my head so it might not compile :-)

Of course there are many other ways also.

Hope this helps,
- d a b s -

Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

ns19-Sep-02 2:04

19-Sep-02 2:04

Okay. I already have in my prestranslate message:

if ((pMsg->message == WM_KEYDOWN))// && (pMsg->hwnd == m_hWnd))
{
    if (pMsg->wParam == VK_RETURN)
    {
        return TRUE;
    }
}

and dont know why or how (can you explain?), but it prevents the Cdialog from getting dismiised with an Enter. If I do your code idea, will the dialog vanish after pressing Enter? Thats what I want to happen, but if the user presses enter any other place other than the editbox , i dont want the dialog to vanish. Also a blank Cedit should not be able to be dismissed with Enter. Will your code if I replace mine with yours, so that? Or do I have to do (modified your code in red):

if ( pMSG->message == VM_KEYDOWN && pMSG->wParam == VK_RETURN )

{ //It's the enter key - check if your editbox has the focus:
if ( GetFocus( ) == &m_wndMyEditBoxThatIWantToCatchTheEnterKeyIn )
{ //Do stuff here... }

return TRUE
}

Thanks,
ns

Thanks,
ns

dabs19-Sep-02 2:13

19-Sep-02 2:13

Yes this should work - only return TRUE if your editbox has the focus when the enter key is pressed.

Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

ns19-Sep-02 2:27

19-Sep-02 2:27

Wait , wait.....I'm not there yet (sorry).

The way it originally was, what exactly did trapping those messages do? The dialog only vanished when I pressed DONE ( with EndDialog). SO the return TRUE seems to make my dialog unresponsive to any ENTERs....

Sorry to bother you but can you please explain what exactly is happening when TRUE is returned? MSDN says:

Return value : Nonzero if the message was translated and should not be dispatched; zero if the message was not translated and should be dispatched.

so when TRUE is returned, this means ignore these keystrokes. SO if I do a return TRUE within your focus checking if condition, this means my enter will be ignored? .....confused. I thought it would be:

if (focusonedit)

 {do stuff}

else

return TRUE

What I understand you are saying is

if (focusonedit)

 {
    do stuff

    return TRUE
}

Want the dialog to respond to Enter only when focus is on edit, and I am confused as to which one to use (the fisrt or second
of the two above.

Appreciate your help greatly.
ns

Thanks,
ns

avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Arjan Schouten19-Sep-02 3:23

Arjan Schouten

19-Sep-02 3:23

Try them both and see what happens! (hint: RETURN TRUE discards the keypress)

You'll learn more by trying yourself!

Good luck! Smile | :)

van Padoea!

Joan M19-Sep-02 1:01

Joan M

19-Sep-02 1:01

hello,

first of all let me thank you in advance, excuse me for my english, it's not my best.

I have some property pages that have ListCtrls (in report mode), and I'm editing the ListCtrl subitems, in order to begin the edition I want to allow the user to double click them (what is easy) and to hit the "enter" key in order to begin or finish the edition.

I've seen that there's a function that meets my needs:

OnReturnLctrl(NMHDR* pNMHDR, LRESULT* pResult)

this function works as the double click function (it use the same parameters).

The problem arises when I press the enter key, because I get the property sheet closed.

Could you give me an advice in order to be able to use the OnReturnLctrl(NMHDR* pNMHDR, LRESULT* pResult) and not to get out of the property page when I press the enter key?

NOTE
I would not like to remove the default buttons.

Re: avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Arjan Schouten19-Sep-02 1:12

Arjan Schouten

19-Sep-02 1:12

Return FALSE in CMyPropertyPage::OnApply()

thus

<br />
BOOL CMyPropertyPage::OnApply() <br />
{<br />
      return FALSE;<br />
}<br />

van Padoea

Re: avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Steve S19-Sep-02 1:48

Steve S

19-Sep-02 1:48

This is also a general issue with dialogs that have controls on which support in-place edit. The real trick is not to override OnApply or OnOK (in the dialog case), but to use PreTranslateMessage at the control's parent window level, the dialog or property page.

There's an article on this in the controls/List Control or Tree Control section of CodeProject that describes how to do this, but I don't have the reference to hand.

Steve S
[This signature space available for rent]

Re: avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Joan M19-Sep-02 3:55

Joan M

19-Sep-02 3:55

Yes, but if I use PreTranslateMessage I canot call the event that I need to handle, at least I don't know how to do it...

In the PreTranslateMessage I have tried:

<br />
if ((pMsg->message == WM_KEYDOWN) && ((int)pMsg->wParam == VK_RETURN))<br />
	{<br />
		if (pMsg->hwnd != this->m_cLCtrlIntroduccio.GetSafeHwnd())<br />
		{<br />
			return TRUE;<br />
		}<br />
	}<br />

in order not to be able to process the enter key in any other control.

but then I also cannot reach:

<br />
MyClass::OnReturnLctrlIntroduccio(NMHDR* pNMHDR, LRESULT* pResult) /*event of the CListCtrl class */<br />
{<br />
	AfxMessageBox("return detected in the ListCtrl");<br />
	*pResult = 0;<br />
}<br />

because the property sheet disappears in the same way...

Re: avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Steve S19-Sep-02 4:40

Steve S

19-Sep-02 4:40

Ah. What I meant was that you detect that the input message is aimed at your edit window, and send the message normally (there are different ways to do this) before returning TRUE.

if (pMsg->message == WM_KEYDOWN &&
pMsg->wParam == VK_RETURN || pMsg->wParam == VK_ESCAPE)
{
CEdit* edit = m_TreeCtrl.GetEditControl();
if (edit)
{
edit->SendMessage(WM_KEYDOWN, pMsg->wParam, pMsg->lParam);
return TRUE;
}
}

You can also replace the SendMessage with
::TranslateMessage(pMsg);
::DispatchMessage(pMsg);
if you want to.

This should work as you require.

Sorry for any confusion.

Steve S
[This signature space available for rent]

Re: avoid to close the property sheet when the user press return, handling return key in a ListCtrl...

Joan M19-Sep-02 5:10

Joan M

19-Sep-02 5:10

Great!

sorry, this was really clear, it's my fault, tonight I haven't sleeped and I'm very tired Sleepy | :zzz:

thank you very much!

convert CString to a _bstr_t - how to?

ns19-Sep-02 1:00

19-Sep-02 1:00

How do I convert a CString to a _bstr_t?

Thanks,
ns

dabs19-Sep-02 1:25

19-Sep-02 1:25

_bstr_t bstrText = L"text";
//You can let CString do the conversion from wchar to char:
CString strText = (LPCWSTR)bstrText;
//or let _bstr_t do it:
CString strText2 = (LPCSTR)bstrText;

Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

ns19-Sep-02 1:31

19-Sep-02 1:31

The other way round:

I have CString a ="abc";

I want to make this a _bstr_t, so that I have:

_bstr_t ab = SOmethingDoneTo (a)

Thanks,
ns

ns19-Sep-02 1:32

19-Sep-02 1:32

Incidentally, whats the L mean here from your snippet?

L"text";

Thanks,
ns

dabs19-Sep-02 1:39

19-Sep-02 1:39

To answer both of your questions:

ns wrote:
Incidentally, whats the L mean here from your snippet?

It means that the hardcoded text shall be interpreted as a string of wchar - not char. In other words:

char* pszText = "this is a text"; //This works
wchar_t* pszwText = L"so is this"; //This works also

char* pszText2 = L"doesn't work"; 
//This generates a compiler error - can't convert from wchar to char

wchar* pszwText2 = "doesn't work either"
//this also generates compiler error.

To answer your other question - to convert from CString to _bstr_t you can use:

CString strText = _T("This is a text");
_bstr_t bstrText = (LPCTSTR)strText;
//Now _bstr_t will construct itself from a LPCTSTR - ususally a const char*

Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

Trollslayer19-Sep-02 1:42

Trollslayer

19-Sep-02 1:42

Here is a code fragment:

void CShelf2Dlg::OutStr(CString Str, int Port)
{
VARIANT va;

va.vt = VT_BSTR; // The variant is storing a string
va.bstrVal = Str.AllocSysString(); // Convert the CString to the VARIANT
Comport[Port]->SetOutput(va); // and output it

}

Elaine (fluffy tigress emoticon)

Would you like to meet my teddy bear ?

ns19-Sep-02 1:53

19-Sep-02 1:53

Well, I did

_bstr_t b_dataBaseName = SysAllocString (dataBaseName);

where dataBaseName is a char* and get the error:

error C2664: 'SysAllocString' : cannot convert parameter 1 from 'char *' to 'const unsigned short *'

Thanks,
ns

dabs19-Sep-02 1:58

19-Sep-02 1:58

This will work but your program will leak memory. ::SysAllocString allocates a BSTR and you are assigning it to a _bstr_t. _bstr_t does not take ownership of the BSTR however so you would have to release it using ::SysFreeString( ).

Yet another way would be to use the USES_CONVERSION macros defined in atlconv.h - your code would then look like:

USES_CONVERSION;

_bstr_t b_databaseName = T2W( dataBaseName );

Hope this helps,
- d a b s -

Wenn ist das Nunstück git und Slotermeyer? Ja! Beierhund das oder die Flipperwaldt gersput!

ns19-Sep-02 2:13

19-Sep-02 2:13

I tried both your ideas, (freeing the bstr also), but I got from the atlconv idea:

error C2664: 'MakeDB' : cannot convert parameter 1 from 'class _bstr_t' to 'unsigned short ** '

I must be doing something incredibly dumb....

	  char* dataBaseName = new char[dataBaseName0.GetLength() +1];

	  strcpy(dataBaseName, dataBaseName0);
	
//	  BSTR b_dataBaseName = SysAllocString (dataBaseName);

	  USES_CONVERSION;
	  
	  _bstr_t b_dataBaseName = T2W( dataBaseName );
	   char* strFile = new char[strFile0.GetLength() +1];

	  strcpy(strFile, strFile0);

//	  _bstr_t b_strFile = SysAllocString (strFile);

	  _bstr_t b_strFile = T2W(strFile);

      _Class1Ptr ptr;
 
       ptr.CreateInstance(__uuidof(Class1));

        ptr->MakeDB( b_strFile, b_dataBaseName);

//	      ptr->MakeDB( LPCTSTR(strFile), LPCTSTR(dataBaseName));

//		SysFreeString (b_dataBaseName);

//		SysFreeString (b_strFile);

                delete[] etc

Thanks for all the help so far....

Thanks,
ns

dabs19-Sep-02 2:17