C / C++ / MFC

Thanks UKM_Student I'm looking at code blocks right now

11-Sep-09 8:11

im not sure about that.Im using codeblocks btw,quite ez to use ^_^

gordon305611-Sep-09 8:37

gordon3056

11-Sep-09 8:37

I think its a tribute to The Code Project members that I an absolute beginner can get any help at all. Thank you

Odd bug in CMFCToolbarComboBoxButton class

Santanu Lahiri11-Sep-09 5:17

Santanu Lahiri

11-Sep-09 5:17

Hello,

I am trying to use this control in a toolbar. For the most part the code works. However, I am running into this odd problem that I am getting partial text back when I call GetText.

The app requires that when I click a different button in the toolbar, I check the combo box and retrieve the text from it for processing. That is when this bug surfaces. The last character is getting truncated. If I retrieve the text in response to the Enter key handler for the combo box, I get the full text using the same GetText call.

Here is the code...most all of it is lifted from the samples.

CObList listButtons;
if (CMFCToolBar::GetCommandButtons(ID_EDT_FIND_NDC, listButtons) > 0)
{
    for (POSITION posCombo = listButtons.GetHeadPosition();
    pSrcCombo == NULL && posCombo != NULL; )
    {
       CMFCToolBarComboBoxButton* pCombo = DYNAMIC_DOWNCAST(CMFCToolBarComboBoxButton, listButtons.GetNext(posCombo));
       if (pCombo != NULL) pSrcCombo = pCombo;
    }
}

if (pSrcCombo != NULL)
{
ASSERT_VALID(pSrcCombo);

LPCTSTR lpszSelItem = pSrcCombo->GetText();
...
}

So if the combo box has the text '1234567890', I am getting back '123456789' in one case, and '1234567890' in another case, depending on whether I press the other button or press the Enter key.

Has anyone encountered this, and can someone suggest a solution?

Thanks for your time.

Re: Odd bug in CMFCToolbarComboBoxButton class

PatrikE20-Oct-09 4:42

PatrikE

20-Oct-09 4:42

I just encountered the same problem here!
No solution so far.
It is so frustrating to work with this feature pack...

Re: Odd bug in CMFCToolbarComboBoxButton class [modified]

Santanu Lahiri20-Oct-09 10:00

Santanu Lahiri

20-Oct-09 10:00

Yes, I finally got frustrated enough to think up alternatives. I had already coded to find the CMFCToolbarComboBoxButton object (Code from MSDN actually), so now I went ahead and code along the following lines:

if (pSrcCombo != NULL)
{
    ASSERT_VALID(pSrcCombo);
    CMFCToolBarComboBoxEdit *pEdit = (CMFCToolBarComboBoxEdit *) pSrcCombo->GetEditCtrl();
    if (pEdit)
    {
        CString strSelItem=_T("");
        pEdit->GetWindowText (strSelItem);
        pSrcCombo->AddItem (strSelItem);
        ...
    }
}

Using the Edit Control seems to have solved the problem for me. At the MFCToolbarComboBoxButton level, there is no option for a fix that I have found. Perhaps subclassing the control and intercepting the GetText() call may work, but I have not tried it.

modified on Tuesday, October 20, 2009 4:07 PM

SOLUTION!!: Odd bug in CMFCToolbarComboBoxButton class

PatrikE20-Oct-09 5:27

PatrikE

20-Oct-09 5:27

At least this works for me:

In the Code, where a character is truncated replace the call to pSrcCombo->GetText() with something like this:

CComboBox* a_pComboBox(pSrcCombo->GetComboBox());
ASSERT(a_pComboBox);
CString a_strAddressTextInCombo;
a_pComboBox->GetWindowText(a_strAddressTextInCombo);

Maybe in your code you have to distinguish somehow where the call comes from...
Or you could try if the above code works for both scenarios.

Hope I could help,
Patrik

Re: SOLUTION!!: Odd bug in CMFCToolbarComboBoxButton class

Santanu Lahiri20-Oct-09 10:07

Santanu Lahiri

20-Oct-09 10:07

Yes, a code sample in the MSDN website gives details on how to identify the control that you are using.

CMFCToolBarComboBoxButton* pSrcCombo = NULL;

CObList listButtons;
if (CMFCToolBar::GetCommandButtons(ID_EDT_FIND_NDC, listButtons) > 0)
{
    for (POSITION posCombo = listButtons.GetHeadPosition();
        pSrcCombo == NULL && posCombo != NULL;)
    {
        CMFCToolBarComboBoxButton* pCombo = DYNAMIC_DOWNCAST(CMFCToolBarComboBoxButton, listButtons.GetNext(posCombo));

        if (pCombo != NULL && CMFCToolBar::IsLastCommandFromButton(pCombo))
        {
            pSrcCombo = pCombo;
        }
    }
}

How to unlock locked file using Win32 API? [modified]

JoeSchmoe00711-Sep-09 4:55

JoeSchmoe007

11-Sep-09 4:55

My problem is similar to the one described here:

http://www-01.ibm.com/support/docview.wss?rs=1079&context=SS2KS6&dc=DB520&uid=swg21230924

In our application we have DLL that is used to write information to Event
Log. Problem is when I need uninstall/upgrade our application this DLL is
often locked after our application is shut down and it requires computer reboot which is undesirable.

For what it's worth - our application is a service. All other .DLL/.EXE files are successfully deleted by uninstall after service is stopped. Or they can be deleted manually if service is stopped.

I know there is a way to unlock/delete this file because this is what
Unlocker application does (http://ccollomb.free.fr/unlocker/)

Does anyone have any ideas on how this is achieved using Windows API?

modified on Friday, September 11, 2009 11:30 AM

Re: How to unlock locked file using Win32 API?

David Crow11-Sep-09 5:17

File is still locked after application is shut down.

11-Sep-09 5:17

JoeSchmoe007 wrote:
Does anyone have any ideas on how this is achieved using Windows API?

How about shutting down your application?

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

JoeSchmoe00711-Sep-09 5:30

JoeSchmoe007

11-Sep-09 5:30

File is still locked after application is shut down. I edited original post to reflect that. For what it's worth - our application is a service.

Re: File is still locked after application is shut down.

David Crow11-Sep-09 5:58

Re: File is still locked after application is shut down.

11-Sep-09 5:58

JoeSchmoe007 wrote:
File is still locked after application is shut down.

Then some other process is using it, or your application is still running.

Nemanja Trifunovic11-Sep-09 8:08

Nemanja Trifunovic

11-Sep-09 8:08

You can use Process Explorer (run it without installation wrom live sysinternals site[^]) to find out which process is holding your file.

Programming Blog

utf8-cpp

Re: How to unlock locked file using Win32 API?

Stuart Dootson11-Sep-09 21:37

Stuart Dootson

11-Sep-09 21:37

There is a way to forcibly close handles - because Process Explorer can do it.

However, in this situation, you should use MoveFileEx[^] with the MOVEFILE_DELAY_UNTIL_REBOOT flag and a NULL destination filename and Windows will perform the file deletion at the next boot time, before any applications have started to lock the file.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: How to unlock locked file using Win32 API?

kilt14-Sep-09 2:21

kilt

14-Sep-09 2:21

Just close the handle remotely (classic and official method, Win32 (news://comp.os.ms-windows.programmer.win32) since 90's..)

Beginner's Question 2

UKM_Student11-Sep-09 4:37

11-Sep-09 4:37

Hmm guys,is it possible to display number1+ number2+number3?

Eg,if a program prompts a user to input 3 numbers,N1,N2 and N3,is it possible for the program to display N1+N2+N3?As far as i know,we can use a while loop to straight away give us the final answer for N1+N2+N3.

To make it clear,if i input 5 as N1,10 as N2 and 15 as N3,can we make the program display
"total=5+10+15=30" instead of "total=30"?

Can someone guide me on this. xD

David Crow11-Sep-09 4:41

11-Sep-09 4:41

UKM_Student wrote:
As far as i know,we can use a while loop to straight away give us the final answer for N1+N2+N3.

That would be the wrong thing to use.

UKM_Student wrote:
To make it clear,if i input 5 as N1,10 as N2 and 15 as N3,can we make the program display
"total=5+10+15=30" instead of "total=30"?

See here.

UKM_Student11-Sep-09 4:44

11-Sep-09 4:44

Erm yeah that was a response to my earlier question,what about this one Blush | :O

This question is asking whether can we display the value(s) we take and then adding them up instead of getting a final answer right away o-o

David Crow11-Sep-09 4:48

11-Sep-09 4:48

UKM_Student wrote:
Erm yeah that was a response to my earlier question,what about this one

The same response applies. You can have multiple values for a single cout statement.

UKM_Student11-Sep-09 4:56

11-Sep-09 4:56

Erm im not trying to display exactly the numbers lol.Go see the program i wrote in the other page xD

UKM_Student11-Sep-09 4:55

11-Sep-09 4:55

why is it wrong?For eg.

#include<iostream>
using namespace std;
int main()
{
int total=0,count=0,number;

while(count<5)
{
cout<<"Input 5 numbers.";
cin>>number;
total=total+number;
count++;
}
cout<<"Total is "<<total<<endl;

return 0;
}

From here we can see that the compiler adds up all the 5 numbers.My question is how should i put it so it would display" total: N1+N2+N3+N4+N5=XX "instead of adding all the numbers up then display "total:XX"

David Crow11-Sep-09 5:13

11-Sep-09 5:13

UKM_Student wrote:
why is it wrong?

Because you wanted to use a while() loop to sum N1, N2, and N3. Given:

int N1, N2, N3;
while ()
{
    // what would go here?
}

How would that work?

UKM_Student wrote:
cout<<"Input 5 numbers.";

This should probably go outside the while() loop.

UKM_Student wrote:
My question is how should i put it so it would display" total: N1+N2+N3+N4+N5=XX "instead of adding all the numbers up then display "total:XX"

Given that you are not saving number each time through the loop, you can't.

Consider:

int count = 0, number[5];
  
while (count < 5)
{
    cin >> number[count];
    total += number[count];
    count++;
}
  
cout << endl << "total: ";
  
count = 0;
while (count < 5)
{
    cout << number[count];
    if (count < 4)
        cout << '+';
}
  
cout << '=' << total;

UKM_Student11-Sep-09 5:23