asked on

Sorting listbox items !

How can I sort the items of a listbox which was not created with LBS_SORT style.

I have try this :

m_MyListBox.ModifyStyle(0, LBS_SORT); // DOESN'T WORK

Can someone help me.

In my application, I have a listbox which is not sorted. A button called "SORT", must sort the listbox items.

jhance

There may be another way that I'm not aware of but what I've done in the past is to just read out all of the items into a temporary location, call ModifyStyle to turn on sort, call ResetContent to clear it out and then finally add all the items back to the control.

ghimireniraj

m_MyListBox.ModifyStyle(0, LBS_SORT); // DOESN'T WORK

Why doesn't it work?

jhance

It does work, it just doesn't re-sort a filled listbox. At least I've not seen it do that.

You have any ideas?

mikeblas

> It does work, it just doesn't re-sort a filled listbox.

Exactly.

You could also consider having two boxes; one with LBS_SORT and the other without. Do all operations to both boxes, but only show one depending on whatever makes you toggle.

..B ekiM

mike_marquet

ASKER

It doesn't work.

Here's the function :

void MyDlg::OnPB_AlphaSort()
{
CStringArray ArrayToSort;

for (int I=0; I<m_MyListBox.GetCount(); I++)
{
CString str;

m_LB_MyListBox.GetText(I, str);

ArrayToSort.Add(str);
}

m_LB_MyListBox.ResetContent();

m_LB_MyListBox.ModifyStyle(0, LBS_SORT);

for (I=0; I<ArrayToSort.GetSize(); I++)
{
CString str = ArrayToSort.GetAt(I);

m_LB_MyListBox.AddString(str);
}

//m_LB_MyListBox.ModifyStyle(LBS_SORT, 0);
}

ASKER CERTIFIED SOLUTION

mikeblas

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mike_marquet

ASKER

I have make it so :

int compare(const void *arg1, const void *arg2)
{
return _stricmp( (char *)arg1, (char *)arg2 );
}

void MyDlg::OnPB_AlphaSort()
{
int iCount = m_MyListBox.GetCount();
char (*ArrayToSort)[255] = new char [iCount] [255];

memset(ArrayToSort, 0, 255 * iCount);

for (int I=0; I<iCount; I++)
{
CString str;

m_MyListBox.GetText(I, str);

strcpy(ArrayToSort[I], str);
}

qsort( (void *)ArrayToSort, (size_t)iCount, 255, compare);

m_MyListBox.ResetContent();

for (I=0; I<iCount; I++)
{
m_MyListBox.AddString(ArrayToSort[I]);
}

delete [] ArrayToSort;
}

abancroft

And the list box was originally created with LBS_HASSTRINGS?

mikeblas

So, then you'll need to create two controls, or recreate the ListBox after you've unloaded it.

..B ekiM

mike_marquet

ASKER

The listbox is create without using owner draw, therefore the hasstring is not accessible but I think in non owner draw mode, the hasstring is set as default.

mikeblas

Is there some reason you don't want to create two controls, mike_marquet?

..B ekiM

mike_marquet

ASKER

No, but it is much easier to use one control and sort or not this only control.

mikeblas

I'm not sure that's true. You'll have to do the sorting maually, since you can't retroactively apply the LBS_SORT style.

Will you be changing the control back to unsorted? What does that mean? Unsorted usually means that there's actually some other order; just that the order isn't alphabetical.

Maybe you should always have LBS_SORT, but do your own item comparison and switch the item comparison routine so that it sorts along the two different orders you like.

..B ekiM

mike_marquet

ASKER

In my application, a have a SORT button. When I push it, the listbox items must be sorted. After it, I can add some more items which will than not be sorted.

mikeblas

You can do that without adding and removing the LBS_SORT style. Just keep the style and manage the comparisons yourself.

..B ekiM

mike_marquet

ASKER

OK, Thanks, I will try it so.

Netminder

Netminder

Delete request rejected. Comment force accepted.

Netminder
CS Moderator, EE