Question

I’m working on a win32/MFC project.
I have a custom CListCtrl control that I must to add, from time to time, some strings of characters.
I absolutely need to perform some manipulations on items dynamically added to my CListCtrl.

Ultra-Basically, I need to:

1. Detect adding of single elements;
2. Retrieve _single items_ IMMEDIATELY AFTER(ideally, shortly after InsertItem() invocation);
3. Store values of single items in a map, which I will use to perform other manipulations.

I thought about doing this overriding the method DrawItem(). but OnDraw event seems not to be available for my CListCtrl.

Event is never generated.

IMPORTANT: Please note that MyCustomCListCtrl have “On Draw Fixed” property set to True, but “View” property is NOT set as a report.

So, I have decided to handle NW_CUSTOMDRAW event, writing my CustomDraw Handler, as explained here and here:

Here you can view another code example.

Then, I need a way to retrieve single itemIDs from my CListCtrl.
More precisely, I need a way to get single item IDs from NMHDR struct.

How can I do this?
I am only able to obtain the ID of the LAST item that I have added.
I am sure it’s a simple mistake I can’t find.

A sample piece of code below:

Source of Dialog that contains CList Ctrl:

/* file MyDlg.cpp */

#include "stdafx.h"
#include "MyDlg.h"

// MyDlg dialog

IMPLEMENT_DYNAMIC(MyDlg, CDialog)

MyDlg::MyDlg(CWnd* pParent)
    : CDialog(MyDlg::IDD, pParent)
{
}

MyDlg::~MyDlg()
{
}

void MyDlg::DoDataExchange(CDataExchange* pDX)
{
    CDialog::DoDataExchange(pDX);
    DDX_Control(pDX, IDC_LIST1, listView); /* listView is a MyCustomCListCtrl object */
}

BEGIN_MESSAGE_MAP(MyDlg, CDialog)
    ON_BN_CLICKED(IDC_BUTTON1, &MyDlg::OnBnClickedButton1) 
END_MESSAGE_MAP()

BOOL MyDlg::OnInitDialog()
{
    CDialog::OnInitDialog();
    return TRUE;
}

/* OnBnClickedButton1 handler add new strings to MyCustomCListCtrl object */

void MyDlg::OnBnClickedButton1()
{
    listView.InsertItem(0, "Hello,");
    listView.InsertItem(1, "World!");
}

My Custom CList Ctrl source:

/* file MyCustomCListCtrl.cpp */

#include "stdafx.h"
#include "MyCustomCListCtrl.h"

MyCustomCListCtrl::MyCustomCListCtrl()
{
}

MyCustomCListCtrl::~MyCustomCListCtrl()
{
}

BEGIN_MESSAGE_MAP(MyCustomCListCtrl, CListCtrl)
    //{{AFX_MSG_MAP(MyCustomCListCtrl)
    //}}AFX_MSG_MAP
    // ON_WM_DRAWITEM()                             /* WM_DRAWITEM NON-AVAILABLE */
    ON_NOTIFY_REFLECT(NM_CUSTOMDRAW, OnCustomDraw)
END_MESSAGE_MAP()

// 'Owner Draw Fixed' property is already TRUE
/*  void CTranslatedCListCtrl::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
    bool inside = true; /* Member function removed: I never enter here... */
}  */

void MyCustomCListCtrl::OnCustomDraw(NMHDR* pNMHDR, LRESULT* pResult)
{
    /* Here, I must retrieve single strings added to my MyCustomCListCtrl object */

    LPNMLISTVIEW plvInfo = (LPNMLISTVIEW)pNMHDR;
    LVITEM lvItem;

    lvItem.iItem = plvInfo->iItem;          /* Here I always get _the same_ ID: ID of last element...*/
    lvItem.iSubItem = plvInfo->iSubItem;    // subItem not used, for now...

    int MyID = 0;

    this->GetItem(&lvItem); // There mai be something error here?
    MyID = lvItem.iItem;

    CString str = this->GetItemText(MyID, 0); /* ...due to previous error, here I will always get the last string I have added("World!") */

    // Immediately after obtaining ALL IDS, I can Do My Work

    *pResult = 0;
}

Any help is appreciated!

P.S.
Please do not give me tips like:

1. Set your “Own Draw Fixed” Property to True;
2. Check you have inserted the line “ON_WMDRAWITEM()”
3. Convert your CListCtrl as a report;

I have already tried everything… 🙂

Thanks to all!

IT

Answer 1

first of all… Thank you wasted your precious time with this stupid question.
I never found anything about LVN_INSERT event.
I write scientific software(most on Linux platform); I am not a long-time Win32 developer, so I don’t know Win32 APIs in depth.
I have modified source file of MyCustomCListCtrl class, as you have suggested.
Code below seems to be the best( and faster )way to achieve what I want:

    /* file MyCustomCListCtrl.cpp */

    #include "stdafx.h"
    #include "MyCustomCListCtrl.h"

    MyCustomCListCtrl::MyCustomCListCtrl()
    {
    }

    MyCustomCListCtrl::~MyCustomCListCtrl()
    {
    }

    BEGIN_MESSAGE_MAP(MyCustomCListCtrl, CListCtrl)
        //{{AFX_MSG_MAP(MyCustomCListCtrl)
        //}}AFX_MSG_MAP
        ON_NOTIFY_REFLECT(LVN_INSERTITEM, OnLvnInsertItem)
    END_MESSAGE_MAP()

    ...

    afx_msg void CTranslatedListCtrl::OnLvnInsertItem(NMHDR* pNMHDR, LRESULT* pResult)
    {
        LPNMLISTVIEW plvInfo = (LPNMLISTVIEW)pNMHDR;
        CString str = this->GetItemText(plvInfo->iItem, 0);

        // Add Some Logic

        *pResult = 0;
    }

Can You confirm?
From what I can see, it seems to work. 🙂
Thanks again!

IT