Help with Tree View

Hi!

I don't seem to get my Tree View running...

every time I try to compile my (very simple) Prog with the Treeview in it, I get the error

Error E2451 simplewin2.c 169: Undefined symbol 'item' in function AddItemToTree

allthough "item" definitely IS a member variable of the TVINSERTITEM struct... I don't know what I'm doing wrong.

(FYI: I'm using the free Borland Commandlinetools, not MSVC.)

And when I get this to work (hopefully, with your help...) I have the next problem right following: I want the Tree View to display the directory structure of the PC... so I need to scan the drives for all directory names and add 'em to the Tree View... how can I do this?

(FYI 2: I'm NOT using MFC, just the "normal" Win32 API)

Of course, it's "TVINSERTSTRUCT" not "TVINSERTITEM" ... but it's typed right in my code so that wasnt the prob, I just made a mistake when writing this post. ;)

Need to see the code to realy help.

Mainly how have you declared the TV_ITEM structure 'item'. It could be that item is another struct and can its members have to be refrenced not the whole ie TVInsert.item.mask (unless you are doing a CopyMemory() )

Or it could be that MS have changed it from TVITEM to TV_ITEM to maintain structure naming conventions and you have old files in your compiler.

It's basically the original example code from msdn:

Code:

---

// AddItemToTree - adds items to a tree-view control.
// Returns the handle to the newly added item.
// hwndTV - handle to the tree-view control.
// lpszItem - text of the item to add.
// nLevel - level at which to add the item.

HTREEITEM AddItemToTree(HWND hwndTV, LPSTR lpszItem, int nLevel)
{
    TVITEM tvi;
    TVINSERTSTRUCT tvins;
    static HTREEITEM hPrev = (HTREEITEM)TVI_FIRST;
    static HTREEITEM hPrevRootItem = NULL;
    static HTREEITEM hPrevLev2Item = NULL;
    HTREEITEM hti;

    tvi.mask = TVIF_TEXT | TVIF_IMAGE
              | TVIF_SELECTEDIMAGE | TVIF_PARAM;

    // Set the text of the item.
    tvi.pszText = lpszItem;
    tvi.cchTextMax = sizeof(tvi.pszText)/sizeof(tvi.pszText[0]);

    // Assume the item is not a parent item, so give it a
    // document image.
    tvi.iImage = g_nDocument;
    tvi.iSelectedImage = g_nDocument;

    // Save the heading level in the item's application-defined
    // data area.
    tvi.lParam = (LPARAM)nLevel;
    tvins.item = tvi;
    tvins.hInsertAfter = hPrev;

    // Set the parent item based on the specified level.
    if (nLevel == 1)
        tvins.hParent = TVI_ROOT;
    else if (nLevel == 2)
        tvins.hParent = hPrevRootItem;
    else
        tvins.hParent = hPrevLev2Item;

    // Add the item to the tree-view control.
    hPrev = (HTREEITEM)SendMessage(hwndTV,
                                  TVM_INSERTITEM,
                                  0,
                                  (LPARAM)(LPTVINSERTSTRUCT)&tvins);

    // Save the handle to the item.
    if (nLevel == 1)
        hPrevRootItem = hPrev;
    else if (nLevel == 2)
        hPrevLev2Item = hPrev;

    // The new item is a child item. Give the parent item a
    // closed folder bitmap to indicate it now has child items.
    if (nLevel > 1)
    {
        hti = TreeView_GetParent(hwndTV, hPrev);
        tvi.mask = TVIF_IMAGE | TVIF_SELECTEDIMAGE;
        tvi.hItem = hti;
        tvi.iImage = g_nClosed;
        tvi.iSelectedImage = g_nClosed;
        TreeView_SetItem(hwndTV, &tvi);
    }

    return hPrev;
}

---

If you are right with your idea that I may have not-up-to-date files in my compiler, what would I have to change (in the commctrl.h??)

Thanks for helping :)

In the commctrl.h file, the 'item' member of TVINSERTSTRUCT is declared as TV_ITEMA, or TVITEM. Find this in your commctrl.h file:

typedef struct _TV_INSERTSTRUCTA {
HTREEITEM hParent;
HTREEITEM hInsertAfter;
TV_ITEMA item;
} TV_INSERTSTRUCTA,*LPTV_INSERTSTRUCTA;
typedef struct _TV_INSERTSTRUCTW {
HTREEITEM hParent;
HTREEITEM hInsertAfter;
TV_ITEMW item;
} TV_INSERTSTRUCTW,*LPTV_INSERTSTRUCTW;

and be sure that the TV_ITEMA and TV_ITEMW lines are in there.

Yes it seems to be quite up-to-date, I think... here's what I got in the commctrl.h of Borland C++ 5.5.1

Code:

---

typedef struct tagTVINSERTSTRUCTA {
    HTREEITEM hParent;
    HTREEITEM hInsertAfter;
#if (_WIN32_IE >= 0x0400)
    union
    {
        TVITEMEXA itemex;
        TV_ITEMA  item;
    } DUMMYUNIONNAME;
#else
    TV_ITEMA item;
#endif
} TVINSERTSTRUCTA, FAR *LPTVINSERTSTRUCTA;

typedef struct tagTVINSERTSTRUCTW {
    HTREEITEM hParent;
    HTREEITEM hInsertAfter;
#if (_WIN32_IE >= 0x0400)
    union
    {
        TVITEMEXW itemex;
        TV_ITEMW  item;
    } DUMMYUNIONNAME;
#else
    TV_ITEMW item;
#endif
} TVINSERTSTRUCTW, FAR *LPTVINSERTSTRUCTW;

---

And, later in the file, there are many declare's that make the use of TV_ITEMA, TVITEMA, TVITEM etc. equivalent... so that doesn't seem to be the cause of my problem... :(

You can't do

tvins.item = tvi;//one whole structure equals another whole structure

must do something like

CopyMemory(&(tvins.item),&tvi,sizeof(TVITEM));

(which is why you should post the code first to stop us guessing at the problem and sending you off after red herrings)

>>I want the Tree View to display the directory structure of the PC

Did you look at listbox with the LB_DIR flag?
To scan the HD you will need to use FindFirstFile(), FindNextFile() and FindClose()

Thanks I solved the problem with the tree view (well, not quite yet, it just won't show the images from the imagelist I made for it... but I'm looking at that now)


Thanks for your advices, tho :D