how to remove "+" before a tree node

hi,

My project is built on windows mobile 5.0 pocket pc,vs2005.I use the following code insert a tree node:
   TVINSERTSTRUCT InsertStruct;
   InsertStruct.hParent  = hParent;
   InsertStruct.hInsertAfter = TVI_LAST;
   InsertStruct.item.mask = TVIF_TEXT |TVIF_IMAGE |TVIF_CHILDREN;
   InsertStruct.item.pszText = FileData.cFileName;
   InsertStruct.item.iImage = 0;
   InsertStruct.item.cChildren = 1;
   InsertItem(&InsertStruct);
That's to say, all the insert nodes have children and so have "+" before them.
But now I need to remove "+" before them ,and I used SetItem function to remove it but the function just delete its children.

Any suggestion on how to remove "+" is appreciated.

Para

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how to remove "+" before a tree node

Amanda Song

Hmmm...

I'm sure your control has the TVS_HASBUTTONS style set Have you tried to use a parent callback instead of setting zero or one in the cChildren member

I assume you are using cChildren = 0 when using SetItem, aren't you
Winterset
Yes, you're right,the tree has TVS_HASBUTTONS style and I use the following code to remove "+":
  TVITEM item  = { 0 };
  item.mask  = TVIF_HANDLE | TVIF_CHILDREN;
  item.hItem  = hRoot ;
  item.cChildren = 0;
  SetItem( &item );
But I can't understand what you say,how to use a parent callback
Morias
The following is the code:
  TV_DISPINFO tvdi;
  tvdi.item.mask   = TVIF_CHILDREN ;
  tvdi.item.hItem   = hCurrent;
  GetItem(&tvdi.item);
  tvdi.item.cChildren = 0;
  SetItem(&tvdi.item);

  HWND hWndParent;
  hWndParent = ::GetParent(m_hWnd);
  if(hWndParent)
  {
   tvdi.hdr.hwndFrom = m_hWnd;
   tvdi.hdr.idFrom  = GetDlgCtrlID(m_hWnd);
   tvdi.hdr.code  = TVN_GETDISPINFO;
   SendMessage(hWndParent, WM_NOTIFY, tvdi.hdr.idFrom,
       (LPARAM)&tvdi);
  }
that's to say ,first set the item's cChildren equal 0,and then send message to its parent to remove "+" .
RonaldS
That's great! Could you post the solution or a link to the solution here This way, we can build FAQS, so other people can benefit from it too!
Tim Heckel
Excellent! I've marked it as answered so people can see for themselves.

Sondre - MSFT Regional Director

I have to say I'm not familiair with the CE SDK, but the help suggests to use I_CHILDRENCALLBACK for the cChildren member. This callback lets you dynamically tell if the member contains children.

I_CHILDRENCALLBACK

The parent window keeps track of whether the item has child items. In this case, when the tree view control needs to display the item, the control sends the parent a TVN_GETDISPINFO message to determine whether the item has child items.

Or is this not supported on CE

LCoder
Thank U very much.
I have tried I_CHILDRENCALLBACK in my project and it doesn't work too,but I find some valuable infomation in the internet with the keyword "I_CHILDRENCALLBACK" ,and now the problem is not a problem.

Para
how to remove "+" before a tree node

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