Drag & Drop dans un CTreeCtrl

Salut,

J'ai franchement du mal avec le drag & drop, mais j'ai fini par trouvé ce que je cherchai : faire un drag & drop dans un CTreeCtrl.
Il a fallu recoller les morceaux parce que tout le code était éparpillé (je remercie quand même l'auteur de ces lignes de codes parce que ça marche).
Donc pour tous ceux qui auraient le même problème je met le code qui marche :

Dans le .h

Code:

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protected:
	CImageList*	m_pDragImage;
	BOOL		m_bLDragging;
	HTREEITEM	m_hitemDrag,m_hitemDrop;
 
	HTREEITEM CopyItem( HTREEITEM hItem, HTREEITEM htiNewParent, 
                                        HTREEITEM htiAfter = TVI_LAST );
 
	virtual void OnItemCopied( HTREEITEM hItem, HTREEITEM hNewItem );
 
	HTREEITEM CopyBranch( HTREEITEM htiBranch, HTREEITEM htiNewParent, 
                                                HTREEITEM htiAfter = TVI_LAST);

Dans le .cpp

Code:

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CMyTreeCtrl::CMyTreeCtrl()
{
	m_pDragImage = NULL;
	m_hitemDrag = NULL;
	m_hitemDrop = NULL;
	m_bLDragging = FALSE;
}
 
 
// CopyItem             - Copies an item to a new location
// Returns              - Handle of the new item
// hItem                - Item to be copied
// htiNewParent         - Handle of the parent for new item
// htiAfter             - Item after which the new item should be created
HTREEITEM CMyTreeCtrl::CopyItem( HTREEITEM hItem, HTREEITEM htiNewParent, 
                                        HTREEITEM htiAfter /*= TVI_LAST*/ )
{
        TV_INSERTSTRUCT         tvstruct;
        HTREEITEM                       hNewItem;
        CString                         sText;
 
        // get information of the source item
        tvstruct.item.hItem = hItem;
        tvstruct.item.mask = TVIF_CHILDREN | TVIF_HANDLE | 
                                TVIF_IMAGE | TVIF_SELECTEDIMAGE;
        GetItem(&tvstruct.item);  
        sText = GetItemText( hItem );
 
        tvstruct.item.cchTextMax = sText.GetLength();
        tvstruct.item.pszText = sText.LockBuffer();
 
        // Insert the item at proper location
        tvstruct.hParent = htiNewParent;
        tvstruct.hInsertAfter = htiAfter;
        tvstruct.item.mask = TVIF_IMAGE | TVIF_SELECTEDIMAGE | TVIF_TEXT;
        hNewItem = InsertItem(&tvstruct);
        sText.ReleaseBuffer();
 
        // Now copy item data and item state.
        SetItemData( hNewItem, GetItemData( hItem ));
        SetItemState( hNewItem, GetItemState( hItem, TVIS_STATEIMAGEMASK ), 
                                                        TVIS_STATEIMAGEMASK );
 
        // Call virtual function to allow further processing in derived class
        OnItemCopied( hItem, hNewItem );
 
        return hNewItem;
}
 
 
void CMyTreeCtrl::OnItemCopied(HTREEITEM /*hItem*/, HTREEITEM /*hNewItem*/ )
{
        // Virtual function 
}
 
 
// CopyBranch           - Copies all items in a branch to a new location
// Returns              - The new branch node
// htiBranch            - The node that starts the branch
// htiNewParent - Handle of the parent for new branch
// htiAfter             - Item after which the new branch should be created
HTREEITEM CMyTreeCtrl::CopyBranch( HTREEITEM htiBranch, HTREEITEM htiNewParent, 
                                                HTREEITEM htiAfter /*= TVI_LAST*/ )
{
        HTREEITEM hChild;
 
        HTREEITEM hNewItem = CopyItem( htiBranch, htiNewParent, htiAfter );
        hChild = GetChildItem(htiBranch);
        while( hChild != NULL)
        {
                // recursively transfer all the items
                CopyBranch(hChild, hNewItem);  
                hChild = GetNextSiblingItem( hChild );
        }
        return hNewItem;
}
 
void CMyTreeCtrl::OnBegindrag(NMHDR* pNMHDR, LRESULT* pResult) 
{
	NM_TREEVIEW* pNMTreeView = (NM_TREEVIEW*)pNMHDR;
	*pResult = 0;
 
	m_hitemDrag = pNMTreeView->itemNew.hItem;
	m_hitemDrop = NULL;
 
	m_pDragImage = CreateDragImage(m_hitemDrag);  // get the image list for dragging
	// CreateDragImage() returns NULL if no image list
	// associated with the tree view control
	if( !m_pDragImage )
		return;
 
	m_bLDragging = TRUE;
	m_pDragImage->BeginDrag(0, CPoint(-15,-15));
	POINT pt = pNMTreeView->ptDrag;
	ClientToScreen( &pt );
	m_pDragImage->DragEnter(NULL, pt);
	SetCapture();
}
 
void CMyTreeCtrl::OnMouseMove(UINT nFlags, CPoint point) 
{
	HTREEITEM	hitem;
	UINT		flags;
 
	if (m_bLDragging)
	{
		POINT pt = point;
		ClientToScreen( &pt );
		CImageList::DragMove(pt);
		if ((hitem = HitTest(point, &flags)) != NULL)
		{
			CImageList::DragShowNolock(FALSE);
			SelectDropTarget(hitem);
			m_hitemDrop = hitem;
			CImageList::DragShowNolock(TRUE);
		}
	}
 
	CTreeCtrl::OnMouseMove(nFlags, point);
}
 
void CMyTreeCtrl::OnLButtonUp(UINT nFlags, CPoint point) 
{
	CTreeCtrl::OnLButtonUp(nFlags, point);
 
	if (m_bLDragging)
	{
		m_bLDragging = FALSE;
		CImageList::DragLeave(this);
		CImageList::EndDrag();
		ReleaseCapture();
 
		delete m_pDragImage;
 
		// Remove drop target highlighting
		SelectDropTarget(NULL);
 
		if( m_hitemDrag == m_hitemDrop )
			return;
 
		// If Drag item is an ancestor of Drop item then return
		HTREEITEM htiParent = m_hitemDrop;
		while( (htiParent = GetParentItem( htiParent )) != NULL )
		{
			if( htiParent == m_hitemDrag ) return;
		}
 
		Expand( m_hitemDrop, TVE_EXPAND ) ;
 
		HTREEITEM htiNew = CopyBranch( m_hitemDrag, m_hitemDrop, TVI_LAST );
		DeleteItem(m_hitemDrag);
		SelectItem( htiNew );
	}
 
}