HTREEITEM CTreeViewEx::GetDropItem(eTYPE_DROPPING & eDroppingPos)
{
CTreeCtrl &omTreeCtrl = GetTreeCtrl();
CPoint omCurrentPoint;
GetCursorPos(&omCurrentPoint);
ScreenToClient(&omCurrentPoint);
UINT flags;
HTREEITEM hDroppingItem = omTreeCtrl.HitTest(omCurrentPoint, &flags);
eDroppingPos = GetDroppingPosition(flags);
if(IsItemCanDropOn(m_hDraggingItemgedItem, hDroppingItem) == FALSE)
{
eDroppingPos = NO_DROPPING;
}
if(hDroppingItem)
{
m_pomDragImageList->DragLeave(&omTreeCtrl);
omTreeCtrl.SelectDropTarget(hDroppingItem);
// Make sure the surrounding items are visible, too
// This will scroll the tree if necessary.
HTREEITEM hPrev = omTreeCtrl.GetPrevVisibleItem(hDroppingItem);
if(hPrev)
{
omTreeCtrl.EnsureVisible(hPrev);
}
HTREEITEM hNext = omTreeCtrl.GetNextVisibleItem(hDroppingItem);
if(hNext)
{
omTreeCtrl.EnsureVisible(hNext);
}
CPoint omCurPoint;
GetCursorPos(&omCurPoint);
ScreenToClient(&omCurPoint);
m_pomDragImageList->DragEnter(&omTreeCtrl, omCurPoint);
}
else if(eDroppingPos != NO_DROPPING && !IsItemCanDropOn(m_hDraggingItemgedItem, hDroppingItem))
{
eDroppingPos = NO_DROPPING;
}
return hDroppingItem;
}
HTREEITEM CTreeViewEx::DragMoveItem(HTREEITEM hDraggingItem, HTREEITEM hDroppingItem, eTYPE_DROPPING eDropping)
{
CTreeCtrl& omTreeCtrl = GetTreeCtrl();
if(eDropping == NO_DROPPING)
{
return NULL;
}
if(bAnscestor(hDraggingItem, hDroppingItem) || !IsItemCanDropOn(hDraggingItem, hDroppingItem))
{
return NULL;
}
if(bSuccessor(hDraggingItem, hDroppingItem) && (eDropping == DROPPING_ABOVE))
{
return NULL;
}
if(hDraggingItem == hDroppingItem)
{
return NULL;
}
if(!hDroppingItem && eDropping == DROPPING_BELOW)
for(hDroppingItem = omTreeCtrl.GetRootItem(); omTreeCtrl.GetNextSiblingItem(hDroppingItem) != 0; hDroppingItem = omTreeCtrl.GetNextSiblingItem(hDroppingItem));
// Setup insertion parameters
HTREEITEM hInsertAfter = 0;
HTREEITEM hParent = 0;
switch(eDropping)
{
case DROPPING_BELOW:
hInsertAfter = hDroppingItem;
hParent = omTreeCtrl.GetParentItem(hDroppingItem);
break;
case DROPPING_ABOVE:
hInsertAfter = omTreeCtrl.GetPrevSiblingItem(hDroppingItem);
if(!hInsertAfter)
{
hInsertAfter = TVI_FIRST;
}
hParent = omTreeCtrl.GetParentItem(hDroppingItem);
break;
default:
ASSERT(false);
break;
}
m_hDraggingItemgedItem = CopyTotalBranch(hDraggingItem, hParent, hInsertAfter);
omTreeCtrl.DeleteItem(hDraggingItem);
return hInsertAfter;
}
