void tree_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) != MouseButtons.Left)
{
return;
}
var tree = sender as TreeView;
if (tree == null)
{
return;
}
// The location here is always different than the one in tree_MouseDown.
// Sometimes, the difference is great enough to choose an adjacent item!
// See LT-10295. So we'll use the location stored in tree_MouseDown.
// (The sample code in MSDN uses the item/location information in MouseDown
// establish the item to drag in MouseMove.)
TreeNode selItem = tree.GetNodeAt(m_mouseDownLocation);
if (selItem == null)
{
return;
}
var item = new LocalDragItem(this, selItem);
tree.DoDragDrop(item, DragDropEffects.Move);
ClearDragHilite();
}
private bool OkToDrop(object sender, DragEventArgs e, out TreeNode destNode)
{
destNode = null;
// Don't allow drop in non-hierarchical lists.
if (m_list.OwningObject is CmPossibilityList && (m_list.OwningObject as CmPossibilityList).Depth < 2)
{
return(false);
}
TreeView tree = sender as TreeView;
if (tree == null)
{
return(false);
}
if (!e.Data.GetDataPresent(typeof(LocalDragItem)))
{
return(false);
}
destNode = tree.GetNodeAt(tree.PointToClient(new Point(e.X, e.Y)));
LocalDragItem item = (LocalDragItem)e.Data.GetData(typeof(LocalDragItem));
if (item.SourceNode == destNode)
{
return(false);
}
int hvoMove = (int)item.SourceNode.Tag;
int hvoDest = 0;
if (destNode != null)
{
hvoDest = (int)destNode.Tag;
}
// It must not be that hvoMove owns hvoDest
FdoCache cache = (FdoCache)m_mediator.PropertyTable.GetValue("cache");
for (int hvoOwner = hvoDest; hvoOwner != 0; hvoOwner = cache.GetOwnerOfObject(hvoOwner))
{
if (hvoOwner == hvoMove)
{
return(false);
}
}
return(true);
}
private bool OkToDrop(object sender, DragEventArgs e, out TreeNode destNode)
{
destNode = null;
// Don't allow drop in non-hierarchical lists.
if (m_list.OwningObject is ICmPossibilityList && (m_list.OwningObject as ICmPossibilityList).Depth < 2)
{
return(false);
}
TreeView tree = sender as TreeView;
if (tree == null)
{
return(false);
}
if (!e.Data.GetDataPresent(typeof(LocalDragItem)))
{
return(false);
}
destNode = tree.GetNodeAt(tree.PointToClient(new Point(e.X, e.Y)));
LocalDragItem item = (LocalDragItem)e.Data.GetData(typeof(LocalDragItem));
if (item.SourceNode == destNode)
{
return(false);
}
int hvoMove = (int)item.SourceNode.Tag;
int hvoDest = 0;
if (destNode != null)
{
hvoDest = (int)destNode.Tag;
}
if (hvoDest <= 0)
{
return(false);
}
// It must not be that hvoMove owns hvoDest
var destObj = m_objRepo.GetObject(hvoDest);
var moveObj = m_objRepo.GetObject(hvoMove);
return(!destObj.IsOwnedBy(moveObj));
}
/// <summary>
/// Currently we only know how to move our own items.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void tree_DragDrop(object sender, DragEventArgs e)
{
TreeNode destNode;
if (!OkToDrop(sender, e, out destNode))
{
return;
}
// Notification also gets sent to inactive handlers, which should ignore it.
LocalDragItem item = (LocalDragItem)e.Data.GetData(typeof(LocalDragItem));
if (item.Handler != this)
{
return;
}
if (e.Effect != DragDropEffects.Move)
{
return;
}
MoveItem(sender, destNode, item.SourceNode);
}
void tree_DragOver(object sender, DragEventArgs e)
{
if (!e.Data.GetDataPresent(typeof(LocalDragItem)))
{
e.Effect = DragDropEffects.None; // not my sort of data at all, can't drop
return;
}
// An inactive handler is unfortunately also being notified. Don't express any
// opinion at all about drag effects.
LocalDragItem item = (LocalDragItem)e.Data.GetData(typeof(LocalDragItem));
if (item.Handler != this)
{
return;
}
TreeNode destNode;
if (OkToDrop(sender, e, out destNode))
{
e.Effect = DragDropEffects.Move;
}
else
{
e.Effect = DragDropEffects.None;
}
if (destNode != m_dragHiliteNode)
{
ClearDragHilite();
m_dragHiliteNode = destNode;
if (m_dragHiliteNode != null)
{
m_dragHiliteNode.BackColor = Color.Gray;
}
}
}
void tree_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) != MouseButtons.Left)
return;
var tree = sender as TreeView;
if (tree == null)
return;
// The location here is always different than the one in tree_MouseDown.
// Sometimes, the difference is great enough to choose an adjacent item!
// See LT-10295. So we'll use the location stored in tree_MouseDown.
// (The sample code in MSDN uses the item/location information in MouseDown
// establish the item to drag in MouseMove.)
TreeNode selItem = tree.GetNodeAt(m_mouseDownLocation);
if (selItem == null)
return;
var item = new LocalDragItem(this, selItem);
tree.DoDragDrop(item, DragDropEffects.Move);
ClearDragHilite();
}