private void TreeControl_NodeExpandedChanging(object sender, TreeControl.CancelNodeEventArgs e)
{
var treeView = TreeView.As <FilteredTreeView>();
// early exit
if (m_updating || !m_searching || e.Node.Tag == null ||
treeView == null)
{
return;
}
// is the node or any of its decendants passed filter
if (treeView.IsMatched(e.Node.Tag))
{
if (e.Node.Expanded)
{
if (!treeView.IsFullyExpaned(e.Node.Tag))
{
// add all the children that did not pass
// the filtering to the exempted set.
treeView.AddToExemptSet(e.Node.Tag);
// save e.Node and expand it in NodeExpandedChanged event handler.
m_toExpand = e.Node;
}
if (RestoreSubExpansion)
{
treeView.SaveExpansion(e.Node);
}
} // end of if (e.Node.Expanded )
else
{ // e.Node about to expand. Remove all its children from exempted set.
// so normal filtering will be applied.
treeView.RemoveFromExemptSet(e.Node.Tag);
}
}// end of if(treeView.IsMatched(e.Node.Tag))
else
{
if (e.Node.Expanded)
{
if (RestoreSubExpansion)
{
treeView.SaveExpansion(e.Node);
}
}
else
{
treeView.AddToExemptSet(e.Node.Tag);
}
}
}
/// <summary>
/// Performs custom actions before changing a node's Expanded property</summary>
/// <param name="sender">Sender</param>
/// <param name="e">Event args</param>
void treeControl_NodeExpandedChanging(object sender, TreeControl.CancelNodeEventArgs e)
{
if ((!m_autoExpanding) && m_searching)
{
var filteredTreeView = TreeView as FilteredTreeView;
// 3 states to toggle:
if (filteredTreeView.IsNodeOpaque(e.Node) && filteredTreeView.IsNodeCurrentlyOpaque(e.Node))
{
// two cases here: a) if the node is expanding and all the child nodes are opaque, just expand all its children
// if some of the child nodes are visible, and the node is already expanded, then we need to expand all its children too
IEnumerable <object> itsChildren = filteredTreeView.GetChildren(e.Node.Tag); // get visible children
if (!itsChildren.Any())
{
if (!e.Node.Expanded) /* case a*/
{
foreach (object child in filteredTreeView.GetUnfilteredChildren(e.Node.Tag))
{
filteredTreeView.AddCurrentVisibleNode(child);
}
}
}
else if (e.Node.Expanded) // an opaque node is about to collapsing; but we actually want it fully expanded
{
// this is a manual click-expanding case, make all children of the node visible
bool added = false;
foreach (object child in filteredTreeView.GetUnfilteredChildren(e.Node.Tag))
{
if (filteredTreeView.AddCurrentVisibleNode(child))
{
added = true;
}
}
filteredTreeView.RemoveOpaqueNode(e.Node);
filteredTreeView.RememberExpansion(e.Node);
if (added) // if false, all children are already visible, just collapse the node
{
m_nodeToExpand = e.Node;
}
}
}
else if (filteredTreeView.IsNodeOpaque(e.Node) && (!filteredTreeView.IsNodeCurrentlyOpaque(e.Node)) && (e.Node.Expanded))
{
// the opaque node is fakely(fully) expanded, restore to hide non-matched ones
filteredTreeView.AddOpaqueNode(e.Node);
filteredTreeView.RememberExpansion(e.Node);
foreach (TreeControl.Node child in e.Node.Children)
{
if (!filteredTreeView.IsNodeMatched(child))
{
filteredTreeView.RemoveVisibleNode(child.Tag);
}
}
}
else if (e.Node.Expanded)
{
filteredTreeView.RememberExpansion(e.Node);
}
else if (!filteredTreeView.IsNodeOpaque(e.Node)) // check expanding a node with all childen invisible
{
foreach (object child in filteredTreeView.GetUnfilteredChildren(e.Node.Tag))
{
filteredTreeView.AddCurrentVisibleNode(child);
}
}
}
}
