protected virtual void OnNodeExpanding(ExpandingEventArgs e)
{
if (this.NodeExpanding != null)
{
NodeExpanding(this, e);
}
}
internal protected virtual bool ExpandNode(TreeGridNode node)
{
if (!node.IsExpanded || this._virtualNodes)
{
ExpandingEventArgs exp = new ExpandingEventArgs(node);
this.OnNodeExpanding(exp);
if (!exp.Cancel)
{
this.LockVerticalScrollBarUpdate(true);
this.SuspendLayout();
_inExpandCollapse = true;
node.IsExpanded = true;
//TODO Convert this to a InsertRange
foreach (TreeGridNode childNode in node.Nodes)
{
Debug.Assert(childNode.RowIndex == -1, "Row is already in the grid.");
this.SiteNode(childNode);
}
ExpandedEventArgs exped = new ExpandedEventArgs(node);
this.OnNodeExpanded(exped);
//TODO: Convert this to a specific NodeCell property
_inExpandCollapse = false;
this.LockVerticalScrollBarUpdate(false);
this.ResumeLayout(true);
this.InvalidateCell(node.Cells[0]);
}
return(!exp.Cancel);
}
else
{
// row is already expanded, so we didn't do anything.
return(false);
}
}