public override void BeginSnap(GraphElement selectedElement) { if (IsActive) { throw new InvalidOperationException("SnapStrategy.BeginSnap: Snap to spacing already active. Call EndSnap() first."); } IsActive = true; m_GraphView = selectedElement.GraphView; if (m_LineView == null) { m_LineView = new LineView(m_GraphView); } m_GraphView.Add(m_LineView); }