internal void ChangeLayer(GraphElement element) { if (!m_ContainerLayers.ContainsKey(element.layer)) { AddLayer(element.layer); } bool selected = element.selected; if (selected) { element.UnregisterCallback <DetachFromPanelEvent>(OnSelectedElementDetachedFromPanel); } GetLayer(element.layer).Add(element); if (selected) { element.RegisterCallback <DetachFromPanelEvent>(OnSelectedElementDetachedFromPanel); } }