/** * @brief set the menu according to current m_selectedNode **/ private void UpdateMenu() { if (m_selectedNode != null) { if (m_selectedNode.CanAddMoreChild()) { menuInsert.Enabled = true; } else { menuInsert.Enabled = false; } if (m_selectedNode != btTreeViewer.BTTree.Root) { // cannot remove root menuRemoveNode.Enabled = true; } else { menuRemoveNode.Enabled = false; } } else { menuInsert.Enabled = false; menuRemoveNode.Enabled = false; } }