void _removeSymbol(string symbol)
 {
     m_scriptingDefineSymbols.Remove(symbol);
     PlayerSettingsUtils.SetScriptingDefineSymbols(m_scriptingDefineSymbols);
     AssetDatabase.Refresh();
     RegisterFiles();
 }
        public TreeView_ActiveSymbols() : base(new TreeViewState())
        {
            E.Load();
            m_scriptingDefineSymbols = PlayerSettingsUtils.GetScriptingDefineSymbolsAtList();

            showAlternatingRowBackgrounds = true;
            rowHeight = EditorGUIUtility.singleLineHeight;
            var lst = new List <MultiColumnHeaderState.Column>();

            lst.Add(new MultiColumnHeaderState.Column()
            {
                headerContent = GUIContent.none,
                width         = 24,
                maxWidth      = 24,
                minWidth      = 24,
            });
            lst.Add(new MultiColumnHeaderState.Column()
            {
                headerContent = new GUIContent(S._SymbolName),
            });

            multiColumnHeader = new MultiColumnHeader(new MultiColumnHeaderState(lst.ToArray()));
            multiColumnHeader.ResizeToFit();
            multiColumnHeader.height = 22;
            //multiColumnHeader.sortingChanged += OnSortingChanged;

            RegisterFiles();
        }