UnityEditor.AudioMixerGroupSelector.OnGUI C# (CSharp) Method

        public override void OnGUI(Rect rect)
        {
            if (this.m_TreeView == null)
            {
                this.InitTreeView(rect);
            }
            Rect treeViewRect = new Rect(rect.x, 0f, rect.width, rect.height);
            this.HandleKeyboard();
            this.TreeViewArea(treeViewRect);
            if ((Event.current.type == EventType.KeyDown) && (Event.current.keyCode == KeyCode.Escape))
            {
                this.Cancel();
            }
        }