gui-cs.Terminal.Gui/UICatalog/Scenarios/DynamicMenuBar.cs

using NStack;
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Text;
using Terminal.Gui;

namespace UICatalog {
	[ScenarioMetadata (Name: "Dynamic MenuBar", Description: "Demonstrates how to add and remove a MenuBar, Menus and change titles dynamically.")]
	[ScenarioCategory ("Dynamic")]
	class DynamicMenuBar : Scenario {
		public override void Run ()
		{
			Top.Add (new DynamicMenuBarSample (Win.Title));
			base.Run ();
		}
	}

	public class DynamicMenuItemList {
		public ustring Title { get; set; }
		public MenuItem MenuItem { get; set; }

		public DynamicMenuItemList () { }

		public DynamicMenuItemList (ustring title, MenuItem menuItem)
		{
			Title = title;
			MenuItem = menuItem;
		}

		public override string ToString () => $"{Title}, {MenuItem}";
	}

	public class DynamicMenuItem {
		public ustring title = "_New";
		public ustring help = "";
		public ustring action = "";
		public bool isTopLevel;
		public bool hasSubMenu;
		public MenuItemCheckStyle checkStyle;
		public ustring shortCut;

		public DynamicMenuItem () { }

		public DynamicMenuItem (ustring title, bool hasSubMenu = false)
		{
			this.title = title;
			this.hasSubMenu = hasSubMenu;
		}

		public DynamicMenuItem (ustring title, ustring help, ustring action, bool isTopLevel, bool hasSubMenu, MenuItemCheckStyle checkStyle = MenuItemCheckStyle.NoCheck, ustring shortCut = null)
		{
			this.title = title;
			this.help = help;
			this.action = action;
			this.isTopLevel = isTopLevel;
			this.hasSubMenu = hasSubMenu;
			this.checkStyle = checkStyle;
			this.shortCut = shortCut;
		}
	}

	public class DynamicMenuBarSample : Window {
		MenuBar _menuBar;
		MenuItem _currentMenuBarItem;
		int _currentSelectedMenuBar;
		MenuItem _currentEditMenuBarItem;
		ListView _lstMenus;

		public DynamicMenuItemModel DataContext { get; set; }

		public DynamicMenuBarSample (ustring title) : base (title)
		{
			DataContext = new DynamicMenuItemModel ();

			var _frmDelimiter = new FrameView ("ShortCut Delimiter:") {
				X = Pos.Center (),
				Y = 3,
				Width = 25,
				Height = 4
			};

			var _txtDelimiter = new TextField (MenuBar.ShortCutDelimiter.ToString ()) {
				X = Pos.Center(),
				Width = 2,
			};
			_txtDelimiter.TextChanged += (_) => MenuBar.ShortCutDelimiter = _txtDelimiter.Text;
			_frmDelimiter.Add (_txtDelimiter);

			Add (_frmDelimiter);

			var _frmMenu = new FrameView ("Menus:") {
				Y = 7,
				Width = Dim.Percent (50),
				Height = Dim.Fill ()
			};

			var _btnAddMenuBar = new Button ("Add a MenuBar") {
				Y = 1,
			};
			_frmMenu.Add (_btnAddMenuBar);

			var _btnMenuBarUp = new Button ("^") {
				X = Pos.Center ()
			};
			_frmMenu.Add (_btnMenuBarUp);

			var _btnMenuBarDown = new Button ("v") {
				X = Pos.Center (),
				Y = Pos.Bottom (_btnMenuBarUp)
			};
			_frmMenu.Add (_btnMenuBarDown);

			var _btnRemoveMenuBar = new Button ("Remove a MenuBar") {
				Y = 1
			};
			_btnRemoveMenuBar.X = Pos.AnchorEnd () - (Pos.Right (_btnRemoveMenuBar) - Pos.Left (_btnRemoveMenuBar));
			_frmMenu.Add (_btnRemoveMenuBar);

			var _btnPrevious = new Button ("<") {
				X = Pos.Left (_btnAddMenuBar),
				Y = Pos.Top (_btnAddMenuBar) + 2
			};
			_frmMenu.Add (_btnPrevious);

			var _btnAdd = new Button (" Add  ") {
				Y = Pos.Top (_btnPrevious) + 2,
			};
			_btnAdd.X = Pos.AnchorEnd () - (Pos.Right (_btnAdd) - Pos.Left (_btnAdd));
			_frmMenu.Add (_btnAdd);

			var _btnNext = new Button (">") {
				X = Pos.X (_btnAdd),
				Y = Pos.Top (_btnPrevious),
			};
			_frmMenu.Add (_btnNext);

			var _lblMenuBar = new Label () {
				ColorScheme = Colors.Dialog,
				TextAlignment = TextAlignment.Centered,
				X = Pos.Right (_btnPrevious) + 1,
				Y = Pos.Top (_btnPrevious),
				Width = Dim.Fill () - Dim.Width (_btnAdd) - 1,
				Height = 1
			};
			_frmMenu.Add (_lblMenuBar);
			_lblMenuBar.WantMousePositionReports = true;
			_lblMenuBar.CanFocus = true;

			var _lblParent = new Label () {
				TextAlignment = TextAlignment.Centered,
				X = Pos.Right (_btnPrevious) + 1,
				Y = Pos.Top (_btnPrevious) + 1,
				Width = Dim.Fill () - Dim.Width (_btnAdd) - 1
			};
			_frmMenu.Add (_lblParent);

			var _btnPreviowsParent = new Button ("..") {
				X = Pos.Left (_btnAddMenuBar),
				Y = Pos.Top (_btnPrevious) + 1
			};
			_frmMenu.Add (_btnPreviowsParent);

			_lstMenus = new ListView (new List<DynamicMenuItemList> ()) {
				ColorScheme = Colors.Dialog,
				X = Pos.Right (_btnPrevious) + 1,
				Y = Pos.Top (_btnPrevious) + 2,
				Width = _lblMenuBar.Width,
				Height = Dim.Fill (),
			};
			_frmMenu.Add (_lstMenus);

			_lblMenuBar.TabIndex = _btnPrevious.TabIndex + 1;
			_lstMenus.TabIndex = _lblMenuBar.TabIndex + 1;
			_btnNext.TabIndex = _lstMenus.TabIndex + 1;
			_btnAdd.TabIndex = _btnNext.TabIndex + 1;

			var _btnRemove = new Button ("Remove") {
				X = Pos.Left (_btnAdd),
				Y = Pos.Top (_btnAdd) + 1
			};
			_frmMenu.Add (_btnRemove);

			var _btnUp = new Button ("^") {
				X = Pos.Right (_lstMenus) + 2,
				Y = Pos.Top (_btnRemove) + 2
			};
			_frmMenu.Add (_btnUp);

			var _btnDown = new Button ("v") {
				X = Pos.Right (_lstMenus) + 2,
				Y = Pos.Top (_btnUp) + 1
			};
			_frmMenu.Add (_btnDown);

			Add (_frmMenu);


			var _frmMenuDetails = new DynamicMenuBarDetails ("Menu Details:") {
				X = Pos.Right (_frmMenu),
				Y = Pos.Top (_frmMenu),
				Width = Dim.Fill (),
				Height = Dim.Fill (2)
			};
			Add (_frmMenuDetails);

			_btnMenuBarUp.Clicked += () => {
				var i = _currentSelectedMenuBar;
				var menuItem = _menuBar != null && _menuBar.Menus.Length > 0 ? _menuBar.Menus [i] : null;
				if (menuItem != null) {
					var menus = _menuBar.Menus;
					if (i > 0) {
						menus [i] = menus [i - 1];
						menus [i - 1] = menuItem;
						_currentSelectedMenuBar = i - 1;
						_menuBar.SetNeedsDisplay ();
					}
				}
			};

			_btnMenuBarDown.Clicked += () => {
				var i = _currentSelectedMenuBar;
				var menuItem = _menuBar != null && _menuBar.Menus.Length > 0 ? _menuBar.Menus [i] : null;
				if (menuItem != null) {
					var menus = _menuBar.Menus;
					if (i < menus.Length - 1) {
						menus [i] = menus [i + 1];
						menus [i + 1] = menuItem;
						_currentSelectedMenuBar = i + 1;
						_menuBar.SetNeedsDisplay ();
					}
				}
			};

			_btnUp.Clicked += () => {
				var i = _lstMenus.SelectedItem;
				var menuItem = DataContext.Menus.Count > 0 ? DataContext.Menus [i].MenuItem : null;
				if (menuItem != null) {
					var childrens = ((MenuBarItem)_currentMenuBarItem).Children;
					if (i > 0) {
						childrens [i] = childrens [i - 1];
						childrens [i - 1] = menuItem;
						DataContext.Menus [i] = DataContext.Menus [i - 1];
						DataContext.Menus [i - 1] = new DynamicMenuItemList (menuItem.Title, menuItem);
						_lstMenus.SelectedItem = i - 1;
					}
				}
			};

			_btnDown.Clicked += () => {
				var i = _lstMenus.SelectedItem;
				var menuItem = DataContext.Menus.Count > 0 ? DataContext.Menus [i].MenuItem : null;
				if (menuItem != null) {
					var childrens = ((MenuBarItem)_currentMenuBarItem).Children;
					if (i < childrens.Length - 1) {
						childrens [i] = childrens [i + 1];
						childrens [i + 1] = menuItem;
						DataContext.Menus [i] = DataContext.Menus [i + 1];
						DataContext.Menus [i + 1] = new DynamicMenuItemList (menuItem.Title, menuItem);
						_lstMenus.SelectedItem = i + 1;
					}
				}
			};

			_btnPreviowsParent.Clicked += () => {
				if (_currentMenuBarItem != null && _currentMenuBarItem.Parent != null) {
					var mi = _currentMenuBarItem;
					_currentMenuBarItem = _currentMenuBarItem.Parent as MenuBarItem;
					SetListViewSource (_currentMenuBarItem, true);
					var i = ((MenuBarItem)_currentMenuBarItem).GetChildrenIndex (mi);
					if (i > -1) {
						_lstMenus.SelectedItem = i;
					}
					if (_currentMenuBarItem.Parent != null) {
						DataContext.Parent = _currentMenuBarItem.Title;
					} else {
						DataContext.Parent = ustring.Empty;
					}
				} else {
					DataContext.Parent = ustring.Empty;
				}
			};


			var _btnOk = new Button ("Ok") {
				X = Pos.Right (_frmMenu) + 20,
				Y = Pos.Bottom (_frmMenuDetails),
			};
			Add (_btnOk);

			var _btnCancel = new Button ("Cancel") {
				X = Pos.Right (_btnOk) + 3,
				Y = Pos.Top (_btnOk),
			};
			_btnCancel.Clicked += () => {
				SetFrameDetails (_currentEditMenuBarItem);
			};
			Add (_btnCancel);

			_lstMenus.SelectedItemChanged += (e) => {
				SetFrameDetails ();
			};

			_btnOk.Clicked += () => {
				if (ustring.IsNullOrEmpty (_frmMenuDetails._txtTitle.Text) && _currentEditMenuBarItem != null) {
					MessageBox.ErrorQuery ("Invalid title", "Must enter a valid title!.", "Ok");
				} else if (_currentEditMenuBarItem != null) {
					var menuItem = new DynamicMenuItem (_frmMenuDetails._txtTitle.Text, _frmMenuDetails._txtHelp.Text,
						_frmMenuDetails._txtAction.Text,
						_frmMenuDetails._ckbIsTopLevel != null ? _frmMenuDetails._ckbIsTopLevel.Checked : false,
						_frmMenuDetails._ckbSubMenu != null ? _frmMenuDetails._ckbSubMenu.Checked : false,
						_frmMenuDetails._rbChkStyle.SelectedItem == 0 ? MenuItemCheckStyle.NoCheck :
						_frmMenuDetails._rbChkStyle.SelectedItem == 1 ? MenuItemCheckStyle.Checked :
						MenuItemCheckStyle.Radio,
						_frmMenuDetails._txtShortCut.Text);
					UpdateMenuItem (_currentEditMenuBarItem, menuItem, _lstMenus.SelectedItem);
				}
			};

			_btnAdd.Clicked += () => {
				if (MenuBar == null) {
					MessageBox.ErrorQuery ("Menu Bar Error", "Must add a MenuBar first!", "Ok");
					_btnAddMenuBar.SetFocus ();
					return;
				}

				var frameDetails = new DynamicMenuBarDetails (null, _currentMenuBarItem != null);
				var item = frameDetails.EnterMenuItem ();
				if (item == null) {
					return;
				}

				if (!(_currentMenuBarItem is MenuBarItem)) {
					var parent = _currentMenuBarItem.Parent as MenuBarItem;
					var idx = parent.GetChildrenIndex (_currentMenuBarItem);
					_currentMenuBarItem = new MenuBarItem (_currentMenuBarItem.Title, new MenuItem [] { }, _currentMenuBarItem.Parent);
					_currentMenuBarItem.CheckType = item.checkStyle;
					parent.Children [idx] = _currentMenuBarItem;
				} else {
					MenuItem newMenu = CreateNewMenu (item, _currentMenuBarItem);
					var menuBarItem = _currentMenuBarItem as MenuBarItem;
					if (menuBarItem == null) {
						menuBarItem = new MenuBarItem (_currentMenuBarItem.Title, new MenuItem [] { newMenu }, _currentMenuBarItem.Parent);
					} else if (menuBarItem.Children == null) {
						menuBarItem.Children = new MenuItem [] { newMenu };
					} else {
						var childrens = menuBarItem.Children;
						Array.Resize (ref childrens, childrens.Length + 1);
						childrens [childrens.Length - 1] = newMenu;
						menuBarItem.Children = childrens;
					}
					DataContext.Menus.Add (new DynamicMenuItemList (newMenu.Title, newMenu));
					_lstMenus.MoveDown ();
				}
			};

			_btnRemove.Clicked += () => {
				var menuItem = DataContext.Menus.Count > 0 ? DataContext.Menus [_lstMenus.SelectedItem].MenuItem : null;
				if (menuItem != null) {
					var childrens = ((MenuBarItem)_currentMenuBarItem).Children;
					childrens [_lstMenus.SelectedItem] = null;
					int i = 0;
					foreach (var c in childrens) {
						if (c != null) {
							childrens [i] = c;
							i++;
						}
					}
					Array.Resize (ref childrens, childrens.Length - 1);
					if (childrens.Length == 0) {
						if (_currentMenuBarItem.Parent == null) {
							((MenuBarItem)_currentMenuBarItem).Children = null;
							//_currentMenuBarItem.Action = _frmMenuDetails.CreateAction (_currentEditMenuBarItem, new DynamicMenuItem (_currentMenuBarItem.Title));
						} else {
							_currentMenuBarItem = new MenuItem (_currentMenuBarItem.Title, _currentMenuBarItem.Help, _frmMenuDetails.CreateAction (_currentEditMenuBarItem, new DynamicMenuItem (_currentEditMenuBarItem.Title)), null, _currentMenuBarItem.Parent);
						}
					} else {
						((MenuBarItem)_currentMenuBarItem).Children = childrens;
					}
					DataContext.Menus.RemoveAt (_lstMenus.SelectedItem);
					if (_lstMenus.Source.Count > 0 && _lstMenus.SelectedItem > _lstMenus.Source.Count - 1) {
						_lstMenus.SelectedItem = _lstMenus.Source.Count - 1;
					}
					_lstMenus.SetNeedsDisplay ();
					SetFrameDetails ();
				}
			};

			_lstMenus.OpenSelectedItem += (e) => {
				_currentMenuBarItem = DataContext.Menus [e.Item].MenuItem;
				if (!(_currentMenuBarItem is MenuBarItem)) {
					MessageBox.ErrorQuery ("Menu Open Error", "Must allows sub menus first!", "Ok");
					return;
				}
				DataContext.Parent = _currentMenuBarItem.Title;
				DataContext.Menus = new List<DynamicMenuItemList> ();
				SetListViewSource (_currentMenuBarItem, true);
				var menuBarItem = DataContext.Menus.Count > 0 ? DataContext.Menus [0].MenuItem : null;
				SetFrameDetails (menuBarItem);
			};

			_lstMenus.Enter += (_) => {
				var menuBarItem = DataContext.Menus.Count > 0 ? DataContext.Menus [_lstMenus.SelectedItem].MenuItem : null;
				SetFrameDetails (menuBarItem);
			};

			_btnNext.Clicked += () => {
				if (_menuBar != null && _currentSelectedMenuBar + 1 < _menuBar.Menus.Length) {
					_currentSelectedMenuBar++;
				}
				SelectCurrentMenuBarItem ();
			};

			_btnPrevious.Clicked += () => {
				if (_currentSelectedMenuBar - 1 > -1) {
					_currentSelectedMenuBar--;
				}
				SelectCurrentMenuBarItem ();
			};

			_lblMenuBar.Enter += (e) => {
				if (_menuBar?.Menus != null) {
					_currentMenuBarItem = _menuBar.Menus [_currentSelectedMenuBar];
					SetFrameDetails (_menuBar.Menus [_currentSelectedMenuBar]);
				}
			};

			_btnAddMenuBar.Clicked += () => {
				var frameDetails = new DynamicMenuBarDetails (null, false);
				var item = frameDetails.EnterMenuItem ();
				if (item == null) {
					return;
				}

				if (MenuBar == null) {
					_menuBar = new MenuBar ();
					Add (_menuBar);
				}
				var newMenu = CreateNewMenu (item) as MenuBarItem;

				var menus = _menuBar.Menus;
				Array.Resize (ref menus, menus.Length + 1);
				menus [^1] = newMenu;
				_menuBar.Menus = menus;
				_currentMenuBarItem = newMenu;
				_currentMenuBarItem.CheckType = item.checkStyle;
				_currentSelectedMenuBar = menus.Length - 1;
				_menuBar.Menus [_currentSelectedMenuBar] = newMenu;
				_lblMenuBar.Text = newMenu.Title;
				SetListViewSource (_currentMenuBarItem, true);
				SetFrameDetails (_menuBar.Menus [_currentSelectedMenuBar]);
				_menuBar.SetNeedsDisplay ();
			};

			_btnRemoveMenuBar.Clicked += () => {
				if (_menuBar == null || _menuBar.Menus.Length == 0) {
					return;
				}

				if (_menuBar != null && _menuBar.Menus.Length > 0) {
					_menuBar.Menus [_currentSelectedMenuBar] = null;
					int i = 0;
					foreach (var m in _menuBar.Menus) {
						if (m != null) {
							_menuBar.Menus [i] = m;
							i++;
						}
					}
					var menus = _menuBar.Menus;
					Array.Resize (ref menus, menus.Length - 1);
					_menuBar.Menus = menus;
					if (_currentSelectedMenuBar - 1 >= 0 && _menuBar.Menus.Length > 0) {
						_currentSelectedMenuBar--;
					}
					_currentMenuBarItem = _menuBar.Menus?.Length > 0 ? _menuBar.Menus [_currentSelectedMenuBar] : null;
				}
				if (MenuBar != null && _currentMenuBarItem == null && _menuBar.Menus.Length == 0) {
					Remove (_menuBar);
					_menuBar = null;
					DataContext.Menus = new List<DynamicMenuItemList> ();
					_currentMenuBarItem = null;
					_currentSelectedMenuBar = -1;
					_lblMenuBar.Text = ustring.Empty;
				} else {
					_lblMenuBar.Text = _menuBar.Menus [_currentSelectedMenuBar].Title;
				}
				SetListViewSource (_currentMenuBarItem, true);
				SetFrameDetails (null);
			};


			SetFrameDetails ();


			var ustringConverter = new UStringValueConverter ();
			var listWrapperConverter = new ListWrapperConverter ();

			var lblMenuBar = new Binding (this, "MenuBar", _lblMenuBar, "Text", ustringConverter);
			var lblParent = new Binding (this, "Parent", _lblParent, "Text", ustringConverter);
			var lstMenus = new Binding (this, "Menus", _lstMenus, "Source", listWrapperConverter);


			void SetFrameDetails (MenuItem menuBarItem = null)
			{
				MenuItem menuItem;

				if (menuBarItem == null) {
					menuItem = DataContext.Menus.Count > 0 ? DataContext.Menus [_lstMenus.SelectedItem].MenuItem : null;
				} else {
					menuItem = menuBarItem;
				}

				_currentEditMenuBarItem = menuItem;
				_frmMenuDetails.EditMenuBarItem (menuItem);
				var f = _btnOk.CanFocus == _frmMenuDetails.CanFocus;
				if (!f) {
					_btnOk.CanFocus = _frmMenuDetails.CanFocus;
					_btnCancel.CanFocus = _frmMenuDetails.CanFocus;
				}
			}

			void SelectCurrentMenuBarItem ()
			{
				MenuBarItem menuBarItem = null;
				if (_menuBar?.Menus != null) {
					menuBarItem = _menuBar.Menus [_currentSelectedMenuBar];
					_lblMenuBar.Text = menuBarItem.Title;
				}
				SetFrameDetails (menuBarItem);
				_currentMenuBarItem = menuBarItem;
				DataContext.Menus = new List<DynamicMenuItemList> ();
				SetListViewSource (_currentMenuBarItem, true);
				_lblParent.Text = ustring.Empty;
			}

			void SetListViewSource (MenuItem _currentMenuBarItem, bool fill = false)
			{
				DataContext.Menus = new List<DynamicMenuItemList> ();
				var menuBarItem = _currentMenuBarItem as MenuBarItem;
				if (menuBarItem != null && menuBarItem?.Children == null) {
					return;
				}
				if (!fill) {
					return;
				}
				if (menuBarItem != null) {
					foreach (var child in menuBarItem?.Children) {
						var m = new DynamicMenuItemList (child.Title, child);
						DataContext.Menus.Add (m);
					}
				}
			}

			MenuItem CreateNewMenu (DynamicMenuItem item, MenuItem parent = null)
			{
				MenuItem newMenu;
				if (item.hasSubMenu) {
					newMenu = new MenuBarItem (item.title, new MenuItem [] { }, parent);
				} else if (parent != null) {
					newMenu = new MenuItem (item.title, item.help, null, null, parent);
					newMenu.CheckType = item.checkStyle;
					newMenu.Action = _frmMenuDetails.CreateAction (newMenu, item);
					newMenu.ShortCut = ShortCutHelper.GetShortCutFromTag (item.shortCut);
				} else if (item.isTopLevel) {
					newMenu = new MenuBarItem (item.title, item.help, null);
					newMenu.Action = _frmMenuDetails.CreateAction (newMenu, item);
				} else {
					newMenu = new MenuBarItem (item.title, item.help, null);
					((MenuBarItem)newMenu).Children [0].Action = _frmMenuDetails.CreateAction (newMenu, item);
					((MenuBarItem)newMenu).Children [0].ShortCut = ShortCutHelper.GetShortCutFromTag (item.shortCut);
				}

				return newMenu;
			}

			void UpdateMenuItem (MenuItem _currentEditMenuBarItem, DynamicMenuItem menuItem, int index)
			{
				_currentEditMenuBarItem.Title = menuItem.title;
				_currentEditMenuBarItem.Help = menuItem.help;
				_currentEditMenuBarItem.CheckType = menuItem.checkStyle;
				var parent = _currentEditMenuBarItem.Parent as MenuBarItem;
				if (parent != null && parent.Children.Length == 1 && _currentEditMenuBarItem.CheckType == MenuItemCheckStyle.Radio) {
					_currentEditMenuBarItem.Checked = true;
				}
				if (menuItem.isTopLevel && _currentEditMenuBarItem is MenuBarItem) {
					((MenuBarItem)_currentEditMenuBarItem).Children = null;
					_currentEditMenuBarItem.Action = _frmMenuDetails.CreateAction (_currentEditMenuBarItem, menuItem);
					SetListViewSource (_currentEditMenuBarItem, true);
				} else if (menuItem.hasSubMenu) {
					_currentEditMenuBarItem.Action = null;
					if (_currentEditMenuBarItem is MenuBarItem && ((MenuBarItem)_currentEditMenuBarItem).Children == null) {
						((MenuBarItem)_currentEditMenuBarItem).Children = new MenuItem [] { };
					} else if (_currentEditMenuBarItem.Parent != null) {
						_frmMenuDetails.UpdateParent (ref _currentEditMenuBarItem);
					} else {
						_currentEditMenuBarItem = new MenuBarItem (_currentEditMenuBarItem.Title, new MenuItem [] { }, _currentEditMenuBarItem.Parent);
					}
					SetListViewSource (_currentEditMenuBarItem, true);
				} else if (_currentEditMenuBarItem is MenuBarItem && _currentEditMenuBarItem.Parent != null) {
					_frmMenuDetails.UpdateParent (ref _currentEditMenuBarItem);
					_currentEditMenuBarItem = new MenuItem (menuItem.title, menuItem.help, _frmMenuDetails.CreateAction (_currentEditMenuBarItem, menuItem), null, _currentEditMenuBarItem.Parent);
				} else {
					if (_currentEditMenuBarItem is MenuBarItem) {
						((MenuBarItem)_currentEditMenuBarItem).Children = null;
						DataContext.Menus = new List<DynamicMenuItemList> ();
					}
					_currentEditMenuBarItem.Action = _frmMenuDetails.CreateAction (_currentEditMenuBarItem, menuItem);
					_currentEditMenuBarItem.ShortCut = ShortCutHelper.GetShortCutFromTag (menuItem.shortCut);
				}

				if (_currentEditMenuBarItem.Parent == null) {
					DataContext.MenuBar = _currentEditMenuBarItem.Title;
				} else {
					if (DataContext.Menus.Count == 0) {
						DataContext.Menus.Add (new DynamicMenuItemList (_currentEditMenuBarItem.Title, _currentEditMenuBarItem));
					}
					DataContext.Menus [index] = new DynamicMenuItemList (_currentEditMenuBarItem.Title, _currentEditMenuBarItem);
				}
				_currentEditMenuBarItem.CheckType = menuItem.checkStyle;
				SetFrameDetails (_currentEditMenuBarItem);
			}


			_frmMenuDetails.Initialized += (s, e) => _frmMenuDetails.CanFocus = false;
		}
	}

	public class DynamicMenuBarDetails : FrameView {
		public MenuItem _menuItem;
		public TextField _txtTitle;
		public TextField _txtHelp;
		public TextView _txtAction;
		public CheckBox _ckbIsTopLevel;
		public CheckBox _ckbSubMenu;
		public RadioGroup _rbChkStyle;
		public TextField _txtShortCut;

		bool hasParent;

		public DynamicMenuBarDetails (MenuItem menuItem = null, bool hasParent = false) : this (menuItem == null ? "Adding New Menu." : "Editing Menu.")
		{
			_menuItem = menuItem;
			this.hasParent = hasParent;
		}

		public DynamicMenuBarDetails (ustring title) : base (title)
		{
			var _lblTitle = new Label ("Title:") {
				Y = 1
			};
			Add (_lblTitle);

			_txtTitle = new TextField () {
				X = Pos.Right (_lblTitle) + 2,
				Y = Pos.Top (_lblTitle),
				Width = Dim.Fill ()
			};
			Add (_txtTitle);

			var _lblHelp = new Label ("Help:") {
				X = Pos.Left (_lblTitle),
				Y = Pos.Bottom (_lblTitle) + 1
			};
			Add (_lblHelp);

			_txtHelp = new TextField () {
				X = Pos.Left (_txtTitle),
				Y = Pos.Top (_lblHelp),
				Width = Dim.Fill ()
			};
			Add (_txtHelp);

			var _lblAction = new Label ("Action:") {
				X = Pos.Left (_lblTitle),
				Y = Pos.Bottom (_lblHelp) + 1
			};
			Add (_lblAction);

			_txtAction = new TextView () {
				ColorScheme = Colors.Dialog,
				X = Pos.Left (_txtTitle),
				Y = Pos.Top (_lblAction),
				Width = Dim.Fill (),
				Height = 5
			};
			Add (_txtAction);

			_ckbIsTopLevel = new CheckBox ("IsTopLevel") {
				X = Pos.Left (_lblTitle),
				Y = Pos.Bottom (_lblAction) + 5
			};
			Add (_ckbIsTopLevel);

			_ckbSubMenu = new CheckBox ("Has sub-menus") {
				X = Pos.Left (_lblTitle),
				Y = Pos.Bottom (_ckbIsTopLevel),
				Checked = _menuItem == null ? !hasParent : HasSubMenus (_menuItem)
			};
			Add (_ckbSubMenu);

			var _rChkLabels = new ustring [] { "NoCheck", "Checked", "Radio" };
			_rbChkStyle = new RadioGroup (_rChkLabels) {
				X = Pos.Left (_lblTitle),
				Y = Pos.Bottom (_ckbSubMenu) + 1,
			};
			Add (_rbChkStyle);

			var _lblShortCut = new Label ("ShortCut:") {
				X = Pos.Right (_ckbSubMenu) + 10,
				Y = Pos.Top (_ckbSubMenu)
			};
			Add (_lblShortCut);

			_txtShortCut = new TextField () {
				X = Pos.X (_lblShortCut),
				Y = Pos.Bottom (_lblShortCut),
				Width = Dim.Fill (),
				ReadOnly = true
			};
			_txtShortCut.KeyDown += (e) => {
				if (!ProcessKey (e.KeyEvent)) {
					return;
				}

				var k = GetModifiersKey (e.KeyEvent);
				if (CheckShortCut (k, true)) {
					e.Handled = true;
				}
			};

			bool ProcessKey (KeyEvent ev)
			{
				switch (ev.Key) {
				case Key.CursorUp:
				case Key.CursorDown:
				case Key.Tab:
				case Key.BackTab:
					return false;
				}

				return true;
			}

			bool CheckShortCut (Key k, bool pre)
			{
				var m = _menuItem != null ? _menuItem : new MenuItem ();
				if (pre && !ShortCutHelper.PreShortCutValidation (k)) {
					_txtShortCut.Text = "";
					return false;
				}
				if (!pre) {
					if (!ShortCutHelper.PostShortCutValidation (ShortCutHelper.GetShortCutFromTag (_txtShortCut.Text))) {
						_txtShortCut.Text = "";
						return false;
					}
					return true;
				}
				_txtShortCut.Text = ShortCutHelper.GetShortCutTag (k);

				return true;
			}

			_txtShortCut.KeyUp += (e) => {
				var k = GetModifiersKey (e.KeyEvent);
				if (CheckShortCut (k, false)) {
					e.Handled = true;
				}
			};
			Add (_txtShortCut);

			var _btnShortCut = new Button ("Clear ShortCut") {
				X = Pos.X (_lblShortCut),
				Y = Pos.Bottom (_txtShortCut) + 1
			};
			_btnShortCut.Clicked += () => {
				_txtShortCut.Text = "";
			};
			Add (_btnShortCut);

			_ckbIsTopLevel.Toggled += (e) => {
				if ((_menuItem != null && _menuItem.Parent != null && _ckbIsTopLevel.Checked) ||
					_menuItem == null && hasParent && _ckbIsTopLevel.Checked) {
					MessageBox.ErrorQuery ("Invalid IsTopLevel", "Only menu bar can have top level menu item!", "Ok");
					_ckbIsTopLevel.Checked = false;
					return;
				}
				if (_ckbIsTopLevel.Checked) {
					_ckbSubMenu.Checked = false;
					_ckbSubMenu.SetNeedsDisplay ();
					_txtHelp.CanFocus = true;
					_txtAction.CanFocus = true;
					_txtShortCut.CanFocus = !_ckbIsTopLevel.Checked && !_ckbSubMenu.Checked;
				} else {
					if (_menuItem == null && !hasParent || _menuItem.Parent == null) {
						_ckbSubMenu.Checked = true;
						_ckbSubMenu.SetNeedsDisplay ();
						_txtShortCut.CanFocus = false;
					}
					_txtHelp.Text = "";
					_txtHelp.CanFocus = false;
					_txtAction.Text = "";
					_txtAction.CanFocus = false;
				}
			};
			_ckbSubMenu.Toggled += (e) => {
				if (_ckbSubMenu.Checked) {
					_ckbIsTopLevel.Checked = false;
					_ckbIsTopLevel.SetNeedsDisplay ();
					_txtHelp.Text = "";
					_txtHelp.CanFocus = false;
					_txtAction.Text = "";
					_txtAction.CanFocus = false;
					_txtShortCut.Text = "";
					_txtShortCut.CanFocus = false;
				} else {
					if (!hasParent) {
						_ckbIsTopLevel.Checked = true;
						_ckbIsTopLevel.SetNeedsDisplay ();
						_txtShortCut.CanFocus = false;
					}
					_txtHelp.CanFocus = true;
					_txtAction.CanFocus = true;
					_txtShortCut.CanFocus = !_ckbIsTopLevel.Checked && !_ckbSubMenu.Checked;
				}
			};

			//Add (_frmMenuDetails);

		}


		public DynamicMenuItem EnterMenuItem ()
		{
			var valid = false;

			if (_menuItem == null) {
				var m = new DynamicMenuItem ();
				_txtTitle.Text = m.title;
				_txtHelp.Text = m.help;
				_txtAction.Text = m.action;
				_ckbIsTopLevel.Checked = false;
				_ckbSubMenu.Checked = !hasParent;
				_txtHelp.CanFocus = hasParent;
				_txtAction.CanFocus = hasParent;
				_txtShortCut.CanFocus = hasParent;
			} else {
				EditMenuBarItem (_menuItem);
			}

			var _btnOk = new Button ("Ok") {
				IsDefault = true,
			};
			_btnOk.Clicked += () => {
				if (ustring.IsNullOrEmpty (_txtTitle.Text)) {
					MessageBox.ErrorQuery ("Invalid title", "Must enter a valid title!.", "Ok");
				} else {
					valid = true;
					Application.RequestStop ();
				}
			};
			var _btnCancel = new Button ("Cancel");
			_btnCancel.Clicked += () => {
				_txtTitle.Text = ustring.Empty;
				Application.RequestStop ();
			};
			var _dialog = new Dialog ("Please enter the menu details.", _btnOk, _btnCancel);

			Width = Dim.Fill ();
			Height = Dim.Fill () - 1;
			_dialog.Add (this);
			_txtTitle.SetFocus ();
			_txtTitle.CursorPosition = _txtTitle.Text.Length;
			Application.Run (_dialog);

			if (valid) {
				return new DynamicMenuItem (_txtTitle.Text, _txtHelp.Text, _txtAction.Text,
					_ckbIsTopLevel != null ? _ckbIsTopLevel.Checked : false,
					_ckbSubMenu != null ? _ckbSubMenu.Checked : false,
					_rbChkStyle.SelectedItem == 0 ? MenuItemCheckStyle.NoCheck :
					_rbChkStyle.SelectedItem == 1 ? MenuItemCheckStyle.Checked : MenuItemCheckStyle.Radio,
					_txtShortCut.Text);
			} else {
				return null;
			}
		}

		public void EditMenuBarItem (MenuItem menuItem)
		{
			if (menuItem == null) {
				hasParent = false;
				CanFocus = false;
				CleanEditMenuBarItem ();
				return;
			} else {
				hasParent = menuItem.Parent != null;
				CanFocus = true;
			}
			_menuItem = menuItem;
			_txtTitle.Text = menuItem?.Title ?? "";
			_txtHelp.Text = menuItem?.Help ?? "";
			_txtAction.Text = menuItem != null && menuItem.Action != null ? GetTargetAction (menuItem.Action) : ustring.Empty;
			_ckbIsTopLevel.Checked = IsTopLevel (menuItem);
			_ckbSubMenu.Checked = HasSubMenus (menuItem);
			_txtHelp.CanFocus = !_ckbSubMenu.Checked;
			_txtAction.CanFocus = !_ckbSubMenu.Checked;
			_rbChkStyle.SelectedItem = (int)(menuItem?.CheckType ?? MenuItemCheckStyle.NoCheck);
			_txtShortCut.Text = menuItem?.ShortCutTag ?? "";
			_txtShortCut.CanFocus = !_ckbIsTopLevel.Checked && !_ckbSubMenu.Checked;
		}

		void CleanEditMenuBarItem ()
		{
			_txtTitle.Text = "";
			_txtHelp.Text = "";
			_txtAction.Text = "";
			_ckbIsTopLevel.Checked = false;
			_ckbSubMenu.Checked = false;
			_rbChkStyle.SelectedItem = (int)MenuItemCheckStyle.NoCheck;
			_txtShortCut.Text = "";
		}

		ustring GetTargetAction (Action action)
		{
			var me = action.Target;

			if (me == null) {
				throw new ArgumentException ();
			}
			object v = new object ();
			foreach (var field in me.GetType ().GetFields ()) {
				if (field.Name == "item") {
					v = field.GetValue (me);
				}
			}
			return v == null || !(v is DynamicMenuItem item) ? ustring.Empty : item.action;
		}

		bool IsTopLevel (MenuItem menuItem)
		{
			var topLevel = menuItem as MenuBarItem;
			if (topLevel != null && topLevel.Parent == null && (topLevel.Children == null || topLevel.Children.Length == 0) && topLevel.Action != null) {
				return true;
			} else {
				return false;
			}
		}

		bool HasSubMenus (MenuItem menuItem)
		{
			var menuBarItem = menuItem as MenuBarItem;
			if (menuBarItem != null && menuBarItem.Children != null && (menuBarItem.Children.Length > 0 || menuBarItem.Action == null)) {
				return true;
			} else {
				return false;
			}
		}

		public Action CreateAction (MenuItem menuItem, DynamicMenuItem item)
		{
			switch (menuItem.CheckType) {
			case MenuItemCheckStyle.NoCheck:
				return new Action (() => MessageBox.ErrorQuery (item.title, item.action, "Ok"));
			case MenuItemCheckStyle.Checked:
				return new Action (() => menuItem.Checked = !menuItem.Checked);
			case MenuItemCheckStyle.Radio:
				break;
			}
			return new Action (() => {
				menuItem.Checked = true;
				var parent = menuItem?.Parent as MenuBarItem;
				if (parent != null) {
					var childrens = parent.Children;
					for (int i = 0; i < childrens.Length; i++) {
						var child = childrens [i];
						if (child != menuItem) {
							child.Checked = false;
						}
					}
				}
			});
		}

		public void UpdateParent (ref MenuItem menuItem)
		{
			var parent = menuItem.Parent as MenuBarItem;
			var idx = parent.GetChildrenIndex (menuItem);
			if (!(menuItem is MenuBarItem)) {
				menuItem = new MenuBarItem (menuItem.Title, new MenuItem [] { }, menuItem.Parent);
				if (idx > -1) {
					parent.Children [idx] = menuItem;
				}
			} else {
				menuItem = new MenuItem (menuItem.Title, menuItem.Help, CreateAction (menuItem, new DynamicMenuItem ()), null, menuItem.Parent);
				if (idx > -1) {
					parent.Children [idx] = menuItem;
				}
			}
		}
	}

	public class DynamicMenuItemModel : INotifyPropertyChanged {
		public event PropertyChangedEventHandler PropertyChanged;

		private ustring menuBar;
		private ustring parent;
		private List<DynamicMenuItemList> menus;

		public ustring MenuBar {
			get => menuBar;
			set {
				if (value != menuBar) {
					menuBar = value;
					PropertyChanged?.Invoke (this, new PropertyChangedEventArgs (GetPropertyName ()));
				}
			}
		}

		public ustring Parent {
			get => parent;
			set {
				if (value != parent) {
					parent = value;
					PropertyChanged?.Invoke (this, new PropertyChangedEventArgs (GetPropertyName ()));
				}
			}
		}

		public List<DynamicMenuItemList> Menus {
			get => menus;
			set {
				if (value != menus) {
					menus = value;
					PropertyChanged?.Invoke (this, new PropertyChangedEventArgs (GetPropertyName ()));
				}
			}
		}

		public DynamicMenuItemModel ()
		{
			Menus = new List<DynamicMenuItemList> ();
		}

		public string GetPropertyName ([CallerMemberName] string propertyName = null)
		{
			return propertyName;
		}
	}

	public interface IValueConverter {
		object Convert (object value, object parameter = null);
	}

	public class Binding {
		public View Target { get; private set; }
		public View Source { get; private set; }

		public string SourcePropertyName { get; private set; }
		public string TargetPropertyName { get; private set; }

		private object sourceDataContext;
		private PropertyInfo sourceBindingProperty;
		private IValueConverter valueConverter;

		public Binding (View source, string sourcePropertyName, View target, string targetPropertyName, IValueConverter valueConverter = null)
		{
			Target = target;
			Source = source;
			SourcePropertyName = sourcePropertyName;
			TargetPropertyName = targetPropertyName;
			sourceDataContext = Source.GetType ().GetProperty ("DataContext").GetValue (Source);
			sourceBindingProperty = sourceDataContext.GetType ().GetProperty (SourcePropertyName);
			this.valueConverter = valueConverter;
			UpdateTarget ();

			var notifier = ((INotifyPropertyChanged)sourceDataContext);
			if (notifier != null) {
				notifier.PropertyChanged += (s, e) => {
					if (e.PropertyName == SourcePropertyName) {
						UpdateTarget ();
					}
				};
			}
		}

		private void UpdateTarget ()
		{
			try {
				var sourceValue = sourceBindingProperty.GetValue (sourceDataContext);
				if (sourceValue == null) {
					return;
				}

				var finalValue = valueConverter?.Convert (sourceValue) ?? sourceValue;

				var targetProperty = Target.GetType ().GetProperty (TargetPropertyName);
				targetProperty.SetValue (Target, finalValue);
			} catch (Exception ex) {
				MessageBox.ErrorQuery ("Binding Error", $"Binding failed: {ex}.", "Ok");
			}
		}
	}

	public class ListWrapperConverter : IValueConverter {
		public object Convert (object value, object parameter = null)
		{
			return new ListWrapper ((IList)value);
		}
	}

	public class UStringValueConverter : IValueConverter {
		public object Convert (object value, object parameter = null)
		{
			var data = Encoding.ASCII.GetBytes (value.ToString ());
			return ustring.Make (data);
		}
	}
}