MainMenuView.cs

using System;
using Cirrious.MvvmCross.Binding.BindingContext;
using Cirrious.MvvmCross.Binding.Touch.Views;
using UIKit;
using Foundation;
using DirecTV.iPad.Utils;
using Cirrious.MvvmCross.ViewModels;
using CoreGraphics;
using DirecTV.Core.Models;
using System.Collections.ObjectModel;
using DirecTV.iPad.Common.Views;
using DirecTV.Core.Apps.LiveService.ViewModels;
using DirecTV.iPad.Apps.LiveService.Views.Cells;
using System.Collections.Generic;
using Cirrious.CrossCore;

namespace DirecTV.iPad.Apps.LiveService.Views.Menus
{
	public partial class MainMenuView : MvxView, IDestroyable
	{
		static NSString headerId = new NSString ("CollectionHeader");

		public BaseMenuView BaseView;

		private MvxImageViewLoader _imageLoader;
		private TableSource _tableSource;

		private CollectionSource _collectionSource;
		private MvxPropertyChangedListener _listener;

		public MainMenuViewModel VM {
			get { return DataContext as MainMenuViewModel; }
		}

		public MainMenuView () : base ()
		{
			InitBindings();
			CreateBaseView();
			StyleHelper.MenuView(this);
		}

		public MainMenuView (IntPtr handle) : base (handle)
		{
			InitBindings ();
		}

		void CreateBaseView ()
		{
			BaseView = BaseMenuView.Create ();
			BaseView.Frame = new CoreGraphics.CGRect (0, 0, Bounds.Width, Bounds.Height);
		    BaseView.BackgroundColor = UIColor.Clear;
			Add (BaseView);
		}

		void InitBindings ()
		{
			this.DelayBind (() => {

				_imageLoader = new MvxImageViewLoader (() => this.BaseView.StaticImageView) { };

				var set = this.CreateBindingSet<MainMenuView, MainMenuViewModel> ();
				set.Bind (_collectionSource).To (vm => vm.SubMenuItems);
				set.Bind (_collectionSource).For (s => s.SelectionChangedCommand).To (vm => vm.SubMenuItemSelectedCommand);
				set.Bind (_imageLoader).To (vm => vm.SubMenuStaticImage);
				set.Apply ();

				_listener = new MvxPropertyChangedListener (VM);
				_listener.Listen (() => VM.SelectedTableViewMenuItem, OnTableViewChange);
				_listener.Listen (() => VM.SelectedCollectionViewMenuItemIndex, OnCollectionViewChange);

				_listener.Listen (() => VM.SubMenuItems, () => {
					if (VM.SubMenuItems.Count > 0) {
						SetupSubMenuItemCollectionView ();
					}
				});

				_listener.Listen (() => VM.ProgramSections, () => {
					if (VM.ProgramSections.Count > 0) {
						SetupProgramsCollectionView ();
					}
				});

				SetupProgramsCollectionView ();
				SetupTable ();

			});
		}

		void SetupTable ()
		{
			_tableSource = new TableSource (BaseView.MenuTableView) {
				UseAnimations = false
			};

			this.AddBindings (new Dictionary<object, string> {
				{ _tableSource, "ItemsSource MenuItems; SelectionChangedCommand SelectedCommand" }
			});

			BaseView.MenuTableView.Source = _tableSource;
			BaseView.MenuTableView.ReloadData ();
			OnTableViewChange ();
		}

		private void OnTableViewChange ()
		{
			// set the selection
			_tableSource.TableView.SelectRow (NSIndexPath.FromRowSection (VM.SelectedTableViewMenuItem, 0), false, UITableViewScrollPosition.None);            

			// trigger the change of the collectionview
//			VM.SelectedCommand.Execute();
			_tableSource.RowSelected(_tableSource.TableView, NSIndexPath.FromRowSection (VM.SelectedTableViewMenuItem, 0));
		}

		private void OnCollectionViewChange ()
		{
			_collectionSource.CollectionView.SelectItem(NSIndexPath.FromRowSection (VM.SelectedCollectionViewMenuItemIndex, VM.SelectedCollectionViewMenuItemSection), false, UICollectionViewScrollPosition.None);

			if(VM.SubMenuItems != null && VM.SubMenuItems.Count > 0) {
				if (VM.SelectedCollectionViewMenuItemIndex < 0) {
					VM.SubMenuItems [VM.ActiveSubMenuItem].Selected = false;
					return;
				}
				VM.CollectionViewMenuItemCommand.Execute (VM.SubMenuItems [VM.SelectedCollectionViewMenuItemIndex]);
			} else {
				VM.ProgramsItemCommand.Execute (VM.ProgramSections [VM.SelectedCollectionViewMenuItemSection].Programs[VM.SelectedCollectionViewMenuItemIndex]);
			}
		}

		void SetupSubMenuItemCollectionView()
		{
			VM.ItemsPerRow = 3;
			this.BaseView.MenuCollectionView.RegisterNibForCell (UINib.FromName ("MenuGridItem", NSBundle.MainBundle), MenuGridItem.Key);
			_collectionSource = new CollectionSource (this.BaseView.MenuCollectionView, MenuGridItem.Key);
			_collectionSource.VM = VM; 
			this.BaseView.MenuCollectionView.Source = _collectionSource;
			this.BaseView.MenuCollectionView.WeakDelegate = null;
//			this.BaseView.MenuCollectionView.CollectionViewLayout = null;

			var set = this.CreateBindingSet<MainMenuView, MainMenuViewModel> ();
			set.Bind (_collectionSource).To (vm => vm.SubMenuItems);
			set.Bind (_collectionSource).For (s => s.SelectionChangedCommand).To (vm => vm.SubMenuItemSelectedCommand);
			set.Apply ();
		}

		void SetupProgramsCollectionView ()
		{
			VM.ItemsPerRow = 4;
			this.BaseView.MenuCollectionView.RegisterNibForCell (UINib.FromName ("MovieViewCell", NSBundle.MainBundle), MovieViewCell.Key);
			this.BaseView.MenuCollectionView.RegisterClassForSupplementaryView (typeof(CollectionHeader), UICollectionElementKindSection.Header, headerId);

			_collectionSource = new MovieSource (this.BaseView.MenuCollectionView);
			this.BaseView.MenuCollectionView.Source = _collectionSource;
			this.BaseView.MenuCollectionView.WeakDelegate = new MovieDelegate ();

			var set = this.CreateBindingSet<MainMenuView, MainMenuViewModel> ();
			set.Bind (_collectionSource).To (vm => vm.ProgramSections);
			set.Bind (_collectionSource).For (s => s.SelectionChangedCommand).To (vm => vm.SubMenuItemSelectedCommand);
			set.Apply ();

			this.BaseView.MenuCollectionView.ReloadData ();


		}

		public class TableSource : MvxSimpleTableViewSource
		{
			private UITableView _tableView;
			public new UITableView TableView { get { return _tableView; } }

			public TableSource (UITableView tableView) : base (tableView, "MenuTableViewCell", "MenuTableViewCell")
			{
				_tableView = tableView;
			}

			public override nfloat GetHeightForRow (UITableView tableView, NSIndexPath indexPath)
			{
				return 48;
			}

			public override void RowSelected (UITableView tableView, NSIndexPath indexPath)
			{
				base.RowSelected (tableView, indexPath);
			}

		}

		public class MovieSource : CollectionSource
		{
			public MovieSource (UICollectionView collectionView)
				: base (collectionView, MovieViewCell.Key)
			{
			}

			public override nint NumberOfSections (UICollectionView collectionView)
			{
				return (ItemsSource as ObservableCollection<ProgramSection>).Count;
			}

			public override UICollectionReusableView GetViewForSupplementaryElement (UICollectionView collectionView, NSString elementKind, NSIndexPath indexPath)
			{
				var headerView = (CollectionHeader)collectionView.DequeueReusableSupplementaryView (elementKind, headerId, indexPath);
				headerView.Text = (ItemsSource as ObservableCollection<ProgramSection>)[indexPath.Section].SectionTitle; // TODO make this dynamic?
				return headerView;
			}

			public override nint GetItemsCount (UICollectionView collectionView, nint section)
			{
				return (nint)(ItemsSource as ObservableCollection<ProgramSection>)[(int)section].Programs.Count;
			}

			protected override object GetItemAt (NSIndexPath indexPath)
			{
				var program = (ItemsSource as ObservableCollection<ProgramSection>)[indexPath.Section].Programs[indexPath.Row];
				return program;
			}

			public override void ItemSelected (UICollectionView collectionView, NSIndexPath indexPath)
			{

				Mvx.Trace("SELECTED");

				base.ItemSelected (collectionView, indexPath);
			}

			//			public override void WillDisplaySupplementaryView (UICollectionView collectionView, UICollectionReusableView view, string elementKind, NSIndexPath indexPath)
			//			{
			//				throw new System.NotImplementedException ();
			//			}
		}

		public class CollectionSource : MvxCollectionViewSource
		{

			private UICollectionView _collectionView;
			public new UICollectionView CollectionView { get { return _collectionView; } }

			private MainMenuViewModel _vm;

			public MainMenuViewModel VM {
				get { return _vm; }
				set { _vm = value; }
			}

			public CollectionSource (UICollectionView collectionView, NSString defaultCellIdentifier) : base (collectionView, defaultCellIdentifier)
			{

				_collectionView = collectionView;
			}



			public override void ItemSelected (UICollectionView collectionView, NSIndexPath indexPath)
			{

				_vm.SelectedCollectionViewMenuItemIndex = indexPath.Row;

				Mvx.Trace("SELECTED");

				base.ItemSelected (collectionView, indexPath);
			}

		}

		public class MovieDelegate : UICollectionViewDelegateFlowLayout
		{


			public override CGSize GetSizeForItem (UICollectionView collectionView, UICollectionViewLayout layout, NSIndexPath indexPath)
			{
				return new CGSize (164, 240);//135
			}

			public override nfloat GetMinimumInteritemSpacingForSection (UICollectionView collectionView, UICollectionViewLayout layout, nint section)
			{
				return 0;
			}

			public override UIEdgeInsets GetInsetForSection (UICollectionView collectionView, UICollectionViewLayout layout, nint section)
			{
				return new UIEdgeInsets (0, 0, 0, 10);
			}

			public override nfloat GetMinimumLineSpacingForSection (UICollectionView collectionView, UICollectionViewLayout layout, nint section)
			{
				return 0;
			}

			public override CGSize GetReferenceSizeForHeader (UICollectionView collectionView, UICollectionViewLayout layout, nint section)
			{
				return new CGSize (575, 48);
			}
		}

		public class CollectionHeader : UICollectionReusableView
		{
			UILabel label;

			public string Text {
				get {
					return label.Text;
				}
				set {
					label.Text = value;
					SetNeedsDisplay ();
				}
			}

			[Export ("initWithFrame:")]
			public CollectionHeader (CGRect frame) : base (frame)
			{
				label = new UILabel () {
					Frame = new CGRect (0, 0, 300, 50), 
					BackgroundColor = UIColor.Clear
				};
				AddSubview (label);

				BackgroundColor = UIColor.Clear;

				StyleHelper.StyleLabel (label, 28, 0xFFFFFF, true);

			}
		}

		protected override void Dispose (bool disposing)
		{
			Destroy();

			// Brute force, remove everything
			foreach (var view in Subviews)
				view.RemoveFromSuperview ();
			base.Dispose (disposing);
		}


		public void Destroy(){
			BindingContext.ClearAllBindings();
			VM.Destroy();
			_listener.Clear();
		}
	}


}