Expandable Date Element for MT.D

gistfile1.cs

using System;
using MonoTouch.Dialog;
using MonoTouch.UIKit;
using System.Drawing;
using MonoTouch.Foundation;
using System.Collections.Generic;
using System.Globalization;

namespace TravelBudget
{
	public class StyledExpandableDateElement : Element, IElementSizing
	{
		public Action<DateTime> ValueChanged;
		DateTime _time = DateTime.Now;

		public DateTime Value
		{
			get { return _time; }
			set
			{
				if (_time != value)
				{
					_time = value;

					UpdateText ();

					if (ValueChanged != null)
						ValueChanged (Value);
				}
			}
		}

		UIDatePickerMode _mode;

		public UIDatePickerMode Mode
		{
			get { return _mode; }
			set
			{
				_mode = value;
			}
		}

		readonly RootElement _root;
		readonly Section _section;
		UIDatePicker _picker;
		Element _pickerElement;
		UITableViewCell _cell;
		bool minDateSet = false;
		bool maxDateSet = false;
		DateTime maxDate = DateTime.MaxValue;
		DateTime minDate = DateTime.MinValue;

		public DateTime MaxDate
		{ 
			get
			{
				return maxDate;
			}
			set
			{
				maxDate = value;
				maxDateSet = true;
			}
		}

		public DateTime MinDate
		{ 
			get
			{
				return minDate;
			}
			set
			{
				minDate = value;
				minDateSet = true;
			}
		}

		public StyledExpandableDateElement (string caption, DateTime dateTime, UIDatePickerMode mode, RootElement root, Section section) : base (caption)
		{
			Mode = mode;

			//Handle issues where time values are set and the date isn't. This leads to odd behavor.
			if (mode == UIDatePickerMode.Time)
			{
				if (dateTime.Year < 2000)
				{
					var currentDate = DateTime.Now;
					dateTime = new DateTime (currentDate.Year, currentDate.Month, currentDate.Day, dateTime.Hour, dateTime.Minute, dateTime.Second);
				}
			}

			Value = dateTime;
			_root = root;
			_section = section;
		}

		public override UITableViewCell GetCell (UITableView tv)
		{
			const string cellKey = "StyledExpandableDateElement";
			var cell = tv.DequeueReusableCell (cellKey);

			if (cell == null)
			{
				cell = new UITableViewCell (UITableViewCellStyle.Value1, cellKey);
				cell.TextLabel.Font = UIFont.SystemFontOfSize (17f);
				cell.TextLabel.TextColor = UIColor.Black;
				cell.TextLabel.AdjustsFontSizeToFitWidth = true;
				cell.TextLabel.MinimumScaleFactor = .5f;
				cell.Accessory = UITableViewCellAccessory.None;
				cell.SelectionStyle = UITableViewCellSelectionStyle.None;

				cell.DetailTextLabel.Font = UIFont.SystemFontOfSize (16f);
				cell.DetailTextLabel.TextColor = UIColor.LightGray;
				cell.DetailTextLabel.AdjustsFontSizeToFitWidth = true;
				cell.DetailTextLabel.MinimumScaleFactor = .5f;
			}

			_cell = cell;

			cell.TextLabel.Text = Caption;
			UpdateText ();

			return cell;

		}

		public float GetHeight (UITableView tableView, NSIndexPath indexPath)
		{
			return 44;
		}

		protected internal NSDateFormatter fmt = new NSDateFormatter () {
			DateStyle = NSDateFormatterStyle.Medium,
			TimeZone = NSTimeZone.LocalTimeZone
		};
		protected internal NSDateFormatter fullFormat = new NSDateFormatter () {
			DateFormat = "yyyy-MM-dd'|'HH:mm",
			TimeZone = NSTimeZone.LocalTimeZone
		};

		public void Contract()
		{
			if (_picker != null)
			{
				_section.Remove (_pickerElement);
				//_root.Reload (_section, UITableViewRowAnimation.Fade);
				_pickerElement.Dispose ();
				_picker.Dispose ();
				_pickerElement = null;
				_picker = null;
				_cell.DetailTextLabel.TextColor = UIColor.LightGray;
			}
		}

		public override void Selected (DialogViewController dvc, UITableView tableView, NSIndexPath path)
		{
			base.Selected (dvc, tableView, path);

			_root.TableView.EndEditing (true);

			if (_picker == null)
			{

				var otherExpandableItems = new List<StyledExpandableDateElement> ();
				foreach(var element in _section)
				{
					if (element is StyledExpandableDateElement && element != this)
					{
						otherExpandableItems.Add (element as StyledExpandableDateElement);
					}
				}

				foreach(var element in otherExpandableItems)
				{
					element.Contract ();
				}



				int left = 0;
				_picker = new UIDatePicker (new RectangleF (left, 0, 320, 200)) {
					Mode = Mode,
					Date = Value,
					TimeZone = NSTimeZone.LocalTimeZone
				};
				_picker.TimeZone = NSTimeZone.LocalTimeZone;

				if (minDateSet)
					_picker.MinimumDate = minDate;
				if (maxDateSet)
					_picker.MaximumDate = maxDate;

				_picker.BackgroundColor = UIColor.White;

				_picker.ValueChanged += (object sender, EventArgs e) =>
				{

					UIDatePicker picker = sender as UIDatePicker;


					string internalAsString = fullFormat.ToString (_picker.Date);

					DateTime dt;
					if (DateTime.TryParseExact (internalAsString, "yyyy-MM-dd|HH:mm", CultureInfo.InvariantCulture, DateTimeStyles.AssumeLocal, out dt))
					{
						Value = dt;
					} else
					{
						Value = _picker.Date;
					}

					Console.WriteLine("Value: " + Value);
				};

				_cell.DetailTextLabel.TextColor = UIColor.Blue;

				_pickerElement = new UIViewElement ("", _picker, true);

				var idx = _section.Elements.IndexOf (this);

				var elements = new List<Element> {
					_pickerElement
				};

				_section.Insert (idx + 1, UITableViewRowAnimation.Top, elements);
				_root.TableView.ScrollToRow (IndexPath, UITableViewScrollPosition.Bottom, true);
			} else
			{
				Contract ();

				_root.TableView.ScrollToRow (IndexPath, UITableViewScrollPosition.Middle, true);
			}
		}

		void UpdateText ()
		{
			string text;
			switch (Mode)
			{
				case UIDatePickerMode.Date:
					text = Value.ToShortDateString ();
					break;
				case UIDatePickerMode.DateAndTime:
					text = Value.ToShortDateString () + " " + Value.ToShortTimeString ();
					break;
				case UIDatePickerMode.Time:
					text = Value.ToShortTimeString ();
					break;
				default:
					text = "";
					break;
			}

			if (_cell != null)
			{
				_cell.DetailTextLabel.Text = text;
			}

		}

		protected override void Dispose (bool disposing)
		{
			if (disposing)
			{
				if (_picker != null)
				{
					_picker.Dispose ();
				}

				if (_pickerElement != null)
				{
					_pickerElement.Dispose ();
				}

				_cell = null;

			}
			base.Dispose (disposing);
		}
	}
}