Demo code binding to a view model, styles, and layout written during live session

curtis-demo.cs

using System;
using Eto.Forms;
using Eto.Drawing;
using System.Windows.Input;
using System.Runtime.CompilerServices;
using System.ComponentModel;
using System.Collections.Generic;
using System.Collections.ObjectModel;

namespace EtoApp2
{

	public static class StyleID
	{
		public static class StackLayout
		{
			public const string Top = "Rhino.top";
		}
	}

	public partial class MainForm
	{
		static MainForm()
		{
			//Eto.Style.Add<Control>(null, c => c.BackgroundColor = Colors.Red);
			Eto.Style.Add<Label>(null, label =>
			{
				label.VerticalAlignment = VerticalAlignment.Center;
			});
			Eto.Style.Add<Label>(StyleID.StackLayout.Top, label =>
			{
				label.VerticalAlignment = VerticalAlignment.Top;
				label.BackgroundColor = Colors.Blue;
			});
		}

		public MainForm()
		{
			InitializeComponent();
		}
	}

	enum Gender
	{
		Male,
		Female,
		X,
		Unset
	}

	class MyDropDownItem
	{
		public string Name { get; set; }
	}

	class MyTreeItem : TreeGridItem
	{
		public Image Image { get; set; }
		public string Name { get; set; }
	}

	class MyModel : INotifyPropertyChanged
	{
		Command saveCommand;
		string firstName;
		string lastName;
		Gender gender;
		bool useHomeAddress;
		ObservableCollection<MyDropDownItem> collection;
		TreeGridItemCollection treeCollection;
		Image image;

		public static Dictionary<Gender, string> GenderStrings = new Dictionary<Gender, string>
			{
				{ Gender.Male, "Male!" },
				{ Gender.Unset, "Unset" },
				{ Gender.Female, "Female!" },
				{ Gender.X, "X!" }
			};


		public MyModel()
		{
			saveCommand = new Command((sender, e) =>
			{
				FirstName = "Something Else " + UseHomeAddress.ToString();

				collection.Add(new MyDropDownItem { Name = "Item " + collection.Count });
			});
			collection = new ObservableCollection<MyDropDownItem>();
			collection.Add(new MyDropDownItem { Name = "First Item" });

			treeCollection = new TreeGridItemCollection();
			treeCollection.Add(new MyTreeItem { Name = "First Node", Children = { } });

			saveCommand.Enabled = false;
		}

		float logicalPixelSize;
		public float LogicalPixelSize
		{
			get { return logicalPixelSize; }
			set
			{
				if (logicalPixelSize != value)
				{
					logicalPixelSize = value;
					OnPropertyChanged();
					OnPropertyChanged(nameof(Image));
				}
			}
		}

		public Image Image
		{
			get { return image; }
		}

		Size imageSize;
		public Size ImageSize
		{
			get { return imageSize; }
			set
			{
				if (imageSize != value)
				{
					imageSize = value;

					List<IconFrame> frames = new List<IconFrame>();
					for (int i = 1; i <= 3; i++)
					{
						var bitmap = new Bitmap(value.Width * i, value.Height * i, PixelFormat.Format32bppRgba);
						using (var g = new Graphics(bitmap))
						{
							g.ScaleTransform(i);
							Color color = Colors.White;
							if (i == 1) color = Colors.Red;
							if (i == 2) color = Colors.Green;
							if (i == 3) color = Colors.Blue;
							g.DrawLine(color, PointF.Empty, new PointF(value.Width, value.Height));
							g.DrawText(Fonts.Sans(20), Colors.Black, new PointF(100, 100), value.ToString());
						}

						frames.Add(new IconFrame(i, bitmap));
					}

					var icon = new Icon(frames);
					image = icon;

					OnPropertyChanged();
					OnPropertyChanged(nameof(Image));
				}
			}
		}


		public TreeGridItemCollection MyTreeItems
		{
			get { return treeCollection; }
		}

		public Gender Gender
		{
			get { return gender; }
			set
			{
				if (gender != value)
				{
					gender = value;
					OnPropertyChanged();
				}
			}
		}

		public bool UseHomeAddress
		{
			get { return useHomeAddress; }
			set
			{
				if (useHomeAddress != value)
				{
					useHomeAddress = value;
					saveCommand.Enabled = value;
					OnPropertyChanged();
				}
			}
		}

		public string FirstName
		{
			get { return firstName; }
			set
			{
				if (firstName != value)
				{
					firstName = value;
					OnPropertyChanged();
					OnPropertyChanged("FullName");
				}
			}
		}

		public string FullName
		{
			get { return FirstName + " " + LastName; }
		}

		public string LastName
		{
			get { return lastName; }
			set
			{
				if (lastName != value)
				{
					lastName = value;
					OnPropertyChanged();
					OnPropertyChanged("FullName");
				}
			}
		}

		public IList<MyDropDownItem> MyItems
		{
			get
			{
				return collection;
			}
		}

		public ICommand SaveCommand
		{
			get
			{
				return saveCommand;
			}
		}

		public event PropertyChangedEventHandler PropertyChanged;

		void OnPropertyChanged([CallerMemberName] string propertyName = null)
		{
			if (PropertyChanged != null)
				PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
		}
	}

	partial class MainForm : Form
	{
		void InitializeComponent()
		{
			Title = "My Eto Form";
			//ClientSize = new Size(400, 350);

			var spacing = 5;

			var firstNameTextBox = new TextBox();
			//firstNameTextBox.TextBinding.BindDataContext((MyModel m) => m.FirstName);
			firstNameTextBox.BindDataContext(c => c.Text, (MyModel m) => m.FirstName);

			var lastNameTextBox = new TextBox();
			lastNameTextBox.TextBinding.BindDataContext((MyModel m) => m.LastName);

			var fullNameLabel = new Label { };
			fullNameLabel.TextBinding.BindDataContext((MyModel m) => m.FullName);

			var saveButton = new Button { Text = "Save" };
			saveButton.BindDataContext(c => c.Command, (MyModel m) => m.SaveCommand);


			var genderDropDown = new EnumRadioButtonList<Gender>();
			genderDropDown.Orientation = Orientation.Vertical;
			genderDropDown.GetText = (gender) => MyModel.GenderStrings[gender];
			genderDropDown.SortAlphabetically = true;
			//genderDropDown.AddValue += (sender, e) => e.ShouldAdd = e.Value != Gender.X;
			genderDropDown.BindDataContext(c => c.SelectedValue, (MyModel m) => m.Gender);

			var dropDown = new DropDown();
			dropDown.ItemTextBinding = Binding.Property((MyDropDownItem m) => m.Name);
			dropDown.BindDataContext(c => c.DataStore, (MyModel m) => m.MyItems);

			var checkBox = new CheckBox { Text = "Use Home Address" };
			//checkBox.BindDataContext(c => c.Checked, (MyModel m) => m.UseHomeAddress);
			checkBox.CheckedBinding.BindDataContext((MyModel m) => m.UseHomeAddress);

			var radioButtonList = new RadioButtonList();
			radioButtonList.Items.Add("Item 1");

			var radioStack = new StackLayout { Orientation = Orientation.Horizontal };
			RadioButton controller = null;
			for (int i = 0; i < 10; i++)
			{
				var radio = new RadioButton(controller);
				radio.Text = "Radio " + i;
				//controller = controller ?? radio;
				radioStack.Items.Add(radio);
			}

			var panel = new Panel();
			var imageView = new ImageView();
			panel.BindDataContext(c => c.Size, (MyModel m) => m.ImageSize);
			imageView.BindDataContext(c => c.Image, (MyModel m) => m.Image);

			panel.Content = imageView;


			var gridView = new TreeGridView { Height = 300 };
			gridView.Columns.Add(new GridColumn
			{
				HeaderText = "Some Text",
				Editable = true,
				DataCell = new ImageTextCell { 
					ImageBinding = Binding.Property((MyTreeItem m) => m.Image),  
					TextBinding = Binding.Property((MyTreeItem m) => m.Name) 
				}
			});
			gridView.Columns.Add(new GridColumn
			{
				HeaderText = "Some Text2",
				DataCell = new ImageTextCell
				{
					ImageBinding = Binding.Property((MyTreeItem m) => m.Image),
					TextBinding = Binding.Property((MyTreeItem m) => m.Name)
				}
			});

			UpdateBindings(BindingUpdateMode.Destination);

			var image = Icon.FromResource("EtoApp2.TestIcon.ico");
			var treeCollection = new TreeGridItemCollection();
			treeCollection.Add(new MyTreeItem {
				Name = "First Node",
				Image = image,
				Expanded = true,
				Children = {
					new MyTreeItem { Name = "Child Item", Image = image }
				} 
			});
			gridView.DataStore = treeCollection;
			//gridView.BindDataContext(c => c.DataStore, (MyModel m) => m.MyTreeItems);

			var model = new MyModel { FirstName = "Curtis", Gender = Gender.Unset };

			this.DataContext = model;

			Content = new StackLayout
			{
				Padding = 10,
				Spacing = spacing,
				DataContext = model,
				HorizontalContentAlignment = HorizontalAlignment.Stretch,
				Items =
				{
					fullNameLabel,
					new TableLayout {
						Spacing = new Size(spacing, spacing),
						Rows = {
							new TableRow(new Label { Text = "First Name"  }, firstNameTextBox),
							new TableRow("Last Name", lastNameTextBox),
							new TableRow(new Label { Text = "Gender", Style = StyleID.Top }, TableLayout.AutoSized(genderDropDown)),
							new TableRow(new TableCell(), checkBox),
							new TableRow(new TableCell(), dropDown),
							new TableRow(new TableCell(), radioStack),
						}
					},
					new StackLayoutItem(gridView, expand: true),
					new StackLayoutItem(panel, expand: true),
					new StackLayout
					{
						Orientation = Orientation.Horizontal,
						Spacing = 5,
						Items = {
							null,
							saveButton,
							new Button { Text = "Cancel" }
						  }
					}
			// add more controls here
		}
			};

			/*
			var stack = new StackLayout();
			stack.Spacing = 10;
			stack.Items.Add(new Label { Text = "Hello!" });
			*/

			/*
			StackLayout buttons;
			if (Eto.EtoEnvironment.Platform.IsMac)
			{
				buttons = new StackLayout
				{
					Orientation = Orientation.Horizontal,
					Spacing = 5,
					Items = {
						null,
						new Button { Text = "Save" },
						new Button { Text = "Cancel" }
					  }
				};
			}
			else {
				buttons = new StackLayout
				{
					Orientation = Orientation.Horizontal,
					Spacing = 5,
					Items = {
						null,
						new Button { Text = "Cancel" },
						new Button { Text = "Apply" },
					  }
				};
			}*/



		}

		protected override void OnLoadComplete(EventArgs e)
		{
			base.OnLoadComplete(e);
			Application.Instance.AsyncInvoke(() => MinimumSize = Size);
		}
	}

}