Shows how to use a DropDown control with per-item list of items.

DropDownInCustomCell.cs

using System;
using Eto.Forms;
using Eto.Drawing;

namespace Eto.Test
{

  	class MyItem
	{
		public int SelectedItem { get; set; }

		public ListItemCollection Items { get; set; }
	}

	public class TestCustomCellForm : Form
	{
		public TestCustomCellForm()
		{
			// create the custom cell
			var cell = new CustomCell();
			cell.CreateCell = e =>
			{
				var dropDown = new DropDown();
				dropDown.BindDataContext(c => c.DataStore, (MyItem m) => m.Items);
				dropDown.SelectedIndexBinding.BindDataContext((MyItem m) => m.SelectedItem);
				return dropDown;
			};
			cell.Paint += (sender, e) =>
			{
				// for GTK and WinForms
				var item = e.Item as MyItem;
				if (item != null)
				{
					e.Graphics.DrawText(SystemFonts.Default(), SystemColors.ControlText, 0, 0, "");
				}
			};

			// create the grid
			var grid = new GridView { Size = new Size(300, 300) };
			grid.Columns.Add(new GridColumn { HeaderText = "Custom DropDown", Editable = true, DataCell = cell });


			// create some drop down item lists
			var items1 = new ListItemCollection(new[] { 
				new ListItem { Text = "Item 1" },
				new ListItem { Text = "Item 2" }
			});

			var items2 = new ListItemCollection(new[] { 
				new ListItem { Text = "Item 1" },
				new ListItem { Text = "Item 2" },
				new ListItem { Text = "Item 3" }
			});

			// set the datastore of the grid
			grid.DataStore = new List<MyItem>()
			{
				new MyItem { SelectedItem = 0, Items = items1 },
				new MyItem { SelectedItem = 2, Items = items2 },
				new MyItem { SelectedItem = 1, Items = items1 }
			};

			Content = grid;
		}
	}

}