Added some tests

samples/Myra.Samples.Layout2D/MyraSamplesLayout2D.cs

@@ -78,7 +78,7 @@ protected override void LoadContent()
 			{
 				Text = "Calc"
 			};
-			btnA.Click += (object sender, EventArgs e) => { btnB.Layout2d.Expresion = (_desktop.GetWidgetByID("Expression") as TextBox).Text; _desktop.InvalidateLayout(); _desktop.UpdateLayout(); };
+			btnA.Click += (object sender, EventArgs e) => { btnB.Layout2d.Expresion = (_desktop.FindChild("Expression") as TextBox).Text; _desktop.InvalidateLayout(); _desktop.UpdateLayout(); };
 			panel.Widgets.Add(btnA);
 
 			g.Widgets.Add(panel);

src/Myra.Tests/GridTests.cs

@@ -0,0 +1,53 @@
+using Microsoft.Xna.Framework;
+using Myra.Graphics2D.UI;
+using NUnit.Framework;
+
+namespace Myra.Tests
+{
+	[TestFixture]
+	public class GridTests
+	{
+		private static Project LoadFromResource(string name)
+		{
+			var xml = typeof(GridTests).Assembly.ReadResourceAsString("Resources.GridTests." + name);
+
+			return Project.LoadFromXml(xml);
+		}
+
+		[Test]
+		public static void TestSimpleProportionsPart()
+		{
+			var project = LoadFromResource("SimpleProportionsPart.xmmp");
+			var grid = (Grid)project.Root;
+
+			grid.Arrange(new Rectangle(0, 0, 400, 400));
+
+			Assert.AreEqual(100, grid.Widgets[0].ContainerBounds.Width);
+			Assert.AreEqual(200, grid.Widgets[0].ContainerBounds.Height);
+			Assert.AreEqual(300, grid.Widgets[1].ContainerBounds.Width);
+			Assert.AreEqual(200, grid.Widgets[1].ContainerBounds.Height);
+			Assert.AreEqual(100, grid.Widgets[2].ContainerBounds.Width);
+			Assert.AreEqual(200, grid.Widgets[2].ContainerBounds.Height);
+			Assert.AreEqual(300, grid.Widgets[3].ContainerBounds.Width);
+			Assert.AreEqual(200, grid.Widgets[3].ContainerBounds.Height);
+		}
+
+		[Test]
+		public static void TestSimpleAutoFill()
+		{
+			var project = LoadFromResource("SimpleAutoFill.xmmp");
+			var grid = (Grid)project.Root;
+
+			grid.Arrange(new Rectangle(0, 0, 400, 500));
+
+			Assert.AreEqual(100, grid.Widgets[0].ContainerBounds.Width);
+			Assert.AreEqual(450, grid.Widgets[0].ContainerBounds.Height);
+			Assert.AreEqual(300, grid.Widgets[1].ContainerBounds.Width);
+			Assert.AreEqual(450, grid.Widgets[1].ContainerBounds.Height);
+			Assert.AreEqual(100, grid.Widgets[2].ContainerBounds.Width);
+			Assert.AreEqual(50, grid.Widgets[2].ContainerBounds.Height);
+			Assert.AreEqual(300, grid.Widgets[3].ContainerBounds.Width);
+			Assert.AreEqual(50, grid.Widgets[3].ContainerBounds.Height);
+		}
+	}
+}

src/Myra.Tests/Res.cs

@@ -0,0 +1,65 @@
+using System.IO;
+using System.Reflection;
+using System;
+
+namespace Myra.Tests
+{
+	internal static class Res
+	{
+		/// <summary>
+		/// Open assembly resource stream by relative name
+		/// </summary>
+		/// <param name="assembly"></param>
+		/// <param name="path"></param>
+		/// <returns></returns>
+		public static Stream OpenResourceStream(this Assembly assembly, string path)
+		{
+			// Once you figure out the name, pass it in as the argument here.
+			path = assembly.GetName().Name + "." + path;
+			var stream = assembly.GetManifestResourceStream(path);
+			if (stream == null)
+			{
+				throw new Exception($"Could not find resource at path '{path}'");
+			}
+
+			return stream;
+		}
+
+		/// <summary>
+		/// Reads assembly resource as byte array by relative name
+		/// </summary>
+		/// <param name="assembly"></param>
+		/// <param name="path"></param>
+		/// <returns></returns>
+		public static byte[] ReadResourceAsBytes(this Assembly assembly, string path)
+		{
+			var ms = new MemoryStream();
+			using (var input = assembly.OpenResourceStream(path))
+			{
+				input.CopyTo(ms);
+
+				return ms.ToArray();
+			}
+		}
+
+		/// <summary>
+		/// Reads assembly resource as string by relative name
+		/// </summary>
+		/// <param name="assembly"></param>
+		/// <param name="path"></param>
+		/// <returns></returns>
+		public static string ReadResourceAsString(this Assembly assembly, string path)
+		{
+			string result;
+			using (var input = assembly.OpenResourceStream(path))
+			{
+				using (var textReader = new StreamReader(input))
+				{
+					result = textReader.ReadToEnd();
+				}
+			}
+
+			return result;
+		}
+	}
+}

src/Myra.Tests/Resources/GridTests/SimpleAutoFill.xmmp

@@ -0,0 +1,16 @@
+<Project>
+  <Grid>
+    <Grid.ColumnsProportions>
+      <Proportion Type="Auto" />
+      <Proportion Type="Fill" />
+    </Grid.ColumnsProportions>
+    <Grid.RowsProportions>
+      <Proportion Type="Fill" />
+      <Proportion Type="Auto" />
+    </Grid.RowsProportions>
+    <Label Text="Test" Width="100" Height="50" />
+    <Label Text="Test" Width="100" Height="50" Grid.Column="1" />
+    <Label Text="Test" Width="100" Height="50" Grid.Row="1" />
+    <Label Text="Test" Width="100" Height="50" Grid.Column="1" Grid.Row="1" />
+  </Grid>
+</Project>

src/Myra.Tests/Resources/GridTests/SimpleProportionsPart.xmmp

@@ -0,0 +1,16 @@
+<Project>
+  <Grid>
+    <Grid.ColumnsProportions>
+      <Proportion Type="Part" Value="1" />
+      <Proportion Type="Part" Value="3" />
+    </Grid.ColumnsProportions>
+    <Grid.RowsProportions>
+      <Proportion Type="Part" Value="1" />
+      <Proportion Type="Part" Value="1" />
+    </Grid.RowsProportions>
+    <Label Text="Test" />
+    <Label Text="Test" Grid.Column="1" />
+    <Label Text="Test" Grid.Row="1" />
+    <Label Text="Test" Grid.Column="1" Grid.Row="1" />
+  </Grid>
+</Project>

src/Myra/Graphics2D/UI/Project.cs

@@ -232,7 +232,7 @@ public static Project LoadFromXml<T>(XDocument xDoc, AssetManager assetManager =
 
 			var result = new Project();
 
-			if (stylesheet != null)
+			if (stylesheetPathAttr != null)
 			{
 				if (assetManager == null)
 				{