Add XAML example

Samples/ButtonXamlPage.xaml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="ButtonXaml.ButtonXamlPage">
+
+  <Button Text="Tap for click count!"
+          Clicked="OnButtonClicked" />
+  
+</ContentPage>

Samples/ButtonXamlPage.xaml.cs

@@ -0,0 +1,23 @@
+using System;
+using Xamarin.Forms;
+
+namespace ButtonXaml
+{
+    public partial class ButtonXamlPage
+    {
+        int count = 0;
+
+        public ButtonXamlPage()
+        {
+            InitializeComponent();
+        }
+
+        public void OnButtonClicked(object sender, EventArgs args)
+        {
+            count++;
+
+            ((Button)sender).Text = 
+                String.Format("{0} click{1}!", count, count == 1 ? "" : "s");
+        }
+    }
+}

Samples/ButtonXamlPageSample.cs

@@ -0,0 +1,17 @@
+using System;
+using Ooui;
+using Xamarin.Forms;
+
+namespace Samples
+{
+    public class ButtonXamlPageSample : ISample
+    {
+        public string Title => "Xamarin.Forms Button XAML";
+
+        public Ooui.Element CreateElement ()
+        {
+            var page = new ButtonXaml.ButtonXamlPage ();
+            return page.GetOouiElement ();
+        }
+    }
+}

Samples/Samples.csproj

@@ -8,6 +8,9 @@
   <ItemGroup>
     <PackageReference Include="Xamarin.Forms" Version="2.4.0.38779" />
   </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="**/*" />
+  </ItemGroup>
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFramework>netcoreapp2.0</TargetFramework>