Platform now subscribes and unsubscribes to Alert Messages that come in from the Xamarin.Forms Message Center. Implemented a basic modal using the included bootstrap styles

Ooui.Forms/Platform.cs

@@ -1,11 +1,12 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Ooui.Forms.Renderers;
 using Xamarin.Forms;
 using Xamarin.Forms.Internals;
+using System.Web;
 
-namespace Ooui.Forms
+namespace Ooui.Forms
 {
     public class Platform : BindableObject, IPlatform, INavigation, IDisposable
     {
@@ -31,6 +32,84 @@ namespace Ooui.Forms
         public Platform ()
         {
             _renderer = new PlatformRenderer (this);
+
+            MessagingCenter.Subscribe(this, Page.AlertSignalName, (Page sender, AlertArguments arguments) =>
+            {
+                var alert = new Div
+                {
+                    ClassName = "modal-dialog"
+                };
+
+                var content = new Div
+                {
+                    ClassName = "modal-content"
+                };
+
+                var header = new Div
+                {
+                    ClassName = "modal-header"
+                };
+
+                var closeButton = new Button
+                {
+                    ClassName = "close"
+                };
+
+                closeButton.AppendChild(new Span(HttpUtility.HtmlDecode("×")));
+                closeButton.Clicked += CloseAlert;
+
+                var h4 = new Heading(4)
+                {
+                    Text = arguments.Title
+                };
+
+                header.AppendChild(closeButton);
+                header.AppendChild(h4);
+
+                content.AppendChild(header);
+                content.AppendChild(new Div()
+                {
+                    ClassName = "modal-body",
+                    Text = arguments.Message
+                });
+
+                if (!string.IsNullOrEmpty(arguments.Cancel))
+                {
+                    var footer = new Div()
+                    {
+                        ClassName = "modal-footer"
+                    };
+
+                    var cancel = new Button(arguments.Cancel)
+                    {
+                        ClassName = "btn btn-default"
+                    };
+                    cancel.Clicked += CloseAlert;
+
+                    footer.AppendChild(cancel);
+
+                    if (!string.IsNullOrEmpty(arguments.Accept))
+                    {
+                        var accept = new Button(arguments.Accept)
+                        {
+                            ClassName = "btn btn-default"
+                        };
+                        accept.Clicked += CloseAlert;
+
+                        footer.AppendChild(accept);
+                    }
+
+                    content.AppendChild(footer);
+                }
+
+                alert.AppendChild(content);
+                _renderer.AppendChild(alert);
+
+                void CloseAlert(object s, EventArgs e)
+                {
+                    _renderer.RemoveChild(alert);
+                }
+            });
         }
 
         void IDisposable.Dispose ()
@@ -70,10 +149,10 @@ namespace Ooui.Forms
 
         public SizeRequest GetNativeSize (VisualElement view, double widthConstraint, double heightConstraint)
         {
-            var renderView = GetRenderer (view);
-            if (renderView == null || renderView.NativeView == null)
-                return new SizeRequest (Size.Zero);
-
+            var renderView = GetRenderer (view);
+            if (renderView == null || renderView.NativeView == null)
+                return new SizeRequest (Size.Zero);
+
             return renderView.GetDesiredSize (widthConstraint, heightConstraint);
         }
 
@@ -173,5 +252,5 @@ namespace Ooui.Forms
         {
             throw new NotImplementedException ();
         }
-    }
-}
+    }
+}