Revert "Remove error page" (#79)

Dreamescaper · Nov 9, 2022 · 34cf6e2 · 34cf6e2
1 parent 6b06da5
commit 34cf6e2
Show file tree

Hide file tree

Showing 4 changed files with 75 additions and 10 deletions.
diff --git a/src/BlazorBindings.Core/NativeComponentRenderer.cs b/src/BlazorBindings.Core/NativeComponentRenderer.cs
@@ -6,7 +6,6 @@
 using Microsoft.Extensions.Logging;
 using System;
 using System.Collections.Generic;
-using System.Runtime.ExceptionServices;
 using System.Threading.Tasks;
 
 namespace BlazorBindings.Core
@@ -121,11 +120,6 @@ protected override Task UpdateDisplayAsync(in RenderBatch renderBatch)
             return Task.CompletedTask;
         }
 
-        protected override void HandleException(Exception exception)
-        {
-            ExceptionDispatchInfo.Throw(exception);
-        }
-
         public void RegisterEvent(ulong eventHandlerId, Action<ulong> unregisterCallback)
         {
             if (eventHandlerId == 0)

diff --git a/src/BlazorBindings.Maui/ErrorPageHelper.cs b/src/BlazorBindings.Maui/ErrorPageHelper.cs
@@ -0,0 +1,67 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+using Microsoft.Maui;
+using Microsoft.Maui.Controls;
+using Microsoft.Maui.Dispatching;
+using Microsoft.Maui.Graphics;
+using System;
+using System.Diagnostics;
+
+namespace BlazorBindings.Maui
+{
+    public static class ErrorPageHelper
+    {
+        public static void ShowExceptionPage(Exception exception)
+        {
+            Debug.WriteLine($"Fatal exception caught: '{exception?.GetType().Name}': '{exception?.Message}'");
+
+            Application.Current.Dispatcher.DispatchAsync(() =>
+            {
+                Application.Current.MainPage = GetErrorPageForException(exception);
+            });
+        }
+
+        private static ContentPage GetErrorPageForException(Exception exception)
+        {
+            var errorPage = new ContentPage()
+            {
+                BackgroundColor = Colors.White,
+                Title = "Unhandled exception",
+                Content = new StackLayout
+                {
+                    Margin = new Thickness(0, top: 30, 0, 0),
+                    Padding = 10,
+                    Children =
+                    {
+                        new Label
+                        {
+                            TextColor = Colors.Black,
+                            FontAttributes = FontAttributes.Bold,
+                            FontSize = Device.GetNamedSize(NamedSize.Large, typeof(Label)),
+                            Text = "Unhandled exception",
+                        },
+                        new Label
+                        {
+                            TextColor = Colors.Black,
+                            Text = exception?.Message,
+                        },
+                        new ScrollView
+                        {
+                            Content =
+                                new Label
+                                {
+                                    TextColor = Colors.Black,
+                                    FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
+                                    Text = exception?.StackTrace,
+                                },
+
+                        },
+                    },
+                },
+            };
+
+            return errorPage;
+        }
+    }
+}
diff --git a/src/BlazorBindings.Maui/MauiBlazorBindingsRenderer.cs b/src/BlazorBindings.Maui/MauiBlazorBindingsRenderer.cs
@@ -51,6 +51,11 @@ async Task<TComponent> AddComponentLocal()
             }
         }
 
+        protected override void HandleException(Exception exception)
+        {
+            ErrorPageHelper.ShowExceptionPage(exception);
+        }
+
         protected override ElementManager CreateNativeControlManager()
         {
             return new MauiBlazorBindingsElementManager();

diff --git a/src/BlazorBindings.UnitTests/MauiBlazorBindingsRendererTests.cs b/src/BlazorBindings.UnitTests/MauiBlazorBindingsRendererTests.cs
@@ -63,6 +63,7 @@ public async Task RenderToExistingControl_MultipleChildren()
         }
 
         [Test]
+        [Ignore("https://github.com/Dreamescaper/BlazorBindings.Maui/issues/42")]
         public void ShouldThrowExceptionIfHappenedDuringSyncRender()
         {
             void action() => _ = _renderer.AddComponent<ComponentWithException>(new NavigationPage());
@@ -78,10 +79,8 @@ public async Task RendererShouldHandleAsyncExceptions()
             var button = (MC.Button)contentView.Content;
             button.SendClicked();
 
-            await Task.Delay(50);
-
-            var exception = _renderer.Exceptions[0];
-            Assert.That(exception.Message, Is.EqualTo("HandleExceptionTest"));
+            Assert.That(() => _renderer.Exceptions, Is.Not.Empty.After(1000, 10));
+            Assert.That(_renderer.Exceptions[0].Message, Is.EqualTo("HandleExceptionTest"));
         }
 
         private static MC.Element GetChildContent(MC.Element container)