Announcing widget errors and warnings

tools/Dashboard/DevHome.Dashboard/ViewModels/WidgetViewModel.cs

@@ -2,6 +2,10 @@
 // Licensed under the MIT License.
 
 using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
 using System.Threading.Tasks;
 using AdaptiveCards.ObjectModel.WinUI3;
 using AdaptiveCards.Rendering.WinUI3;
@@ -42,6 +46,7 @@ public partial class WidgetViewModel : ObservableObject
 
     private readonly DispatcherQueue _dispatcherQueue;
     private readonly WidgetAdaptiveCardRenderingService _renderingService;
+    private readonly IScreenReaderService _screenReaderService;
 
     private RenderedAdaptiveCard _renderedCard;
 
@@ -98,9 +103,11 @@ public WidgetViewModel(
         WidgetSize widgetSize,
         ComSafeWidgetDefinition widgetDefinition,
         WidgetAdaptiveCardRenderingService adaptiveCardRenderingService,
+        IScreenReaderService screenReaderService,
         DispatcherQueue dispatcherQueue)
     {
         _renderingService = adaptiveCardRenderingService;
+        _screenReaderService = screenReaderService;
         _dispatcherQueue = dispatcherQueue;
 
         Widget = widget;
@@ -183,6 +190,7 @@ await Task.Run(async () =>
                     {
                         _renderedCard.Action += HandleAdaptiveAction;
                         WidgetFrameworkElement = _renderedCard.FrameworkElement;
+                        AnnounceWarnings(card.AdaptiveCard);
                     }
                     else
                     {
@@ -274,6 +282,8 @@ private Grid GetErrorCard(string error, string subError = null)
         };
         sp.Children.Add(errorText);
 
+        var errorTextToAnnounce = errorText.Text;
+
         if (subError is not null)
         {
             var subErrorText = new TextBlock
@@ -285,8 +295,11 @@ private Grid GetErrorCard(string error, string subError = null)
             };
 
             sp.Children.Add(subErrorText);
+            errorTextToAnnounce += $" {subErrorText.Text}";
         }
 
+        _screenReaderService.Announce(errorTextToAnnounce);
+
         grid.Children.Add(sp);
         return grid;
     }
@@ -339,4 +352,54 @@ public void UnsubscribeFromWidgetUpdates()
     {
         Widget.WidgetUpdated -= HandleWidgetUpdated;
     }
+
+    private void AnnounceWarnings(AdaptiveCard card)
+    {
+        // We are treating any text inside a container with the "Warning" style
+        // as an actual warning to be announced.
+        // For now, the only types of containers widgets use are Containers and Columns. In the future,
+        // we may add Caroussels, Tables and Facts to this list.
+        var containerTypes = new Dictionary<Type, string>
+        {
+            { typeof(AdaptiveContainer), "get_Items" },
+            { typeof(AdaptiveColumn), "get_Items" },
+            { typeof(AdaptiveColumnSet), "get_Columns" },
+        };
+
+        foreach (var element in card.Body)
+        {
+            SearchForWarning(element, containerTypes, false);
+        }
+    }
+
+    private void SearchForWarning(IAdaptiveCardElement element, Dictionary<Type, string> containerTypes, bool isInsideWarningContainer)
+    {
+        // We are only interested in plain texts. Buttons, Actions, Images
+        // and textboxes are all ignored. Including ActionSets and ImageSets.
+        if (element is AdaptiveTextBlock textBlock)
+        {
+            if (isInsideWarningContainer)
+            {
+                _screenReaderService.Announce(textBlock.Text);
+            }
+
+            return;
+        }
+
+        if (element is IAdaptiveContainerBase containerElement)
+        {
+            foreach (var containerType in containerTypes)
+            {
+                if (containerElement.GetType() == containerType.Key)
+                {
+                    MethodInfo itemsMethod = containerType.Key.GetMethod(containerType.Value, BindingFlags.Public | BindingFlags.Instance);
+
+                    foreach (var subelement in itemsMethod.Invoke(containerElement, null) as IEnumerable)
+                    {
+                        SearchForWarning((IAdaptiveCardElement)subelement, containerTypes, isInsideWarningContainer || (containerElement.Style == ContainerStyle.Warning));
+                    }
+                }
+            }
+        }
+    }
 }