Implemented accessibilityLiveRegion

vnext/ReactUWP/Views/FrameworkElementViewManager.cpp

@@ -12,12 +12,14 @@
 #include <winrt/Windows.UI.Xaml.h>
 #include <winrt/Windows.UI.Xaml.Controls.h>
 #include <winrt/Windows.UI.Xaml.Automation.h>
+#include <winrt/Windows.UI.Xaml.Automation.Peers.h>
 #include <WindowsNumerics.h>
 
 namespace winrt {
 using namespace Windows::UI::Xaml;
 using namespace Windows::UI::Xaml::Controls;
 using namespace Windows::UI::Xaml::Automation;
+using namespace Windows::UI::Xaml::Automation::Peers;
 }
 
 namespace react { namespace uwp {
@@ -56,6 +58,7 @@ void FrameworkElementViewManager::TransferProperties(XamlView oldView, XamlView
 
   // Accessibility Properties
   TransferProperty(oldView, newView, winrt::AutomationProperties::NameProperty());
+  TransferProperty(oldView, newView, winrt::AutomationProperties::LiveSettingProperty());
   auto accessibilityView = winrt::AutomationProperties::GetAccessibilityView(oldView);
   winrt::AutomationProperties::SetAccessibilityView(newView, accessibilityView);
 
@@ -261,6 +264,7 @@ void FrameworkElementViewManager::UpdateProperties(ShadowNodeBase* nodeToUpdate,
         {
           element.ClearValue(winrt::AutomationProperties::NameProperty());
         }
+        AnnounceIfNeeded(element);
       }
       else if (propertyName == "accessible")
       {
@@ -270,6 +274,31 @@ void FrameworkElementViewManager::UpdateProperties(ShadowNodeBase* nodeToUpdate,
             winrt::AutomationProperties::SetAccessibilityView(element, winrt::Peers::AccessibilityView::Raw);
         }
       }
+      else if (propertyName == "accessibilityLiveRegion")
+      {
+        if (propertyValue.isString())
+        {
+          auto value = propertyValue.asString();
+
+          auto liveSetting = winrt::AutomationLiveSetting::Off;
+
+          if (value == "polite")
+          {
+            liveSetting = winrt::AutomationLiveSetting::Polite;
+          }
+          else if (value == "assertive")
+          {
+            liveSetting = winrt::AutomationLiveSetting::Assertive;
+          }
+
+          element.SetValue(winrt::AutomationProperties::LiveSettingProperty(), winrt::box_value(liveSetting));
+        }
+        else if (propertyValue.isNull())
+        {
+          element.ClearValue(winrt::AutomationProperties::LiveSettingProperty());
+        }
+        AnnounceIfNeeded(element);
+      }
       else if (propertyName == "testID")
       {
         if (propertyValue.isString())
@@ -317,4 +346,17 @@ void FrameworkElementViewManager::UpdateProperties(ShadowNodeBase* nodeToUpdate,
   Super::UpdateProperties(nodeToUpdate, reactDiffMap);
 }
 
+void FrameworkElementViewManager::AnnounceIfNeeded(winrt::FrameworkElement element)
+{
+  if (winrt::AutomationProperties::GetLiveSetting(element) != winrt::AutomationLiveSetting::Off
+    && !winrt::AutomationProperties::GetName(element).empty())
+  {
+    auto peer = winrt::FrameworkElementAutomationPeer::FromElement(element);
+    if (nullptr != peer)
+    {
+      peer.RaiseAutomationEvent(winrt::AutomationEvents::LiveRegionChanged);
+    }
+  }
+}
+
 } }

vnext/include/ReactUWP/Views/FrameworkElementViewManager.h

@@ -20,6 +20,8 @@ class REACTWINDOWS_EXPORT FrameworkElementViewManager : public ViewManagerBase
   virtual void TransferProperties(XamlView oldView, XamlView newView) override;
 
   void TransferProperty(XamlView oldView, XamlView newView, winrt::Windows::UI::Xaml::DependencyProperty dp);
+
+  void AnnounceIfNeeded(winrt::FrameworkElement element);
 };
 
 } }

vnext/src/RNTester/AccessibilityExample.tsx

@@ -46,7 +46,7 @@ class TouchableExamples extends React.Component<{}, any> {
         >
           <Text>Blue</Text>
         </TouchableHighlight>
-        <Text>Pressed {this.state.pressedCount} times</Text>
+        <Text accessibilityLiveRegion="polite">Pressed {this.state.pressedCount} times</Text>
       </View>
     );
   }