Incubates #8045

source/NVDAObjects/UIA/__init__.py

@@ -31,6 +31,7 @@
 from NVDAObjects.behaviors import ProgressBar, EditableTextWithoutAutoSelectDetection, Dialog, Notification, EditableTextWithSuggestions
 import braille
 import time
+import ui
 
 class UIATextInfo(textInfos.TextInfo):
 
@@ -1391,6 +1392,16 @@ def event_UIA_systemAlert(self):
 		# Ideally, we wouldn't use getBrailleTextForProperties directly.
 		braille.handler.message(braille.getBrailleTextForProperties(name=self.name, role=self.role))
 
+	def event_UIA_notification(self, notificationKind=None, notificationProcessing=None, displayString=None, activityId=None):
+		"""
+		Introduced in Windows 10 Fall Creators Update (build 16299).
+		This base implementation announces all notifications from the UIA element.
+		Unlike other events, the text to be announced is not the name of the object, and parameters control how the incoming notification should be processed.
+		Subclasses can override this event and can react to notification processing instructions.
+		"""
+		if displayString:
+			ui.message(displayString)
+
 class TreeviewItem(UIA):
 
 	def _get_value(self):

source/_UIAHandler.py

@@ -154,7 +154,7 @@
 }
 
 class UIAHandler(COMObject):
-	_com_interfaces_=[IUIAutomationEventHandler,IUIAutomationFocusChangedEventHandler,IUIAutomationPropertyChangedEventHandler]
+	_com_interfaces_=[IUIAutomationEventHandler,IUIAutomationFocusChangedEventHandler,IUIAutomationPropertyChangedEventHandler,IUIAutomationNotificationEventHandler]
 
 	def __init__(self):
 		super(UIAHandler,self).__init__()
@@ -187,10 +187,13 @@ def MTAThreadFunc(self):
 			except (COMError,WindowsError,NameError):
 				self.clientObject=CoCreateInstance(CUIAutomation._reg_clsid_,interface=IUIAutomation,clsctx=CLSCTX_INPROC_SERVER)
 			if isUIA8:
-				try:
-					self.clientObject=self.clientObject.QueryInterface(IUIAutomation3)
-				except COMError:
-					self.clientObject=self.clientObject.QueryInterface(IUIAutomation2)
+				# #8009: use appropriate interface based on highest supported interface.
+				for interface in (IUIAutomation5, IUIAutomation4, IUIAutomation3, IUIAutomation2):
+					try:
+						self.clientObject=self.clientObject.QueryInterface(interface)
+						break
+					except COMError:
+						pass
 			log.info("UIAutomation: %s"%self.clientObject.__class__.__mro__[1].__name__)
 			self.windowTreeWalker=self.clientObject.createTreeWalker(self.clientObject.CreateNotCondition(self.clientObject.CreatePropertyCondition(UIA_NativeWindowHandlePropertyId,0)))
 			self.windowCacheRequest=self.clientObject.CreateCacheRequest()
@@ -211,6 +214,9 @@ def MTAThreadFunc(self):
 			self.clientObject.AddPropertyChangedEventHandler(self.rootElement,TreeScope_Subtree,self.baseCacheRequest,self,UIAPropertyIdsToNVDAEventNames.keys())
 			for x in UIAEventIdsToNVDAEventNames.iterkeys():  
 				self.clientObject.addAutomationEventHandler(x,self.rootElement,TreeScope_Subtree,self.baseCacheRequest,self)
+			# #7984: add support for notification event (IUIAutomation5, part of Windows 10 build 16299 and later).
+			if isinstance(self.clientObject, IUIAutomation5):
+				self.clientObject.AddNotificationEventHandler(self.rootElement,TreeScope_Subtree,self.baseCacheRequest,self)
 		except Exception as e:
 			self.MTAThreadInitException=e
 		finally:
@@ -293,6 +299,14 @@ def IUIAutomationPropertyChangedEventHandler_HandlePropertyChangedEvent(self,sen
 			obj=focus
 		eventHandler.queueEvent(NVDAEventName,obj)
 
+	def IUIAutomationNotificationEventHandler_HandleNotificationEvent(self,sender,NotificationKind,NotificationProcessing,displayString,activityId):
+		if not self.MTAThreadInitEvent.isSet():
+			# UIAHandler hasn't finished initialising yet, so just ignore this event.
+			return
+		import NVDAObjects.UIA
+		obj=NVDAObjects.UIA.UIA(UIAElement=sender)
+		eventHandler.queueEvent("UIA_notification",obj, notificationKind=NotificationKind, notificationProcessing=NotificationProcessing, displayString=displayString, activityId=activityId)
+
 	def _isUIAWindowHelper(self,hwnd):
 		# UIA in NVDA's process freezes in Windows 7 and below
 		processID=winUser.getWindowThreadProcessID(hwnd)[0]