Bug 285711. Support accessible alerts. r=pkwarren, sr=henry.jia

accessible/public/nsIAccessibilityService.idl

@@ -51,11 +51,12 @@ interface nsIAccessibilityService : nsIAccessibleRetrieval
   nsIAccessible createRootAccessible(in nsIPresShell aShell, in nsIDocument aDocument);
 
   nsIAccessible createHTML4ButtonAccessible(in nsISupports aFrame);
+  nsIAccessible createXULAlertAccessible(in nsIDOMNode aNode);
   nsIAccessible createHTMLAreaAccessible(in nsIWeakReference aPresShell, in nsIDOMNode aDOMNode, in nsIAccessible aAccParent);
   nsIAccessible createHTMLBlockAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLButtonAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLButtonAccessibleXBL(in nsIDOMNode aNode);
-  nsIAccessible createHTMLAccessibleByMarkup(in nsISupports aFrame);
+  nsIAccessible createHTMLAccessibleByMarkup(in nsISupports aFrame, in nsIWeakReference aWeakShell, in nsIDOMNode aDOMNode);
   nsIAccessible createHTMLLIAccessible(in nsISupports aFrame, in nsISupports aBulletFrame, in AString aBulletText);
   nsIAccessible createHTMLCheckboxAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLCheckboxAccessibleXBL(in nsIDOMNode aNode);

accessible/src/base/nsAccessibilityService.cpp

@@ -76,6 +76,7 @@
 #include "nsPIAccessNode.h"
 
 #ifdef MOZ_XUL
+#include "nsXULAlertAccessible.h"
 #include "nsXULColorPickerAccessible.h"
 #include "nsXULFormControlAccessible.h"
 #include "nsXULMenuAccessible.h"
@@ -419,33 +420,28 @@ nsAccessibilityService::CreateHTMLButtonAccessibleXBL(nsIDOMNode *aNode, nsIAcce
 
 NS_IMETHODIMP
 nsAccessibilityService::CreateHTMLAccessibleByMarkup(nsISupports *aFrame,
+                                                     nsIWeakReference *aWeakShell,
+                                                     nsIDOMNode *aNode,
                                                      nsIAccessible **aAccessible)
 {
-  // Frame type was generic, we'll use the DOM to decide 
+  // aFrame type was generic, we'll use the DOM to decide 
   // if and what kind of accessible object is needed.
   // This method assumes we're in an HTML namespace.
   *aAccessible = nsnull;
-  nsIFrame* frame;
-  nsCOMPtr<nsIDOMNode> node;
-  nsCOMPtr<nsIWeakReference> weakShell;
-  nsresult rv = GetInfo(aFrame, &frame, getter_AddRefs(weakShell), getter_AddRefs(node));
-  NS_ENSURE_SUCCESS(rv, rv);
-  nsIContent *content = frame->GetContent();
-  NS_ENSURE_TRUE(content, NS_ERROR_FAILURE);
-
+  nsCOMPtr<nsIContent> content(do_QueryInterface(aNode));
   nsIAtom *tag = content->Tag();
   if (tag == nsAccessibilityAtoms::option) {
-    *aAccessible = new nsHTMLSelectOptionAccessible(node, weakShell);
+    *aAccessible = new nsHTMLSelectOptionAccessible(aNode, aWeakShell);
   }
   else if (tag == nsAccessibilityAtoms::optgroup) {
-    *aAccessible = new nsHTMLSelectOptGroupAccessible(node, weakShell);
+    *aAccessible = new nsHTMLSelectOptGroupAccessible(aNode, aWeakShell);
   }
 #ifndef MOZ_ACCESSIBILITY_ATK
   else if (tag == nsAccessibilityAtoms::ul || tag == nsAccessibilityAtoms::ol) {
-    *aAccessible = new nsHTMLListAccessible(node, weakShell);
+    *aAccessible = new nsHTMLListAccessible(aNode, aWeakShell);
   }
   else if (tag == nsAccessibilityAtoms::a) {
-    *aAccessible = new nsHTMLLinkAccessible(node, weakShell, frame);
+    *aAccessible = new nsHTMLLinkAccessible(aNode, aWeakShell, NS_STATIC_CAST(nsIFrame*, aFrame));
   }
 #endif
   else if (content->HasAttr(kNameSpaceID_None, nsAccessibilityAtoms::tabindex) ||
@@ -463,7 +459,7 @@ nsAccessibilityService::CreateHTMLAccessibleByMarkup(nsISupports *aFrame,
            tag == nsAccessibilityAtoms::q
 #endif
            ) {
-    *aAccessible = new nsAccessibleWrap(node, weakShell);
+    *aAccessible = new nsAccessibleWrap(aNode, aWeakShell);
   }
   NS_IF_ADDREF(*aAccessible);
   return NS_OK;
@@ -1230,6 +1226,24 @@ nsAccessibilityService::CreateXULMenuSeparatorAccessible(nsIDOMNode *aNode, nsIA
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsAccessibilityService::CreateXULAlertAccessible(nsIDOMNode *aNode, nsIAccessible **aAccessible)
+{
+#ifdef MOZ_XUL
+  nsCOMPtr<nsIWeakReference> weakShell;
+  GetShellFromNode(aNode, getter_AddRefs(weakShell));
+
+  *aAccessible = new nsXULAlertAccessible(aNode, weakShell);
+  if (! *aAccessible)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  NS_ADDREF(*aAccessible);
+#else
+  *_retval = nsnull;
+#endif
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsAccessibilityService::CreateXULProgressMeterAccessible(nsIDOMNode *aNode, nsIAccessible **_retval)
 {
@@ -1793,7 +1807,7 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
     if (!newAcc) {
       // Use markup (mostly tag name, perhaps attributes) to
       // decide if and what kind of accessible to create.
-      CreateHTMLAccessibleByMarkup(frame, getter_AddRefs(newAcc));
+      CreateHTMLAccessibleByMarkup(frame, aWeakShell, aNode, getter_AddRefs(newAcc));
     }
   }
 

accessible/src/base/nsAccessible.cpp

@@ -1348,6 +1348,7 @@ nsRoleMapEntry nsAccessible::gWAIRoleMap[] =
   // Using RDF will also allow for role extensibility.
   // XXX Should we store attribute names in this table as atoms instead of strings?
   // Definition of nsRoleMapEntry and nsStateMapEntry contains comments explaining this table.
+  {"alert", ROLE_ALERT, eAggregateSubtree, 0, {0, 0, 0}, {0, 0, 0}, {0, 0, 0}},
   {"button", ROLE_PUSHBUTTON, eAggregateSubtree, 0, {0, 0, 0}, {0, 0, 0}, {0, 0, 0}},
   {"checkbox", ROLE_CHECKBUTTON, eAggregateSubtree, 0, {"checked", "true", STATE_CHECKED}, {"readonly", 0, STATE_READONLY}, {0, 0, 0}},
   {"checkbox-tristate", ROLE_CHECKBUTTON, eAggregateSubtree, 0, {"checked", "true", STATE_CHECKED}, {"checked", "mixed", STATE_MIXED}, {"readonly", 0, STATE_READONLY}},

accessible/src/base/nsRootAccessible.cpp

@@ -232,6 +232,10 @@ nsresult nsRootAccessible::AddEventListeners()
     rv = target->AddEventListener(NS_LITERAL_STRING("ValueChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
     NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
 
+    // capture AlertActive events (fired whenever alert pops up)
+    rv = target->AddEventListener(NS_LITERAL_STRING("AlertActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
+    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
+
     // add ourself as a OpenStateChange listener (custom event fired in tree.xml)
     rv = target->AddEventListener(NS_LITERAL_STRING("OpenStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
     NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
@@ -288,6 +292,7 @@ nsresult nsRootAccessible::RemoveEventListeners()
     target->RemoveEventListener(NS_LITERAL_STRING("focus"), NS_STATIC_CAST(nsIDOMFocusListener*, this), PR_TRUE);
     target->RemoveEventListener(NS_LITERAL_STRING("select"), NS_STATIC_CAST(nsIDOMFormListener*, this), PR_TRUE);
     target->RemoveEventListener(NS_LITERAL_STRING("ValueChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
+    target->RemoveEventListener(NS_LITERAL_STRING("AlertActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
     target->RemoveEventListener(NS_LITERAL_STRING("OpenStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
     target->RemoveEventListener(NS_LITERAL_STRING("CheckboxStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
     target->RemoveEventListener(NS_LITERAL_STRING("RadioStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
@@ -674,6 +679,10 @@ NS_IMETHODIMP nsRootAccessible::HandleEvent(nsIDOMEvent* aEvent)
     privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_VALUE_CHANGE, 
                               accessible, nsnull);
   }
+  else if (eventType.EqualsLiteral("AlertActive")) { 
+    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_ALERT, 
+                              accessible, nsnull);
+  }
   else if (eventType.LowerCaseEqualsLiteral("checkboxstatechange") ||
            eventType.LowerCaseEqualsLiteral("openstatechange")) {
       privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, 

accessible/src/msaa/nsAccessibleWrap.cpp

@@ -237,8 +237,9 @@ STDMETHODIMP nsAccessibleWrap::get_accName(
     nsAutoString name;
     if (NS_FAILED(xpAccessible->GetName(name)))
       return S_FALSE;
-
-    *pszName = ::SysAllocString(name.get());
+    if (!name.IsVoid()) {
+      *pszName = ::SysAllocString(name.get());
+    }
     NS_ASSERTION(mIsInitialized, "Access node was not initialized");
   }
 

accessible/src/xul/Makefile.in

@@ -65,6 +65,7 @@ REQUIRES += editor
 endif
 
 CPPSRCS = \
+  nsXULAlertAccessible.cpp \
   nsXULColorPickerAccessible.cpp \
   nsXULFormControlAccessible.cpp \
   nsXULMenuAccessible.cpp \

toolkit/content/widgets/tabbrowser.xml

@@ -227,6 +227,10 @@
             message.docShell = aDocShell;
             message.closeButton = aShowCloseButton;
             aBrowser.isShowingMessage = true;
+            // Fire event for accessibility APIs
+            var event = document.createEvent("Events");
+            event.initEvent("AlertActive", true, true);
+            message.dispatchEvent(event);
           ]]>
         </body>
       </method>