[Security Solution][Detection Engine][A11y] Add Announcement for Exported Exception List

x-pack/solutions/security/plugins/security_solution/public/exceptions/pages/shared_lists/index.tsx

@@ -19,6 +19,7 @@ import {
   EuiPageHeader,
   EuiPagination,
   EuiPopover,
+  EuiScreenReaderLive,
   EuiSpacer,
   EuiText,
 } from '@elastic/eui';
@@ -162,6 +163,7 @@ export const SharedLists = React.memo(() => {
 
   const [exportDownload, setExportDownload] = useState<{ name?: string; blob?: Blob }>({});
   const [displayImportListFlyout, setDisplayImportListFlyout] = useState(false);
+  const [screenReaderMessage, setScreenReaderMessage] = useState('');
   const { addError, addSuccess } = useAppToasts();
 
   // Loading states
@@ -216,7 +218,18 @@ export const SharedLists = React.memo(() => {
   const handleExportSuccess = useCallback(
     (listId: string, name: string) =>
       (blob: Blob): void => {
-        addSuccess(i18n.EXCEPTION_LIST_EXPORTED_SUCCESSFULLY(name));
+        const message = i18n.EXCEPTION_LIST_EXPORTED_SUCCESSFULLY(name);
+        addSuccess(message);
+        // If the same list is exported twice in a row, React won't re-render
+        // since state hasn't changed, so the live region won't re-announce.
+        // Clearing to '' first ensures VoiceOver sees a new change on the next frame.
+        setScreenReaderMessage((current) => {
+          if (current === message) {
+            requestAnimationFrame(() => setScreenReaderMessage(message));
+            return '';
+          }
+          return message;
+        });
         setExportDownload({ name: listId, blob });
       },
     [addSuccess]
@@ -480,6 +493,9 @@ export const SharedLists = React.memo(() => {
 
   return (
     <>
+      <EuiScreenReaderLive aria-live="assertive" aria-atomic="true" focusRegionOnTextChange>
+        {screenReaderMessage}
+      </EuiScreenReaderLive>
       <MissingDetectionsPrivilegesCallOut />
       <EuiPageHeader
         pageTitle={i18n.ALL_EXCEPTIONS}