Bug 1888310: Verify a11y-announcement is a child of ChildView instead of mozRootAccessible r=eeejay

Previously we checked if the announcement was a child of the root acc directly, but it's not clear this worked reliably since we've done `GetObjectOrRepresentedView` for a while, which (should) return the view instead of the root acc. This patch also:
- Dispatches the announcement from NSApp instead of NSWindow, since per chrome and safari notifs fired on non-main windows get dropped
- Modifies the announcement priority from medium to high, so VO interrupts itself to speak this message (this makes the UX more consistent, since the text-inserted/text-deleted notifs from the URL bar seem to occasionally bookend the announcement)
- Updates the browser_app.js test to NOT run in headless mode, since in headless mode NSApp isn't rendered to dispatch the notification. This test contains a task for AXAnnouncementRequested via a11yUtils.announce

Differential Revision: https://phabricator.services.mozilla.com/D206083
This commit is contained in:
Morgan Rae Reschenberg 2024-06-04 20:42:45 +00:00
parent 6ffc34fe0a
commit 4e0ffe1a17

View file

@ -879,10 +879,13 @@ struct RoleDescrComparator {
// a random acc with the same ID) by checking:
// - The gecko acc is local, our a11y-announcement lives in browser.xhtml
// - The ID of the gecko acc is "a11y-announcement"
// - The native acc is a direct descendent of the root
// - The native acc is a direct descendent of the chrome window (ChildView in
// a non-headless context, mozRootAccessible in a headless context).
if (mGeckoAccessible->IsLocal() &&
[[self moxDOMIdentifier] isEqualToString:@"a11y-announcement"] &&
[[self moxParent] isKindOfClass:[mozRootAccessible class]]) {
((gfxPlatform::IsHeadless() &&
[[self moxParent] isKindOfClass:[mozRootAccessible class]]) ||
[[self moxParent] isKindOfClass:[ChildView class]])) {
// Our actual announcement should be stored as a child of the alert,
// so we verify a child exists, and then query that child below.
NSArray* children = [self moxChildren];
@ -896,23 +899,24 @@ struct RoleDescrComparator {
} else {
key = [announcement moxTitle];
}
NSDictionary* info = @{
NSAccessibilityAnnouncementKey : key ? key : @(""),
NSAccessibilityPriorityKey : @(NSAccessibilityPriorityMedium)
// High priority means VO will stop what it is currently speaking
// to speak our announcement.
NSAccessibilityPriorityKey : @(NSAccessibilityPriorityHigh)
};
id window = [self moxWindow];
// This sends events via nsIObserverService to be consumed by our
// mochitests. Normally we'd fire these events through moxPostNotification
// which takes care of this, but because the window we fetch above isn't
// derrived from MOXAccessibleBase, we do this (and post the notification)
// manually.
// which takes care of this, but because NSApp isn't derived
// from MOXAccessibleBase, we do this (and post the notification) manually.
// We used to fire this on the window, but per Chrome and Safari these
// notifs get dropped if fired on any non-main window. We now fire on NSApp
// to avoid this.
xpcAccessibleMacEvent::FireEvent(
window, NSAccessibilityAnnouncementRequestedNotification, info);
NSApp, NSAccessibilityAnnouncementRequestedNotification, info);
NSAccessibilityPostNotificationWithUserInfo(
window, NSAccessibilityAnnouncementRequestedNotification, info);
NSApp, NSAccessibilityAnnouncementRequestedNotification, info);
}
}