We previously cached aria-placeholder, but not HTML placeholder.
These both map to the placeholder object attribute exposed by Accessible::Attributes, but they are retrieved differently internally.
This also fixes LocalAccessible::Attributes to always prefer HTML placeholder over aria-placeholder as per the ARIA spec.
Previously, the attribute we preferred was somewhat indeterminate (from the user's perspective) due to the ordering of hash maps.
Differential Revision: https://phabricator.services.mozilla.com/D184795
This only worked with the COM proxy architecture.
It cannot be used with the cache active.
This includes ScrollSubstringToPoint, and since that isn't currently supported by the cache, it isn't supported at all on Windows now.
However, no one seems to use this on Windows and this implementation can't be used with the cache active anyway.
Differential Revision: https://phabricator.services.mozilla.com/D177901
This is used by the Web Access NVDA add-on to identify and remediate some inaccessible elements on websites with accessibility problems.
It is also useful for developers using screen readers when trying to identify specific elements in the absence of semantics.
Differential Revision: https://phabricator.services.mozilla.com/D176896
When hit testing, we retrieve the bounds for every character in a text leaf in a separate call.
Because we need to convert from an array of flat ints to rects, this previously meant we built the entire array for every character.
For a large text leaf, building this rect array is relatively expensive.
We only need a single rect at a time.
Therefore, RemoteAccessibleBase now returns the rect for a single requested character instead of building an array of rects.
Differential Revision: https://phabricator.services.mozilla.com/D171419
We'd like to provide NODE_CHILD_OF and NODE_PARENT_OF relations in the parent
process, relying on cached information, to avoid sync IPDL messages. This
revision implements most of the use cases for this relation for remote
accessibles, notably setting aside handling of MathML's <mroot> parent/child
relation. ARIA trees, treegrids, lists, and so on are handled in the remote
accessible largely identically to how they were handled in LocalAccessible.
Rather than define a new rule for walking the tree to find children, this
revision unifies the ItemIterator so it works on generic Accessibles, and uses
it in RemoteAccessibleBase the same way it's used in LocalAccessible. The
special case carve-out for MSAA clients now exists as a simpler IsTopLevel
check in DocAccessibleParent.
Differential Revision: https://phabricator.services.mozilla.com/D159452
Windows a11y clients retrieve MathML markup using ISimpleDOMNode::innerHTML.
We cache innerHTML to support this, but only on math elements and only on Windows.
sdnAccessible had to be modified to support RemoteAccessible and to use the cache for this method.
Differential Revision: https://phabricator.services.mozilla.com/D155806
This hittesting approach is borrowed from our Android implementation.
We maintain a cache of ID's for accessibles which are visible in the viewport.
This cache is created with a call to `nsLayoutUtils::GetFramesForArea`, which
returns frames in the viewport, in hittesting order.
In the parent process, we walk through the cache, keeping track of accs whose
bounds contain the hittesting point. Depending on if we're searching for the
direct child, or the deepest child, we walk the entire cache or return the
first match.
Each document (in the content process) maintains a dirty bit, which gets set
any time an acc it contains bundles either a text update, or an update that
affects bounds. We check whether this bit is set in `DidRefresh` after getting
a notification from our post-refresh observer. If that bit is set, we
queue a cache update for the `::Viewport` domain on the current document.
Because this cache depends on the viewport being painted, we include the
`IgnorePaintSuppression` flag in our `GetFramesForArea` call. This ensures
the display lists are built before the page finishes loading.
Differential Revision: https://phabricator.services.mozilla.com/D147225
This hittesting approach is borrowed from our Android implementation.
We maintain a cache of ID's for accessibles which are visible in the viewport.
This cache is created with a call to `nsLayoutUtils::GetFramesForArea`, which
returns frames in the viewport, in hittesting order.
In the parent process, we walk through the cache, keeping track of accs whose
bounds contain the hittesting point. Depending on if we're searching for the
direct child, or the deepest child, we walk the entire cache or return the
first match.
Each document (in the content process) maintains a dirty bit, which gets set
any time an acc it contains bundles either a text update, or an update that
affects bounds. We check whether this bit is set in `DidRefresh` after getting
a notification from our post-refresh observer. If that bit is set, we
queue a cache update for the `::Viewport` domain on the current document.
Because this cache depends on the viewport being painted, we include the
`IgnorePaintSuppression` flag in our `GetFramesForArea` call. This ensures
the display lists are built before the page finishes loading.
Differential Revision: https://phabricator.services.mozilla.com/D147225
Even though spelling errors can cross Accessibles and are represented in the DOM as ranges, we cache them for each text leaf.
This is necessary so that we correctly update the offsets when text is inserted or removed from a leaf.
We cache them as an array of offsets, including both the start and end offset for each range.
We use -1 as the start offset to indicate when a spelling error starts in a previous Accessible.
When a spelling error starts in an Accessible but ends in a subsequent one, we simply don't include an end offset in the array.
This structure means we can easily query spelling error points or ranges with a binary search.
Differential Revision: https://phabricator.services.mozilla.com/D147243
We detect this in the same way that we detect whether we need to push line starts; i.e. a text update or a bounds change.
Since this is tied to the Text and Bounds domains, I removed the separate TextBounds domain.
Differential Revision: https://phabricator.services.mozilla.com/D147396
This also adds Accessible::DisplayStyle, as we sometimes want to be able to get the display style without fetching all the Attributes.
Differential Revision: https://phabricator.services.mozilla.com/D138629
