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/* clang-format off */
/* -*- Mode: Objective-C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* clang-format on */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#import "MUIAccessible.h"
#include "nsString.h"
#include "RootAccessibleWrap.h"
using namespace mozilla;
using namespace mozilla::a11y;
#ifdef A11Y_LOG
# define DEBUG_HINTS
#endif
#ifdef DEBUG_HINTS
static NSString* ToNSString(const nsACString& aCString) {
if (aCString.IsEmpty()) {
return [NSString string];
}
return [[[NSString alloc] initWithBytes:aCString.BeginReading()
length:aCString.Length()
encoding:NSUTF8StringEncoding] autorelease];
}
#endif
static NSString* ToNSString(const nsAString& aString) {
if (aString.IsEmpty()) {
return [NSString string];
}
return [NSString stringWithCharacters:reinterpret_cast<const unichar*>(
aString.BeginReading())
length:aString.Length()];
}
// These rules offer conditions for whether a gecko accessible
// should be considered a UIKit accessibility element. Each role is mapped to a
// rule.
enum class IsAccessibilityElementRule {
// Always yes
Yes,
// Always no
No,
// If the accessible has no children. For example an empty header
// which is labeled.
IfChildless,
// If the accessible has no children and it is named and focusable.
IfChildlessWithNameAndFocusable,
// If this accessible isn't a child of an accessibility element. For example,
// a text leaf child of a button.
IfParentIsntElementWithName,
// If this accessible has multiple leafs that should functionally be
// united, for example a link with span elements.
IfBrokenUp,
};
class Trait {
public:
static const uint64_t None = 0;
static const uint64_t Button = ((uint64_t)0x1) << 0;
static const uint64_t Link = ((uint64_t)0x1) << 1;
static const uint64_t Image = ((uint64_t)0x1) << 2;
static const uint64_t Selected = ((uint64_t)0x1) << 3;
static const uint64_t PlaysSound = ((uint64_t)0x1) << 4;
static const uint64_t KeyboardKey = ((uint64_t)0x1) << 5;
static const uint64_t StaticText = ((uint64_t)0x1) << 6;
static const uint64_t SummaryElement = ((uint64_t)0x1) << 7;
static const uint64_t NotEnabled = ((uint64_t)0x1) << 8;
static const uint64_t UpdatesFrequently = ((uint64_t)0x1) << 9;
static const uint64_t SearchField = ((uint64_t)0x1) << 10;
static const uint64_t StartsMediaSession = ((uint64_t)0x1) << 11;
static const uint64_t Adjustable = ((uint64_t)0x1) << 12;
static const uint64_t AllowsDirectInteraction = ((uint64_t)0x1) << 13;
static const uint64_t CausesPageTurn = ((uint64_t)0x1) << 14;
static const uint64_t TabBar = ((uint64_t)0x1) << 15;
static const uint64_t Header = ((uint64_t)0x1) << 16;
static const uint64_t WebContent = ((uint64_t)0x1) << 17;
static const uint64_t TextEntry = ((uint64_t)0x1) << 18;
static const uint64_t PickerElement = ((uint64_t)0x1) << 19;
static const uint64_t RadioButton = ((uint64_t)0x1) << 20;
static const uint64_t IsEditing = ((uint64_t)0x1) << 21;
static const uint64_t LaunchIcon = ((uint64_t)0x1) << 22;
static const uint64_t StatusBarElement = ((uint64_t)0x1) << 23;
static const uint64_t SecureTextField = ((uint64_t)0x1) << 24;
static const uint64_t Inactive = ((uint64_t)0x1) << 25;
static const uint64_t Footer = ((uint64_t)0x1) << 26;
static const uint64_t BackButton = ((uint64_t)0x1) << 27;
static const uint64_t TabButton = ((uint64_t)0x1) << 28;
static const uint64_t AutoCorrectCandidate = ((uint64_t)0x1) << 29;
static const uint64_t DeleteKey = ((uint64_t)0x1) << 30;
static const uint64_t SelectionDismissesItem = ((uint64_t)0x1) << 31;
static const uint64_t Visited = ((uint64_t)0x1) << 32;
static const uint64_t Scrollable = ((uint64_t)0x1) << 33;
static const uint64_t Spacer = ((uint64_t)0x1) << 34;
static const uint64_t TableIndex = ((uint64_t)0x1) << 35;
static const uint64_t Map = ((uint64_t)0x1) << 36;
static const uint64_t TextOperationsAvailable = ((uint64_t)0x1) << 37;
static const uint64_t Draggable = ((uint64_t)0x1) << 38;
static const uint64_t GesturePracticeRegion = ((uint64_t)0x1) << 39;
static const uint64_t PopupButton = ((uint64_t)0x1) << 40;
static const uint64_t AllowsNativeSliding = ((uint64_t)0x1) << 41;
static const uint64_t MathEquation = ((uint64_t)0x1) << 42;
static const uint64_t ContainedByTable = ((uint64_t)0x1) << 43;
static const uint64_t ContainedByList = ((uint64_t)0x1) << 44;
static const uint64_t TouchContainer = ((uint64_t)0x1) << 45;
static const uint64_t SupportsZoom = ((uint64_t)0x1) << 46;
static const uint64_t TextArea = ((uint64_t)0x1) << 47;
static const uint64_t BookContent = ((uint64_t)0x1) << 48;
static const uint64_t ContainedByLandmark = ((uint64_t)0x1) << 49;
static const uint64_t FolderIcon = ((uint64_t)0x1) << 50;
static const uint64_t ReadOnly = ((uint64_t)0x1) << 51;
static const uint64_t MenuItem = ((uint64_t)0x1) << 52;
static const uint64_t Toggle = ((uint64_t)0x1) << 53;
static const uint64_t IgnoreItemChooser = ((uint64_t)0x1) << 54;
static const uint64_t SupportsTrackingDetail = ((uint64_t)0x1) << 55;
static const uint64_t Alert = ((uint64_t)0x1) << 56;
static const uint64_t ContainedByFieldset = ((uint64_t)0x1) << 57;
static const uint64_t AllowsLayoutChangeInStatusBar = ((uint64_t)0x1) << 58;
};
#pragma mark -
@interface NSObject (AccessibilityPrivate)
- (void)_accessibilityUnregister;
@end
@implementation MUIAccessible
- (id)initWithAccessible:(Accessible*)aAcc {
MOZ_ASSERT(aAcc, "Cannot init MUIAccessible with null");
if ((self = [super init])) {
mGeckoAccessible = aAcc;
}
return self;
}
- (mozilla::a11y::Accessible*)geckoAccessible {
return mGeckoAccessible;
}
- (void)expire {
mGeckoAccessible = nullptr;
if ([self respondsToSelector:@selector(_accessibilityUnregister)]) {
[self _accessibilityUnregister];
}
}
- (void)dealloc {
[super dealloc];
}
static bool isAccessibilityElementInternal(Accessible* aAccessible) {
MOZ_ASSERT(aAccessible);
IsAccessibilityElementRule rule = IsAccessibilityElementRule::No;
#define ROLE(_geckoRole, stringRole, ariaRole, atkRole, macRole, macSubrole, \
msaaRole, ia2Role, androidClass, iosIsElement, uiaControlType, \
nameRule) \
case roles::_geckoRole: \
rule = iosIsElement; \
break;
switch (aAccessible->Role()) {
#include "RoleMap.h"
}
switch (rule) {
case IsAccessibilityElementRule::Yes:
return true;
case IsAccessibilityElementRule::No:
return false;
case IsAccessibilityElementRule::IfChildless:
return aAccessible->ChildCount() == 0;
case IsAccessibilityElementRule::IfParentIsntElementWithName: {
nsAutoString name;
aAccessible->Name(name);
name.CompressWhitespace();
if (name.IsEmpty()) {
return false;
}
if (isAccessibilityElementInternal(aAccessible->Parent())) {
// This is a text leaf that needs to be pruned from a button or the
// likes. It should also be ignored in the event of its parent being a
// pruned link.
return false;
}
return true;
}
case IsAccessibilityElementRule::IfChildlessWithNameAndFocusable:
if (aAccessible->ChildCount() == 0 &&
(aAccessible->State() & states::FOCUSABLE)) {
nsAutoString name;
aAccessible->Name(name);
name.CompressWhitespace();
return !name.IsEmpty();
}
return false;
case IsAccessibilityElementRule::IfBrokenUp: {
uint32_t childCount = aAccessible->ChildCount();
if (childCount == 1) {
// If this is a single child container just use the text leaf and its
// traits will be inherited.
return false;
}
for (uint32_t idx = 0; idx < childCount; idx++) {
Accessible* child = aAccessible->ChildAt(idx);
role accRole = child->Role();
if (accRole != roles::STATICTEXT && accRole != roles::TEXT_LEAF &&
accRole != roles::GRAPHIC) {
// If this container contains anything but text leafs and images
// ignore this accessible. Its descendants will inherit the
// container's traits.
return false;
}
}
return true;
}
default:
break;
}
MOZ_ASSERT_UNREACHABLE("Unhandled IsAccessibilityElementRule");
return false;
}
- (BOOL)isAccessibilityElement {
if (!mGeckoAccessible) {
return NO;
}
return isAccessibilityElementInternal(mGeckoAccessible) ? YES : NO;
}
- (NSString*)accessibilityLabel {
if (!mGeckoAccessible) {
return @"";
}
nsAutoString name;
mGeckoAccessible->Name(name);
return ToNSString(name);
}
- (NSString*)accessibilityHint {
if (!mGeckoAccessible) {
return @"";
}
#ifdef DEBUG_HINTS
// Just put in a debug description as the label so we get a clue about which
// accessible ends up where.
nsAutoCString desc;
mGeckoAccessible->DebugDescription(desc);
return ToNSString(desc);
#else
return @"";
#endif
}
- (CGRect)accessibilityFrame {
RootAccessibleWrap* rootAcc = static_cast<RootAccessibleWrap*>(
mGeckoAccessible->IsLocal()
? mGeckoAccessible->AsLocal()->RootAccessible()
: mGeckoAccessible->AsRemote()
->OuterDocOfRemoteBrowser()
->RootAccessible());
if (!rootAcc) {
return CGRectMake(0, 0, 0, 0);
}
LayoutDeviceIntRect rect = mGeckoAccessible->Bounds();
return rootAcc->DevPixelsRectToUIKit(rect);
}
- (NSString*)accessibilityValue {
if (!mGeckoAccessible) {
return nil;
}
uint64_t state = mGeckoAccessible->State();
if (state & states::LINKED) {
// Value returns the URL. We don't want to expose that as the value on iOS.
return nil;
}
if (state & states::CHECKABLE) {
if (state & states::CHECKED) {
return @"1";
}
if (state & states::MIXED) {
return @"2";
}
return @"0";
}
if (mGeckoAccessible->IsPassword()) {
// Accessible::Value returns an empty string. On iOS, we need to return the
// masked password so that AT knows how many characters are in the password.
Accessible* leaf = mGeckoAccessible->FirstChild();
if (!leaf) {
return nil;
}
nsAutoString masked;
leaf->AppendTextTo(masked);
return ToNSString(masked);
}
// If there is a heading ancestor, self has the header trait, so value should
// be the heading level.
for (Accessible* acc = mGeckoAccessible; acc; acc = acc->Parent()) {
if (acc->Role() == roles::HEADING) {
return [NSString stringWithFormat:@"%d", acc->GroupPosition().level];
}
}
nsAutoString value;
mGeckoAccessible->Value(value);
return ToNSString(value);
}
static uint64_t GetAccessibilityTraits(Accessible* aAccessible) {
uint64_t state = aAccessible->State();
uint64_t traits = Trait::WebContent;
switch (aAccessible->Role()) {
case roles::LINK:
traits |= Trait::Link;
break;
case roles::GRAPHIC:
traits |= Trait::Image;
break;
case roles::PAGETAB:
traits |= Trait::TabButton;
break;
case roles::PUSHBUTTON:
case roles::SUMMARY:
case roles::COMBOBOX:
case roles::BUTTONMENU:
case roles::TOGGLE_BUTTON:
case roles::CHECKBUTTON:
case roles::SWITCH:
traits |= Trait::Button;
break;
case roles::RADIOBUTTON:
traits |= Trait::RadioButton;
break;
case roles::HEADING:
traits |= Trait::Header;
break;
case roles::STATICTEXT:
case roles::TEXT_LEAF:
traits |= Trait::StaticText;
break;
case roles::SLIDER:
case roles::SPINBUTTON:
traits |= Trait::Adjustable;
break;
case roles::MENUITEM:
case roles::PARENT_MENUITEM:
case roles::CHECK_MENU_ITEM:
case roles::RADIO_MENU_ITEM:
traits |= Trait::MenuItem;
break;
case roles::PASSWORD_TEXT:
traits |= Trait::SecureTextField;
break;
default:
break;
}
if ((traits & Trait::Link) && (state & states::TRAVERSED)) {
traits |= Trait::Visited;
}
if ((traits & Trait::Button) && (state & states::HASPOPUP)) {
traits |= Trait::PopupButton;
}
if (state & states::SELECTED) {
traits |= Trait::Selected;
}
if (state & states::CHECKABLE) {
traits |= Trait::Toggle;
}
if (!(state & states::ENABLED)) {
traits |= Trait::NotEnabled;
}
if (state & states::EDITABLE) {
traits |= Trait::TextEntry;
if (state & states::FOCUSED) {
// XXX: Also add "has text cursor" trait
traits |= Trait::IsEditing | Trait::TextOperationsAvailable;
}
if (aAccessible->IsSearchbox()) {
traits |= Trait::SearchField;
}
if (state & states::MULTI_LINE) {
traits |= Trait::TextArea;
}
}
return traits;
}
- (uint64_t)accessibilityTraits {
if (!mGeckoAccessible) {
return Trait::None;
}
uint64_t traits = GetAccessibilityTraits(mGeckoAccessible);
for (Accessible* parent = mGeckoAccessible->Parent(); parent;
parent = parent->Parent()) {
traits |= GetAccessibilityTraits(parent);
}
return traits;
}
- (NSInteger)accessibilityElementCount {
return mGeckoAccessible ? mGeckoAccessible->ChildCount() : 0;
}
- (nullable id)accessibilityElementAtIndex:(NSInteger)index {
if (!mGeckoAccessible) {
return nil;
}
Accessible* child = mGeckoAccessible->ChildAt(index);
return GetNativeFromGeckoAccessible(child);
}
- (NSInteger)indexOfAccessibilityElement:(id)element {
Accessible* acc = [(MUIAccessible*)element geckoAccessible];
if (!acc || mGeckoAccessible != acc->Parent()) {
return -1;
}
return acc->IndexInParent();
}
- (NSArray* _Nullable)accessibilityElements {
NSMutableArray* children = [[[NSMutableArray alloc] init] autorelease];
uint32_t childCount = mGeckoAccessible->ChildCount();
for (uint32_t i = 0; i < childCount; i++) {
if (MUIAccessible* child =
GetNativeFromGeckoAccessible(mGeckoAccessible->ChildAt(i))) {
[children addObject:child];
}
}
return children;
}
- (UIAccessibilityContainerType)accessibilityContainerType {
return UIAccessibilityContainerTypeNone;
}
- (NSRange)_accessibilitySelectedTextRange {
if (!mGeckoAccessible || !mGeckoAccessible->IsHyperText()) {
return NSMakeRange(NSNotFound, 0);
}
// XXX This will only work in simple plain text boxes. It will break horribly
// if there are any embedded objects. Also, it only supports caret, not
// selection.
int32_t caret = mGeckoAccessible->AsHyperTextBase()->CaretOffset();
if (caret != -1) {
return NSMakeRange(caret, 0);
}
return NSMakeRange(NSNotFound, 0);
}
- (void)_accessibilitySetSelectedTextRange:(NSRange)range {
if (!mGeckoAccessible || !mGeckoAccessible->IsHyperText()) {
return;
}
// XXX This will only work in simple plain text boxes. It will break horribly
// if there are any embedded objects. Also, it only supports caret, not
// selection.
mGeckoAccessible->AsHyperTextBase()->SetCaretOffset(range.location);
}
@end