MacViews: Accessibility bridge

ui/accessibility/platform/ax_platform_node_mac.mm

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ui/accessibility/platform/ax_platform_node_mac.h"
+
+#import <Cocoa/Cocoa.h>
+
+#include "base/strings/sys_string_conversions.h"
+#import "ui/accessibility/platform/ax_platform_node_delegate.h"
+#import "ui/gfx/mac/coordinate_conversion.h"
+
+namespace {
+
+struct MapEntry {
+  ui::AXRole value;
+  NSString* nativeValue;
+};
+
+typedef std::map<ui::AXRole, NSString*> RoleMap;
+
+RoleMap BuildRoleMap() {
+  const MapEntry roles[] = {
+      {ui::AX_ROLE_ALERT, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_ALERT_DIALOG, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_ANNOTATION, NSAccessibilityUnknownRole},
+      {ui::AX_ROLE_APPLICATION, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_ARTICLE, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_BANNER, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_BROWSER, NSAccessibilityBrowserRole},
+      {ui::AX_ROLE_BUSY_INDICATOR, NSAccessibilityBusyIndicatorRole},
+      {ui::AX_ROLE_BUTTON, NSAccessibilityButtonRole},
+      {ui::AX_ROLE_CANVAS, NSAccessibilityImageRole},
+      {ui::AX_ROLE_CELL, @"AXCell"},
+      {ui::AX_ROLE_CHECK_BOX, NSAccessibilityCheckBoxRole},
+      {ui::AX_ROLE_COLOR_WELL, NSAccessibilityColorWellRole},
+      {ui::AX_ROLE_COLUMN, NSAccessibilityColumnRole},
+      {ui::AX_ROLE_COLUMN_HEADER, @"AXCell"},
+      {ui::AX_ROLE_COMBO_BOX, NSAccessibilityComboBoxRole},
+      {ui::AX_ROLE_COMPLEMENTARY, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_CONTENT_INFO, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DEFINITION, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DESCRIPTION_LIST_DETAIL, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DESCRIPTION_LIST_TERM, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DIALOG, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DIRECTORY, NSAccessibilityListRole},
+      {ui::AX_ROLE_DISCLOSURE_TRIANGLE, NSAccessibilityDisclosureTriangleRole},
+      {ui::AX_ROLE_DIV, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DOCUMENT, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_DRAWER, NSAccessibilityDrawerRole},
+      {ui::AX_ROLE_EDITABLE_TEXT, NSAccessibilityTextFieldRole},
+      {ui::AX_ROLE_FOOTER, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_FORM, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_GRID, NSAccessibilityGridRole},
+      {ui::AX_ROLE_GROUP, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_GROW_AREA, NSAccessibilityGrowAreaRole},
+      {ui::AX_ROLE_HEADING, @"AXHeading"},
+      {ui::AX_ROLE_HELP_TAG, NSAccessibilityHelpTagRole},
+      {ui::AX_ROLE_HORIZONTAL_RULE, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_IFRAME, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_IGNORED, NSAccessibilityUnknownRole},
+      {ui::AX_ROLE_IMAGE, NSAccessibilityImageRole},
+      {ui::AX_ROLE_IMAGE_MAP, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_IMAGE_MAP_LINK, NSAccessibilityLinkRole},
+      {ui::AX_ROLE_INCREMENTOR, NSAccessibilityIncrementorRole},
+      {ui::AX_ROLE_LABEL_TEXT, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_LINK, NSAccessibilityLinkRole},
+      {ui::AX_ROLE_LIST, NSAccessibilityListRole},
+      {ui::AX_ROLE_LIST_BOX, NSAccessibilityListRole},
+      {ui::AX_ROLE_LIST_BOX_OPTION, NSAccessibilityStaticTextRole},
+      {ui::AX_ROLE_LIST_ITEM, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_LIST_MARKER, @"AXListMarker"},
+      {ui::AX_ROLE_LOG, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_MAIN, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_MARQUEE, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_MATH, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_MATTE, NSAccessibilityMatteRole},
+      {ui::AX_ROLE_MENU, NSAccessibilityMenuRole},
+      {ui::AX_ROLE_MENU_BAR, NSAccessibilityMenuBarRole},
+      {ui::AX_ROLE_MENU_BUTTON, NSAccessibilityButtonRole},
+      {ui::AX_ROLE_MENU_ITEM, NSAccessibilityMenuItemRole},
+      {ui::AX_ROLE_MENU_LIST_OPTION, NSAccessibilityMenuItemRole},
+      {ui::AX_ROLE_MENU_LIST_POPUP, NSAccessibilityUnknownRole},
+      {ui::AX_ROLE_NAVIGATION, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_NOTE, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_OUTLINE, NSAccessibilityOutlineRole},
+      {ui::AX_ROLE_PARAGRAPH, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_POP_UP_BUTTON, NSAccessibilityPopUpButtonRole},
+      {ui::AX_ROLE_PRESENTATIONAL, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_PROGRESS_INDICATOR, NSAccessibilityProgressIndicatorRole},
+      {ui::AX_ROLE_RADIO_BUTTON, NSAccessibilityRadioButtonRole},
+      {ui::AX_ROLE_RADIO_GROUP, NSAccessibilityRadioGroupRole},
+      {ui::AX_ROLE_REGION, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_ROOT_WEB_AREA, @"AXWebArea"},
+      {ui::AX_ROLE_ROW, NSAccessibilityRowRole},
+      {ui::AX_ROLE_ROW_HEADER, @"AXCell"},
+      {ui::AX_ROLE_RULER, NSAccessibilityRulerRole},
+      {ui::AX_ROLE_RULER_MARKER, NSAccessibilityRulerMarkerRole},
+      {ui::AX_ROLE_SCROLL_BAR, NSAccessibilityScrollBarRole},
+      {ui::AX_ROLE_SEARCH, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_SHEET, NSAccessibilitySheetRole},
+      {ui::AX_ROLE_SLIDER, NSAccessibilitySliderRole},
+      {ui::AX_ROLE_SLIDER_THUMB, NSAccessibilityValueIndicatorRole},
+      {ui::AX_ROLE_SPIN_BUTTON, NSAccessibilitySliderRole},
+      {ui::AX_ROLE_SPLITTER, NSAccessibilitySplitterRole},
+      {ui::AX_ROLE_SPLIT_GROUP, NSAccessibilitySplitGroupRole},
+      {ui::AX_ROLE_STATIC_TEXT, NSAccessibilityStaticTextRole},
+      {ui::AX_ROLE_STATUS, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_SVG_ROOT, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_SYSTEM_WIDE, NSAccessibilityUnknownRole},
+      {ui::AX_ROLE_TAB, NSAccessibilityRadioButtonRole},
+      {ui::AX_ROLE_TABLE, NSAccessibilityTableRole},
+      {ui::AX_ROLE_TABLE_HEADER_CONTAINER, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_TAB_LIST, NSAccessibilityTabGroupRole},
+      {ui::AX_ROLE_TAB_PANEL, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_TEXT_AREA, NSAccessibilityTextAreaRole},
+      {ui::AX_ROLE_TEXT_FIELD, NSAccessibilityTextFieldRole},
+      {ui::AX_ROLE_TIMER, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_TOGGLE_BUTTON, NSAccessibilityCheckBoxRole},
+      {ui::AX_ROLE_TOOLBAR, NSAccessibilityToolbarRole},
+      {ui::AX_ROLE_TOOLTIP, NSAccessibilityGroupRole},
+      {ui::AX_ROLE_TREE, NSAccessibilityOutlineRole},
+      {ui::AX_ROLE_TREE_GRID, NSAccessibilityTableRole},
+      {ui::AX_ROLE_TREE_ITEM, NSAccessibilityRowRole},
+      {ui::AX_ROLE_VALUE_INDICATOR, NSAccessibilityValueIndicatorRole},
+      {ui::AX_ROLE_WEB_AREA, @"AXWebArea"},
+      {ui::AX_ROLE_WINDOW, NSAccessibilityWindowRole},
+
+      // TODO(dtseng): we don't correctly support the attributes for these
+      // roles.
+      // { ui::AX_ROLE_SCROLL_AREA, NSAccessibilityScrollAreaRole },
+  };
+
+  RoleMap role_map;
+  for (size_t i = 0; i < arraysize(roles); ++i)
+    role_map[roles[i].value] = roles[i].nativeValue;
+  return role_map;
+}
+
+RoleMap BuildSubroleMap() {
+  const MapEntry subroles[] = {
+      {ui::AX_ROLE_ALERT, @"AXApplicationAlert"},
+      {ui::AX_ROLE_ALERT_DIALOG, @"AXApplicationAlertDialog"},
+      {ui::AX_ROLE_ARTICLE, @"AXDocumentArticle"},
+      {ui::AX_ROLE_DEFINITION, @"AXDefinition"},
+      {ui::AX_ROLE_DESCRIPTION_LIST_DETAIL, @"AXDescription"},
+      {ui::AX_ROLE_DESCRIPTION_LIST_TERM, @"AXTerm"},
+      {ui::AX_ROLE_DIALOG, @"AXApplicationDialog"},
+      {ui::AX_ROLE_DOCUMENT, @"AXDocument"},
+      {ui::AX_ROLE_FOOTER, @"AXLandmarkContentInfo"},
+      {ui::AX_ROLE_APPLICATION, @"AXLandmarkApplication"},
+      {ui::AX_ROLE_BANNER, @"AXLandmarkBanner"},
+      {ui::AX_ROLE_COMPLEMENTARY, @"AXLandmarkComplementary"},
+      {ui::AX_ROLE_CONTENT_INFO, @"AXLandmarkContentInfo"},
+      {ui::AX_ROLE_MAIN, @"AXLandmarkMain"},
+      {ui::AX_ROLE_NAVIGATION, @"AXLandmarkNavigation"},
+      {ui::AX_ROLE_SEARCH, @"AXLandmarkSearch"},
+      {ui::AX_ROLE_LOG, @"AXApplicationLog"},
+      {ui::AX_ROLE_MARQUEE, @"AXApplicationMarquee"},
+      {ui::AX_ROLE_MATH, @"AXDocumentMath"},
+      {ui::AX_ROLE_NOTE, @"AXDocumentNote"},
+      {ui::AX_ROLE_REGION, @"AXDocumentRegion"},
+      {ui::AX_ROLE_STATUS, @"AXApplicationStatus"},
+      {ui::AX_ROLE_TAB_PANEL, @"AXTabPanel"},
+      {ui::AX_ROLE_TIMER, @"AXApplicationTimer"},
+      {ui::AX_ROLE_TOGGLE_BUTTON, @"AXToggleButton"},
+      {ui::AX_ROLE_TOOLTIP, @"AXUserInterfaceTooltip"},
+      {ui::AX_ROLE_TREE_ITEM, NSAccessibilityOutlineRowSubrole},
+  };
+
+  RoleMap subrole_map;
+  for (size_t i = 0; i < arraysize(subroles); ++i)
+    subrole_map[subroles[i].value] = subroles[i].nativeValue;
+  return subrole_map;
+}
+
+}  // namespace
+
+@implementation AXPlatformNodeCocoa
+
+// A mapping of AX roles to native roles.
++ (NSString*)nativeRoleFromAXRole:(ui::AXRole)role {
+  CR_DEFINE_STATIC_LOCAL(RoleMap, role_map, (BuildRoleMap()));
+  RoleMap::iterator it = role_map.find(role);
+  return it != role_map.end() ? it->second : NSAccessibilityUnknownRole;
+}
+
+// A mapping of AX roles to native subroles.
++ (NSString*)nativeSubroleFromAXRole:(ui::AXRole)role {
+  CR_DEFINE_STATIC_LOCAL(RoleMap, subrole_map, (BuildSubroleMap()));
+  RoleMap::iterator it = subrole_map.find(role);
+  return it != subrole_map.end() ? it->second : nil;
+}
+
+- (instancetype)initWithNode:(ui::AXPlatformNode*)node {
+  if ((self = [super init])) {
+    node_ = node;
+  }
+  return self;
+}
+
+- (void)detach {
+  node_ = nil;
+}
+
+- (NSRect)boundsInScreen {
+  if (!node_)
+    return NSZeroRect;
+  return gfx::ScreenRectToNSRect(node_->GetBoundsInScreen());
+}
+
+- (BOOL)accessibilityIsIgnored {
+  return [[self AXRole] isEqualToString:NSAccessibilityUnknownRole];
+}
+
+- (id)accessibilityHitTest:(NSPoint)point {
+  for (AXPlatformNodeCocoa* child in [self AXChildren]) {
+    if (NSPointInRect(point, child.boundsInScreen))
+      return [child accessibilityHitTest:point];
+  }
+  return NSAccessibilityUnignoredAncestor(self);
+}
+
+- (NSArray*)accessibilityActionNames {
+  return nil;
+}
+
+- (NSArray*)accessibilityAttributeNames {
+  return @[

[dmazzoni, 2014/07/29 06:35:14]

Cool, no wonder I didn't know about this, I just looked it up and it's only been
part of Obj-C for a short time. Nice.

+    NSAccessibilityChildrenAttribute,
+    NSAccessibilityParentAttribute,
+    NSAccessibilityPositionAttribute,
+    NSAccessibilityRoleAttribute,
+    NSAccessibilitySizeAttribute,
+    NSAccessibilityTitleAttribute,
+  ];
+}
+
+- (BOOL)accessibilityIsAttributeSettable:(NSString*)attribute {
+  return NO;
+}
+
+- (id)accessibilityAttributeValue:(NSString*)attribute {
+  SEL selector = NSSelectorFromString(attribute);
+  if ([self respondsToSelector:selector])
+    return [self performSelector:selector];
+  return nil;
+}
+
+- (NSArray*)AXChildren {
+  if (!node_)
+    return nil;
+  int count = node_->GetChildCount();
+  NSMutableArray* children = [NSMutableArray arrayWithCapacity:count];
+  for (int i = 0; i < count; ++i)
+    [children addObject:node_->ChildAtIndex(i)];
+  return NSAccessibilityUnignoredChildren(children);
+}
+
+- (id)AXParent {
+  if (!node_)
+    return nil;
+  return NSAccessibilityUnignoredAncestor(node_->GetParent());
+}
+
+- (NSValue*)AXPosition {
+  return [NSValue valueWithPoint:self.boundsInScreen.origin];
+}
+
+- (NSString*)AXRole {
+  if (!node_)
+    return nil;
+  return [[self class] nativeRoleFromAXRole:node_->GetRole()];
+}
+
+- (NSValue*)AXSize {
+  return [NSValue valueWithSize:self.boundsInScreen.size];
+}
+
+@end
+
+namespace ui {
+
+// static
+AXPlatformNode* AXPlatformNode::Create(AXPlatformNodeDelegate* delegate) {
+  AXPlatformNode* node = new AXPlatformNodeMac();
+  node->Init(delegate);
+  return node;
+}
+
+AXPlatformNodeMac::AXPlatformNodeMac() {
+}
+
+AXPlatformNodeMac::~AXPlatformNodeMac() {
+}
+
+void AXPlatformNodeMac::Detach() {
+  if (native_node_)
+    [native_node_ detach];
+  delegate_ = NULL;
+  delete this;
+}
+
+gfx::NativeViewAccessible AXPlatformNodeMac::GetNativeViewAccessible() {
+  if (!native_node_)
+    native_node_.reset([[AXPlatformNodeCocoa alloc] initWithNode:this]);
+  return native_node_.get();
+}
+
+}  // namespace ui