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Diffstat (limited to 'chrome/browser/accessibility/browser_accessibility_cocoa.mm')
| -rw-r--r-- | chrome/browser/accessibility/browser_accessibility_cocoa.mm | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/chrome/browser/accessibility/browser_accessibility_cocoa.mm b/chrome/browser/accessibility/browser_accessibility_cocoa.mm new file mode 100644 index 0000000..0a52a05 --- /dev/null +++ b/chrome/browser/accessibility/browser_accessibility_cocoa.mm @@ -0,0 +1,362 @@ +// Copyright (c) 2010 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. + +#include <execinfo.h> + +#import "chrome/browser/accessibility/browser_accessibility_cocoa.h" + +#include "app/l10n_util_mac.h" +#include "base/string16.h" +#include "base/sys_string_conversions.h" +#include "chrome/browser/renderer_host/render_widget_host_view_mac.h" +#include "grit/webkit_strings.h" +#include "third_party/WebKit/WebKit/chromium/public/WebRect.h" + +namespace { + +// Returns an autoreleased copy of the WebAccessibility's attribute. +NSString* NSStringForWebAccessibilityAttribute( + const std::map<int32, string16>& attributes, + WebAccessibility::Attribute attribute) { + std::map<int32, string16>::const_iterator iter = + attributes.find(attribute); + NSString* returnValue = @""; + if (iter != attributes.end()) { + returnValue = base::SysUTF16ToNSString(iter->second); + } + return returnValue; +} + +struct RoleEntry { + WebAccessibility::Role value; + NSString* string; +}; + +static const RoleEntry roles[] = { + { WebAccessibility::ROLE_NONE, NSAccessibilityUnknownRole }, + { WebAccessibility::ROLE_BUTTON, NSAccessibilityButtonRole }, + { WebAccessibility::ROLE_RADIO_BUTTON, NSAccessibilityRadioButtonRole }, + { WebAccessibility::ROLE_CHECKBOX, NSAccessibilityCheckBoxRole }, + { WebAccessibility::ROLE_STATIC_TEXT, NSAccessibilityStaticTextRole}, + { WebAccessibility::ROLE_IMAGE, NSAccessibilityImageRole}, + { WebAccessibility::ROLE_TEXT_FIELD, NSAccessibilityTextFieldRole}, + { WebAccessibility::ROLE_TEXTAREA, NSAccessibilityTextAreaRole}, + { WebAccessibility::ROLE_LINK, NSAccessibilityLinkRole}, + { WebAccessibility::ROLE_SCROLLAREA, NSAccessibilityScrollAreaRole}, + { WebAccessibility::ROLE_SCROLLBAR, NSAccessibilityScrollBarRole}, + { WebAccessibility::ROLE_RADIO_GROUP, NSAccessibilityRadioGroupRole}, + { WebAccessibility::ROLE_TABLE, NSAccessibilityTableRole}, + { WebAccessibility::ROLE_TAB_GROUP, NSAccessibilityTabGroupRole}, + { WebAccessibility::ROLE_IGNORED, NSAccessibilityUnknownRole}, + { WebAccessibility::ROLE_WEB_AREA, @"AXWebArea"}, + { WebAccessibility::ROLE_GROUP, NSAccessibilityGroupRole}, + { WebAccessibility::ROLE_GRID, NSAccessibilityGridRole}, + { WebAccessibility::ROLE_WEBCORE_LINK, NSAccessibilityLinkRole}, +}; + +// GetState checks the bitmask used in webaccessibility.h to check +// if the given state was set on the accessibility object. +bool GetState(BrowserAccessibility* accessibility, int state) { + return ((accessibility->state() >> state) & 1); +} + +} // namespace + +@implementation BrowserAccessibilityCocoa + +@synthesize browserAccessibility = browserAccessibility_; + +- (id)initWithObject:(BrowserAccessibility*)accessibility + delegate:(id<BrowserAccessibilityDelegateCocoa>)delegate { + if ((self = [super init])) { + browserAccessibility_ = accessibility; + delegate_ = delegate; + } + return self; +} + +// Deletes our associated BrowserAccessibilityMac. +- (void)dealloc { + if (browserAccessibility_) { + delete browserAccessibility_; + browserAccessibility_ = NULL; + } + + [super dealloc]; +} + +// Returns an array of BrowserAccessibilityCocoa objects, representing the +// accessibility children of this object. +- (NSArray*)children { + NSMutableArray* ret = [[[NSMutableArray alloc] + initWithCapacity:browserAccessibility_->GetChildCount()] autorelease]; + for (uint32 index = 0; + index < browserAccessibility_->GetChildCount(); + ++index) { + [ret addObject: + browserAccessibility_->GetChild(index)->toBrowserAccessibilityCocoa()]; + } + return ret; +} + +// Returns whether or not this node should be ignored in the +// accessibility tree. +- (BOOL)isIgnored { + return browserAccessibility_->role() == WebAccessibility::ROLE_IGNORED; +} + +// The origin of this accessibility object in the page's document. +// This is relative to webkit's top-left origin, not Cocoa's +// bottom-left origin. +- (NSPoint)origin { + return NSMakePoint(browserAccessibility_->location().x, + browserAccessibility_->location().y); +} + +// Returns a string indicating the role of this object. +- (NSString*)role { + NSString* role = NSAccessibilityUnknownRole; + WebAccessibility::Role value = + static_cast<WebAccessibility::Role>( browserAccessibility_->role()); + const size_t numRoles = sizeof(roles) / sizeof(roles[0]); + for (size_t i = 0; i < numRoles; ++i) { + if (roles[i].value == value) { + role = roles[i].string; + break; + } + } + return role; +} + +// Returns a string indicating the role description of this object. +- (NSString*)roleDescription { + // The following descriptions are specific to webkit. + if ([[self role] isEqualToString:@"AXWebArea"]) + return l10n_util::GetNSString(IDS_AX_ROLE_WEB_AREA); + + if ([[self role] isEqualToString:@"NSAccessibilityLinkRole"]) + return l10n_util::GetNSString(IDS_AX_ROLE_LINK); + + if ([[self role] isEqualToString:@"AXHeading"]) + return l10n_util::GetNSString(IDS_AX_ROLE_HEADING); + + return NSAccessibilityRoleDescription([self role], nil); +} + +// Returns the size of this object. +- (NSSize)size { + return NSMakeSize(browserAccessibility_->location().width, + browserAccessibility_->location().height); +} + +// Returns the accessibility value for the given attribute. If the value isn't +// supported this will return nil. +- (id)accessibilityAttributeValue:(NSString*)attribute { + if ([attribute isEqualToString:NSAccessibilityRoleAttribute]) { + return [self role]; + } + if ([attribute isEqualToString:NSAccessibilityDescriptionAttribute]) { + return NSStringForWebAccessibilityAttribute( + browserAccessibility_->attributes(), + WebAccessibility::ATTR_DESCRIPTION); + } + if ([attribute isEqualToString:NSAccessibilityPositionAttribute]) { + return [NSValue valueWithPoint:[delegate_ accessibilityPointInScreen:self]]; + } + if ([attribute isEqualToString:NSAccessibilitySizeAttribute]) { + return [NSValue valueWithSize:[self size]]; + } + if ([attribute isEqualToString:NSAccessibilityTopLevelUIElementAttribute] || + [attribute isEqualToString:NSAccessibilityWindowAttribute]) { + return [delegate_ window]; + } + if ([attribute isEqualToString:NSAccessibilityChildrenAttribute]) { + return [self children]; + } + if ([attribute isEqualToString:NSAccessibilityParentAttribute]) { + // A nil parent means we're the root. + if (browserAccessibility_->GetParent()) { + return NSAccessibilityUnignoredAncestor( + browserAccessibility_->GetParent()->toBrowserAccessibilityCocoa()); + } else { + // Hook back up to RenderWidgetHostViewCocoa. + return browserAccessibility_->manager()->GetParentView(); + } + } + if ([attribute isEqualToString:NSAccessibilityTitleAttribute]) { + return base::SysUTF16ToNSString(browserAccessibility_->name()); + } + if ([attribute isEqualToString:NSAccessibilityHelpAttribute]) { + return NSStringForWebAccessibilityAttribute( + browserAccessibility_->attributes(), + WebAccessibility::ATTR_HELP); + } + if ([attribute isEqualToString:NSAccessibilityValueAttribute]) { + return base::SysUTF16ToNSString(browserAccessibility_->value()); + } + if ([attribute isEqualToString:NSAccessibilityRoleDescriptionAttribute]) { + return [self roleDescription]; + } + if ([attribute isEqualToString:NSAccessibilityFocusedAttribute]) { + NSNumber* ret = [NSNumber numberWithBool: + GetState(browserAccessibility_, WebAccessibility::STATE_FOCUSED)]; + return ret; + } + // TODO(dtseng): provide complete implementations for the following. + if ([attribute isEqualToString:NSAccessibilityEnabledAttribute] || + [attribute isEqualToString:@"AXVisited"] || + [attribute isEqualToString:@"AXLoaded"]) { + return [NSNumber numberWithBool:YES]; + } + return nil; +} + +// Returns an array of action names that this object will respond to. +- (NSArray*)accessibilityActionNames { + return [NSArray arrayWithObjects: + NSAccessibilityPressAction, NSAccessibilityShowMenuAction, nil]; +} + +// Returns a sub-array of values for the given attribute value, starting at +// index, with up to maxCount items. If the given index is out of bounds, +// or there are no values for the given attribute, it will return nil. +// This method is used for querying subsets of values, without having to +// return a large set of data, such as elements with a large number of +// children. +- (NSArray*)accessibilityArrayAttributeValues:(NSString*)attribute + index:(NSUInteger)index + maxCount:(NSUInteger)maxCount { + NSArray* fullArray = [self accessibilityAttributeValue:attribute]; + if (!fullArray) + return nil; + NSUInteger arrayCount = [fullArray count]; + if (index >= arrayCount) + return nil; + NSRange subRange; + if ((index + maxCount) > arrayCount) { + subRange = NSMakeRange(index, arrayCount - index); + } else { + subRange = NSMakeRange(index, maxCount); + } + return [fullArray subarrayWithRange:subRange]; +} + +// Returns the count of the specified accessibility array attribute. +- (NSUInteger)accessibilityArrayAttributeCount:(NSString*)attribute { + NSArray* fullArray = [self accessibilityAttributeValue:attribute]; + return [fullArray count]; +} + +// Returns the list of accessibility attributes that this object supports. +- (NSArray*)accessibilityAttributeNames { + return [NSArray arrayWithObjects: + NSAccessibilityChildrenAttribute, + NSAccessibilityDescriptionAttribute, + NSAccessibilityEnabledAttribute, + NSAccessibilityFocusedAttribute, + NSAccessibilityHelpAttribute, + NSAccessibilityParentAttribute, + NSAccessibilityPositionAttribute, + NSAccessibilityRoleAttribute, + NSAccessibilityRoleDescriptionAttribute, + NSAccessibilitySizeAttribute, + NSAccessibilityTitleAttribute, + NSAccessibilityTopLevelUIElementAttribute, + NSAccessibilityValueAttribute, + NSAccessibilityWindowAttribute, + nil]; +} + +// Returns the index of the child in this objects array of children. +- (NSUInteger)accessibilityIndexOfChild:(id)child { + NSUInteger index = 0; + for (BrowserAccessibilityCocoa* childToCheck in [self children]) { + if ([child isEqual:childToCheck]) + return index; + if (![childToCheck isIgnored]) + ++index; + } + return NSNotFound; +} + +// Returns whether or not the specified attribute can be set by the +// accessibility API via |accessibilitySetValue:forAttribute:|. +- (BOOL)accessibilityIsAttributeSettable:(NSString*)attribute { + if ([attribute isEqualToString:NSAccessibilityFocusedAttribute]) + return GetState(browserAccessibility_, WebAccessibility::STATE_FOCUSABLE); + if ([attribute isEqualToString:NSAccessibilityValueAttribute]) + return !GetState(browserAccessibility_, WebAccessibility::STATE_READONLY); + return NO; +} + +// Returns whether or not this object should be ignored in the accessibilty +// tree. +- (BOOL)accessibilityIsIgnored { + return [self isIgnored]; +} + +// Performs the given accessibilty action on the webkit accessibility object +// that backs this object. +- (void)accessibilityPerformAction:(NSString*)action { + // TODO(feldstein): Support more actions. + [delegate_ doDefaultAction:browserAccessibility_->renderer_id()]; +} + +// Returns the description of the given action. +- (NSString*)accessibilityActionDescription:(NSString*)action { + return NSAccessibilityActionDescription(action); +} + +// Sets an override value for a specific accessibility attribute. +// This class does not support this. +- (BOOL)accessibilitySetOverrideValue:(id)value + forAttribute:(NSString*)attribute { + return NO; +} + +// Sets the value for an accessibility attribute via the accessibility API. +- (void)accessibilitySetValue:(id)value forAttribute:(NSString*)attribute { + if ([attribute isEqualToString:NSAccessibilityFocusedAttribute]) { + NSNumber* focusedNumber = value; + BOOL focused = [focusedNumber intValue]; + [delegate_ setAccessibilityFocus:focused + accessibilityId:browserAccessibility_->renderer_id()]; + } +} + +// Returns the deepest accessibility child that should not be ignored. +// It is assumed that the hit test has been narrowed down to this object +// or one of its children, so this will never return nil. +- (id)accessibilityHitTest:(NSPoint)point { + id hit = self; + for (id child in [self children]) { + NSPoint origin = [child origin]; + NSSize size = [child size]; + NSRect rect; + rect.origin = origin; + rect.size = size; + if (NSPointInRect(point, rect)) { + hit = child; + id childResult = [child accessibilityHitTest:point]; + if (![childResult accessibilityIsIgnored]) { + hit = childResult; + break; + } + } + } + return NSAccessibilityUnignoredAncestor(hit); +} + +- (BOOL)isEqual:(id)object { + if (![object isKindOfClass:[BrowserAccessibilityCocoa class]]) + return NO; + return ([self hash] == [object hash]); +} + +- (NSUInteger)hash { + return browserAccessibility_->renderer_id(); +} + +@end + |