MacViews: Fix VoiceOver feedback in editable fields.

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 <stddef.h>
 
 #include "base/macros.h"
@@ skipping 394 matching lines @@
     case ui::AX_ROLE_TOGGLE_BUTTON:
       [axAttributes addObjectsFromArray:kValueAttributes];
       break;
     // TODO(tapted): Add additional attributes based on role.
     default:
       break;
   }
   return axAttributes.autorelease();
 }
 
+- (NSArray*)accessibilityParameterizedAttributeNames {
+  if (!node_)
+    return nil;
+
+  static NSArray* const kEditableTextAttributes = [@[
+    NSAccessibilityLineForIndexParameterizedAttribute,
+    NSAccessibilityRangeForLineParameterizedAttribute,
+    NSAccessibilityStringForRangeParameterizedAttribute,
+    NSAccessibilityRangeForPositionParameterizedAttribute,
+    NSAccessibilityRangeForIndexParameterizedAttribute,
+    NSAccessibilityBoundsForRangeParameterizedAttribute,
+    NSAccessibilityRTFForRangeParameterizedAttribute,
+    NSAccessibilityStyleRangeForIndexParameterizedAttribute,
+    NSAccessibilityAttributedStringForRangeParameterizedAttribute,
+  ] retain];
+
+  switch (node_->GetData().role) {
+    case ui::AX_ROLE_TEXT_FIELD:
+    case ui::AX_ROLE_STATIC_TEXT:
+      return kEditableTextAttributes;

[dmazzoni, 2017/06/26 16:50:05]

If we're exposing these for STATIC_TEXT, maybe a better
name would be kSelectableTextAttributes?

[tapted, 2017/06/27 00:56:24]

Good point! Done.

+    default:
+      break;
+  }
+  return nil;
+}
+
 - (BOOL)accessibilityIsAttributeSettable:(NSString*)attributeName {
   if (node_->GetData().HasState(ui::AX_STATE_DISABLED))
     return NO;
 
   // Allow certain attributes to be written via an accessibility client. A
   // writable attribute will only appear as such if the accessibility element
   // has a value set for that attribute.
   if ([attributeName
           isEqualToString:NSAccessibilitySelectedChildrenAttribute] ||
       [attributeName
@@ skipping 62 matching lines @@
   // specified in accessibilityIsAttributeSettable.
 }
 
 - (id)accessibilityAttributeValue:(NSString*)attribute {
   SEL selector = NSSelectorFromString(attribute);
   if ([self respondsToSelector:selector])
     return [self performSelector:selector];
   return nil;
 }
 
+- (id)accessibilityAttributeValue:(NSString*)attribute
+                     forParameter:(id)parameter {
+  SEL selector = NSSelectorFromString([attribute stringByAppendingString:@":"]);
+  if ([self respondsToSelector:selector])
+    return [self performSelector:selector withObject:parameter];
+  return nil;
+}
+
 // NSAccessibility attributes. Order them according to
 // NSAccessibilityConstants.h, or see https://crbug.com/678898.
 
 - (NSString*)AXRole {
   if (!node_)
     return nil;
   return [[self class] nativeRoleFromAXRole:node_->GetData().role];
 }
 
 - (NSString*)AXRoleDescription {
@@ skipping 119 matching lines @@
 
 - (NSValue*)AXVisibleCharacterRange {
   return [NSValue valueWithRange:{0, [[self getAXValueAsString] length]}];
 }
 
 - (NSNumber*)AXInsertionPointLineNumber {
   // Multiline is not supported on views.
   return @0;
 }
 
+// Parameterized text-specific attributes.
+
+- (id)AXLineForIndex:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSNumber class]]);
+  // Multiline is not supported on views.
+  return @0;

[tapted, 2017/06/26 09:18:51]

This matches what's currently done for AXInsertionPointLineNumber

for more complex stuff, we probably want to continue with that AXTextMarker
refactoring, and share the same logic.

+}
+
+- (id)AXRangeForLine:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSNumber class]]);
+  DCHECK_EQ(0, [parameter intValue]);
+  return [NSValue valueWithRange:{0, [[self getAXValueAsString] length]}];
+}
+
+- (id)AXStringForRange:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSValue class]]);
+  return [[self getAXValueAsString] substringWithRange:[parameter rangeValue]];
+}
+
+- (id)AXRangeForPosition:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSValue class]]);
+  // TODO(tapted): Hit-test [parameter pointValue] and return an NSRange.
+  NOTIMPLEMENTED();
+  return nil;
+}
+
+- (id)AXRangeForIndex:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSNumber class]]);
+  NOTIMPLEMENTED();
+  return nil;
+}
+
+- (id)AXBoundsForRange:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSValue class]]);
+  // TODO(tapted): Provide an accessor on AXPlatformNodeDelegate to obtain this
+  // from ui::TextInputClient::GetCompositionCharacterBounds().
+  NOTIMPLEMENTED();

[tapted, 2017/06/26 09:18:51]

This is the only one I've been able to hit with basic voiceover usage. returning
nil just means it highlights the view bounds instead

+  return nil;
+}
+
+- (id)AXRTFForRange:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSValue class]]);
+  NOTIMPLEMENTED();
+  return nil;
+}
+
+- (id)AXStyleRangeForIndex:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSNumber class]]);
+  NOTIMPLEMENTED();
+  return nil;
+}
+
+- (id)AXAttributedStringForRange:(id)parameter {
+  DCHECK([parameter isKindOfClass:[NSValue class]]);
+  base::scoped_nsobject<NSAttributedString> attributedString(
+      [[NSAttributedString alloc]
+          initWithString:[self AXStringForRange:parameter]]);
+  // TODO(tapted): views::WordLookupClient has a way to obtain the actual
+  // decorations, and BridgedContentView has a conversion function that creates
+  // an NSAttributedString. Refactor things so they can be used here.
+  return attributedString.autorelease();
+}
+
 @end
 
 namespace ui {
 
 // static
 AXPlatformNode* AXPlatformNode::Create(AXPlatformNodeDelegate* delegate) {
   AXPlatformNodeBase* node = new AXPlatformNodeMac();
   node->Init(delegate);
   return node;
 }
@@ skipping 41 matching lines @@
   }
   NotifyMacEvent(native_node_, event_type);
 }
 
 int AXPlatformNodeMac::GetIndexInParent() {
   // TODO(dmazzoni): implement this.  http://crbug.com/396137
   return -1;
 }
 
 }  // namespace ui