Use QObject pointer as QCocoaAccessibleElement id.

Each QCocoaAccessibleElement needs to provide a
unique stable id through the -(NSUnterger)hash
method.

The previous approach of basing the hash on the parent
hash plus the child index is unpractical now that
childAt() can return distant descendants instead
of immediate children only. Use the QObject pointer,
which is set for all accessible interfaces today.

Change-Id: I5868e3a81c1b4da7233504f30003ab8060e9fa3f
Reviewed-by: Morten Johan Sørvig <morten.sorvig@nokia.com>

3 files changed, 14 insertions, 23 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h
index 8251bbcea6..c22c1c84a4 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h
@@ -48,16 +48,13 @@
 @class QCocoaAccessibleElement;
 
 @interface QCocoaAccessibleElement : NSObject {
-    NSUInteger index;
     NSString *role;
     NSObject * parent;
     void *accessibleInterface;
-
 }
 
-- (id)initWithIndex:(int)aIndex parent:(id)aParent accessibleInterface:(void *)anQAccessibleInterface;
-+ (QCocoaAccessibleElement *)elementWithIndex:(int)aIndex parent:(id)aParent accessibleInterface:(void *)anQAccessibleInterface;
-- (NSUInteger)index;
+- (id)initWithInterface:(void *)anQAccessibleInterface parent:(id)aParent;
++ (QCocoaAccessibleElement *)elementWithInterface:(void *)anQAccessibleInterface parent:(id)aParent;
 
 @end
 
diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
index 2d1d5cd1a6..1e9f021543 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
@@ -54,23 +54,21 @@ static QAccessibleInterface *acast(void *ptr)
 
 @implementation QCocoaAccessibleElement
 
-- (id)initWithIndex:(int)aIndex parent:(id)aParent accessibleInterface:(void *)anQAccessibleInterface
+- (id)initWithInterface:(void *)anQAccessibleInterface parent:(id)aParent
 {
     self = [super init];
     if (self) {
-        index = aIndex;
         accessibleInterface = anQAccessibleInterface;
         role = QCocoaAccessible::macRole(acast(accessibleInterface)->role());
         parent = aParent;
-
     }
 
     return self;
 }
 
-+ (QCocoaAccessibleElement *)elementWithIndex:(int)aIndex parent:(id)aParent accessibleInterface:(void *)anQAccessibleInterface
++ (QCocoaAccessibleElement *)elementWithInterface:(void *)anQAccessibleInterface parent:(id)aParent
 {
-    return [[[self alloc] initWithIndex:aIndex parent:aParent accessibleInterface:anQAccessibleInterface] autorelease];
+    return [[[self alloc] initWithInterface:anQAccessibleInterface parent:aParent] autorelease];
 }
 
 - (void)dealloc {
@@ -80,17 +78,14 @@ static QAccessibleInterface *acast(void *ptr)
 - (BOOL)isEqual:(id)object {
     if ([object isKindOfClass:[QCocoaAccessibleElement class]]) {
         QCocoaAccessibleElement *other = object;
-        return (index == other->index) && [role isEqualToString:other->role] && [parent isEqual:other->parent];
-    } else
+        return acast(other->accessibleInterface)->object() == acast(accessibleInterface)->object();
+    } else {
         return NO;
+    }
 }
 
 - (NSUInteger)hash {
-    return [parent hash] + index;
-}
-
-- (NSUInteger)index {
-    return index;
+    return qHash(acast(accessibleInterface)->object());
 }
 
 //
@@ -129,7 +124,7 @@ static QAccessibleInterface *acast(void *ptr)
         NSMutableArray *kids = [NSMutableArray arrayWithCapacity:numKids];
         for (int i = 0; i < numKids; ++i) {
             QAccessibleInterface *childInterface = acast(accessibleInterface)->child(i);
-            [kids addObject:[QCocoaAccessibleElement elementWithIndex:i parent:self accessibleInterface:(void*)childInterface]];
+            [kids addObject:[QCocoaAccessibleElement elementWithInterface:(void*)childInterface parent:self]];
         }
 
         return NSAccessibilityUnignoredChildren(kids);
@@ -232,8 +227,7 @@ static QAccessibleInterface *acast(void *ptr)
     }
 
     // hit a child, forward to child accessible interface.
-    int childIndex = acast(accessibleInterface)->indexOfChild(childInterface);
-    QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithIndex:childIndex parent:self accessibleInterface: childInterface];
+    QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithInterface:childInterface parent:self];
     return [accessibleElement accessibilityHitTest:point];
 }
 
diff --git a/src/plugins/platforms/cocoa/qnsviewaccessibility.mm b/src/plugins/platforms/cocoa/qnsviewaccessibility.mm
index 3c16973c5a..854d292b09 100644
--- a/src/plugins/platforms/cocoa/qnsviewaccessibility.mm
+++ b/src/plugins/platforms/cocoa/qnsviewaccessibility.mm
@@ -75,7 +75,7 @@
         int numKids = m_accessibleRoot->childCount();
         NSMutableArray *kids = [NSMutableArray arrayWithCapacity:numKids];
         for (int i = 0; i < numKids; ++i) {
-            [kids addObject:[QCocoaAccessibleElement elementWithIndex:i parent:self accessibleInterface:(void*)m_accessibleRoot->child(i)]];
+            [kids addObject:[QCocoaAccessibleElement elementWithInterface: m_accessibleRoot->child(i) parent:self ]];
         }
 
         return NSAccessibilityUnignoredChildren(kids);
@@ -96,8 +96,8 @@
     }
 
     // Hit a child, forward to child accessible interface.
-    int childIndex = m_accessibleRoot->indexOfChild(childInterface);
-    QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithIndex:childIndex -1 parent:self accessibleInterface: childInterface];
+
+    QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithInterface: childInterface parent:self ];
     return [accessibleElement accessibilityHitTest:point];
 }