Bug 288017: proper init/shudown for list items and list bullet accessibles. r=pkw, sr=neil

accessible/src/html/nsHTMLTextAccessible.cpp

@@ -165,11 +165,16 @@ NS_IMETHODIMP nsHTMLLabelAccessible::GetChildCount(PRInt32 *aAccChildCount)
 
 nsHTMLLIAccessible::nsHTMLLIAccessible(nsIDOMNode *aDOMNode, nsIWeakReference* aShell, 
                    nsIFrame *aBulletFrame, const nsAString& aBulletText):
-  nsAccessibleWrap(aDOMNode, aShell),
-  mBulletAccessible(aBulletText.IsEmpty() ? nsnull : 
-                    new nsHTMLListBulletAccessible(mDOMNode, mWeakShell, 
-                                                   aBulletFrame, aBulletText))
+  nsAccessibleWrap(aDOMNode, aShell)
 {
+  if (!aBulletText.IsEmpty()) {
+    mBulletAccessible = new nsHTMLListBulletAccessible(mDOMNode, mWeakShell, 
+                                                       aBulletFrame, aBulletText);
+    nsCOMPtr<nsPIAccessNode> bulletANode(mBulletAccessible);
+    if (bulletANode) {
+      bulletANode->Init();
+    }
+  }
 }
 
 NS_IMETHODIMP nsHTMLLIAccessible::GetBounds(PRInt32 *x, PRInt32 *y, PRInt32 *width, PRInt32 *height)
@@ -202,7 +207,7 @@ void nsHTMLLIAccessible::CacheChildren(PRBool aWalkAnonContent)
     walker.mState.frame = GetFrame();
     walker.GetFirstChild();
 
-    nsCOMPtr<nsPIAccessible> privatePrevAccessible = do_QueryInterface(mBulletAccessible);
+    nsCOMPtr<nsPIAccessible> privatePrevAccessible = mBulletAccessible;
     while (walker.mState.accessible) {
       ++mAccChildCount;
       privatePrevAccessible->SetNextSibling(walker.mState.accessible);
@@ -220,6 +225,20 @@ nsHTMLListBulletAccessible::nsHTMLListBulletAccessible(nsIDOMNode* aDomNode,
 {
 }
 
+NS_IMETHODIMP nsHTMLListBulletAccessible::GetUniqueID(void **aUniqueID)
+{
+  // Since mDOMNode is same as for list item, use |this| pointer as the unique Id
+  *aUniqueID = NS_STATIC_CAST(void*, this);
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP nsHTMLListBulletAccessible::Shutdown()
+{
+  mBulletText.Truncate();
+  return nsHTMLTextAccessible::Shutdown();
+}
+
 NS_IMETHODIMP nsHTMLListBulletAccessible::GetName(nsAString &aName)
 {
   aName = mBulletText;

accessible/src/html/nsHTMLTextAccessible.h

@@ -41,6 +41,7 @@
 #define _nsHTMLTextAccessible_H_
 
 #include "nsTextAccessibleWrap.h"
+#include "nsAutoPtr.h"
 
 class nsIWeakReference;
 
@@ -80,6 +81,30 @@ public:
   NS_IMETHOD GetChildCount(PRInt32 *aAccChildCount);
 };
 
+class nsHTMLListBulletAccessible : public nsHTMLTextAccessible
+{
+public:
+  nsHTMLListBulletAccessible(nsIDOMNode *aDOMNode, nsIWeakReference* aShell,
+                             nsIFrame *aFrame, const nsAString& aBulletText);
+  NS_IMETHOD GetUniqueID(void **aUniqueID);
+  NS_IMETHOD Shutdown();
+  NS_IMETHOD GetName(nsAString& aName);
+  NS_IMETHOD GetRole(PRUint32 *aRole) { *aRole = ROLE_STATICTEXT; return NS_OK; }
+  NS_IMETHOD GetState(PRUint32 *aState) { nsHTMLTextAccessible::GetState(aState); *aState &= ~STATE_FOCUSABLE; *aState |= STATE_READONLY; return NS_OK; }
+  // Don't cache via unique ID -- bullet accessible shares the same dom node as this LI accessible.
+  // Also, don't cache via mParent/SetParent(), prevent circular reference since li holds onto us.
+  NS_IMETHOD SetParent(nsIAccessible *aParentAccessible) { mParent = nsnull; return NS_OK; }
+protected:
+  // XXX Ideally we'd get the bullet text directly from the bullet frame via
+  // nsBulletFrame::GetListItemText(), but we'd need an interface
+  // for getting text from contentless anonymous frames.
+  // Perhaps something like nsIAnonymousFrame::GetText() ?
+  // However, in practice storing the bullet text here should not be a
+  // problem if we invalidate the right parts of the accessibility cache
+  // when mutation events occur.
+  nsString mBulletText;
+};
+
 class nsHTMLListAccessible : public nsAccessibleWrap
 {
 public:
@@ -94,35 +119,13 @@ class nsHTMLLIAccessible : public nsAccessibleWrap
 public:
   nsHTMLLIAccessible(nsIDOMNode *aDOMNode, nsIWeakReference* aShell, 
                      nsIFrame *aBulletFrame, const nsAString& aBulletText);
-  NS_IMETHOD GetRole(PRUint32 *aRole) {* aRole = ROLE_LISTITEM; return NS_OK; }
+  NS_IMETHOD Shutdown() { nsresult rv = nsAccessibleWrap::Shutdown(); mBulletAccessible = nsnull; return rv; }
+  NS_IMETHOD GetRole(PRUint32 *aRole) { *aRole = ROLE_LISTITEM; return NS_OK; }
   NS_IMETHOD GetState(PRUint32 *aState) { nsAccessibleWrap::GetState(aState); *aState &= ~STATE_FOCUSABLE; *aState |= STATE_READONLY; return NS_OK; }
   NS_IMETHOD GetBounds(PRInt32 *x, PRInt32 *y, PRInt32 *width, PRInt32 *height);
   void CacheChildren(PRBool aWalkAnonContent);  // Include bullet accessible
 protected:
-  nsCOMPtr<nsIAccessible> mBulletAccessible;
-};
-
-class nsHTMLListBulletAccessible : public nsHTMLTextAccessible
-{
-public:
-  nsHTMLListBulletAccessible(nsIDOMNode *aDOMNode, nsIWeakReference* aShell,
-                             nsIFrame *aFrame, const nsAString& aBulletText);
-  NS_IMETHOD GetName(nsAString& aName);
-  NS_IMETHOD GetRole(PRUint32 *aRole) { *aRole = ROLE_STATICTEXT; return NS_OK; }
-  NS_IMETHOD GetState(PRUint32 *aState) { nsHTMLTextAccessible::GetState(aState); *aState &= ~STATE_FOCUSABLE; *aState |= STATE_READONLY; return NS_OK; }
-  // Don't cache via unique ID -- bullet accessible shares the same dom node as this LI accessible.
-  // Also, don't cache via mParent/SetParent(), prevent circular reference since li holds onto us.
-  NS_IMETHOD SetParent(nsIAccessible *aParentAccessible) { mParent = nsnull; return NS_OK; }
-protected:
-  // XXX Ideally we'd get the bullet text directly from the bullet frame via
-  // nsBulletFrame::GetListItemText(), but we'd need an interface
-  // for getting text from contentless anonymous frames.
-  // Perhaps something like nsIAnonymousFrame::GetText() ?
-  // However, in practice storing the bullet text here should not be a
-  // problem if we invalidate the right parts of the accessibility cache
-  // when mutation events occur. We'll also need to watch for mere style
-  // changes -- perhaps we need to look for reflows and their reasons.
-  nsString mBulletText;
+  nsRefPtr<nsHTMLListBulletAccessible> mBulletAccessible;
 };
 
 #endif