Bug 370416 - <textPath> not updating when referenced path changed.r=longsonr, sr=sicking

layout/svg/base/src/nsSVGTextPathFrame.cpp

@@ -44,13 +44,34 @@
 #include "nsContentUtils.h"
 #include "nsIDOMSVGAnimatedPathData.h"
 #include "nsSVGPathElement.h"
-#include "nsISVGValueUtils.h"
-#include "nsIDOMSVGPathSegList.h"
 
-NS_INTERFACE_MAP_BEGIN(nsSVGTextPathFrame)
-  NS_INTERFACE_MAP_ENTRY(nsISVGValueObserver)
-  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
-NS_INTERFACE_MAP_END_INHERITING(nsSVGTextPathFrameBase)
+
+NS_IMPL_ISUPPORTS1(nsSVGPathListener, nsIMutationObserver)
+
+nsSVGPathListener::nsSVGPathListener(nsIContent *aPathElement,
+                                     nsSVGTextPathFrame *aTextPathFrame) :
+  mTextPathFrame(aTextPathFrame)
+{
+  mObservedPath = do_GetWeakReference(aPathElement);
+  aPathElement->AddMutationObserver(this);
+}
+
+nsSVGPathListener::~nsSVGPathListener()
+{
+  nsCOMPtr<nsIContent> path = do_QueryReferent(mObservedPath);
+  if (path)
+    path->RemoveMutationObserver(this);
+}
+
+void
+nsSVGPathListener::AttributeChanged(nsIDocument *aDocument,
+                                    nsIContent *aContent,
+                                    PRInt32 aNameSpaceID,
+                                    nsIAtom *aAttribute,
+                                    PRInt32 aModType)
+{
+  mTextPathFrame->UpdateGraphic();
+}
 
 //----------------------------------------------------------------------
 // Implementation
@@ -75,12 +96,6 @@ NS_NewSVGTextPathFrame(nsIPresShell* aPresShell, nsIContent* aContent,
   return new (aPresShell) nsSVGTextPathFrame(aContext);
 }
 
-nsSVGTextPathFrame::~nsSVGTextPathFrame()
-{
-  if (mSegments)
-    NS_REMOVE_SVGVALUE_OBSERVER(mSegments);
-}
-
 NS_IMETHODIMP
 nsSVGTextPathFrame::Init(nsIContent*      aContent,
                          nsIFrame*        aParent,
@@ -193,40 +208,18 @@ nsSVGTextPathFrame::GetFlattenedPath() {
   if (!path)
     return nsnull;
 
-  if (!mSegments) {
-    nsCOMPtr<nsIDOMSVGAnimatedPathData> data =
-      do_QueryInterface(path->GetContent());
-    if (data) {
-      data->GetAnimatedPathSegList(getter_AddRefs(mSegments));
-      NS_ADD_SVGVALUE_OBSERVER(mSegments);
-    }
-  }
-
   nsSVGPathGeometryElement *element = NS_STATIC_CAST(nsSVGPathGeometryElement*,
                                                      path->GetContent());
+
+  if (!mPathListener) {
+    mPathListener = new nsSVGPathListener(path->GetContent(), this);
+  }
+
   nsCOMPtr<nsIDOMSVGMatrix> localTM = element->GetLocalTransformMatrix();
 
   return element->GetFlattenedPath(localTM);
 }
 
-//----------------------------------------------------------------------
-// nsISVGValueObserver methods:
-
-NS_IMETHODIMP
-nsSVGTextPathFrame::WillModifySVGObservable(nsISVGValue* observable, 
-                                            nsISVGValue::modificationType aModType)
-{
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsSVGTextPathFrame::DidModifySVGObservable(nsISVGValue* observable,
-                                           nsISVGValue::modificationType aModType)
-{
-  UpdateGraphic();
-  return NS_OK;
-}
-
 //----------------------------------------------------------------------
 // nsIFrame methods
 
@@ -240,8 +233,8 @@ nsSVGTextPathFrame::AttributeChanged(PRInt32         aNameSpaceID,
     UpdateGraphic();
   } else if (aNameSpaceID == kNameSpaceID_XLink &&
              aAttribute == nsGkAtoms::href) {
-    NS_REMOVE_SVGVALUE_OBSERVER(mSegments);
-    mSegments = nsnull;
+    mPathListener = nsnull;
+    UpdateGraphic();
   }
 
   return NS_OK;

layout/svg/base/src/nsSVGTextPathFrame.h

@@ -38,18 +38,34 @@
 #define NSSVGTEXTPATHFRAME_H
 
 #include "nsSVGTSpanFrame.h"
-#include "nsISVGValueObserver.h"
-#include "nsWeakReference.h"
 #include "nsIDOMSVGAnimatedString.h"
-#include "nsIDOMSVGPathSegList.h"
 #include "nsSVGLengthList.h"
 #include "nsIDOMSVGLength.h"
 #include "gfxPath.h"
+#include "nsStubMutationObserver.h"
+
+class nsSVGTextPathFrame;
+
+class nsSVGPathListener : public nsStubMutationObserver {
+public:
+  nsSVGPathListener(nsIContent *aPathElement,
+                    nsSVGTextPathFrame *aTextPathFrame);
+  ~nsSVGPathListener();
+
+  // nsISupports
+  NS_DECL_ISUPPORTS
+
+  // nsIMutationObserver
+  NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
+
+private:
+  nsWeakPtr mObservedPath;
+  nsSVGTextPathFrame *mTextPathFrame;
+};
 
 typedef nsSVGTSpanFrame nsSVGTextPathFrameBase;
 
-class nsSVGTextPathFrame : public nsSVGTextPathFrameBase,
-                           public nsISVGValueObserver
+class nsSVGTextPathFrame : public nsSVGTextPathFrameBase
 {
 public:
   nsSVGTextPathFrame(nsStyleContext* aContext) : nsSVGTextPathFrameBase(aContext) {}
@@ -75,24 +91,11 @@ public:
   }
 #endif
 
-  // nsISVGValueObserver interface:
-  NS_IMETHOD WillModifySVGObservable(nsISVGValue* observable,
-                                     nsISVGValue::modificationType aModType);
-  NS_IMETHOD DidModifySVGObservable(nsISVGValue* observable,
-                                    nsISVGValue::modificationType aModType);
-
   // nsSVGTextPathFrame methods:
   already_AddRefed<gfxFlattenedPath> GetFlattenedPath();
   nsIFrame *GetPathFrame();
 
-   // nsISupports interface:
-  NS_IMETHOD QueryInterface(const nsIID& aIID, void** aInstancePtr);
-private:
-  NS_IMETHOD_(nsrefcnt) AddRef() { return 1; }
-  NS_IMETHOD_(nsrefcnt) Release() { return 1; }
-
 protected:
-  virtual ~nsSVGTextPathFrame();
 
   NS_IMETHOD_(already_AddRefed<nsIDOMSVGLengthList>) GetX();
   NS_IMETHOD_(already_AddRefed<nsIDOMSVGLengthList>) GetY();
@@ -103,9 +106,11 @@ private:
 
   nsCOMPtr<nsIDOMSVGLength> mStartOffset;
   nsCOMPtr<nsIDOMSVGAnimatedString> mHref;
-  nsCOMPtr<nsIDOMSVGPathSegList> mSegments;
+  nsRefPtr<nsSVGPathListener> mPathListener;
 
   nsCOMPtr<nsIDOMSVGLengthList> mX;
+
+  friend class nsSVGPathListener;
 };
 
 #endif