add new method to ensure that tree content is visible: go through all the presentation shells, and call EnsureRowIsVisible for each tree.

also expose a method to get the visible row for a tree - I needed it anyway, figured I might as well expose it from JS.
other half of fix for #12895
r=bryner


git-svn-id: svn://10.0.0.236/trunk@56942 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/content/xul/content/src/nsXULTreeElement.cpp

@@ -34,9 +34,14 @@
 #include "nsIPresContext.h"
 #include "nsIPresShell.h"
 #include "nsINameSpaceManager.h"
+#include "nsIFrame.h"
+#include "nsITreeFrame.h"
 #include "nsString.h"
 
 nsIAtom*             nsXULTreeElement::kSelectedAtom;
+nsIAtom*             nsXULTreeElement::kOpenAtom;
+nsIAtom*             nsXULTreeElement::kTreeRowAtom;
+nsIAtom*             nsXULTreeElement::kTreeItemAtom;
 int                  nsXULTreeElement::gRefCnt = 0;
 
 NS_IMPL_ADDREF_INHERITED(nsXULTreeElement, nsXULAggregateElement);
@@ -69,6 +74,9 @@ nsXULTreeElement::nsXULTreeElement(nsIDOMXULElement* aOuter)
 {
   if (gRefCnt++ == 0) {
     kSelectedAtom    = NS_NewAtom("selected");
+    kOpenAtom        = NS_NewAtom("open");
+    kTreeRowAtom     = NS_NewAtom("treerow");
+    kTreeItemAtom    = NS_NewAtom("treeitem");
   }
 
   nsresult rv;
@@ -382,3 +390,125 @@ nsXULTreeElement::FireOnSelectHandler()
   return NS_OK;
 }
 
+nsresult
+nsXULTreeElement::GetRowIndexOf(nsIDOMXULElement *aElement, PRInt32 *aReturn)
+{
+  NS_ENSURE_ARG_POINTER(aElement);
+  NS_ENSURE_ARG_POINTER(aReturn);
+
+  nsresult rv;
+
+  nsCOMPtr<nsIContent> elementContent = do_QueryInterface(aElement, &rv);
+  if (NS_FAILED(rv)) return rv;
+
+  nsCOMPtr<nsIContent> treeContent =
+    do_QueryInterface((nsIXULTreeContent*)this,&rv);
+  if (NS_FAILED(rv)) return rv;
+  
+  *aReturn = 0;
+
+  return IndexOfContent(treeContent, elementContent, aReturn);
+}
+
+
+nsresult
+nsXULTreeElement::EnsureElementIsVisible(nsIDOMXULElement *aElement)
+{
+  if (!aElement) return NS_OK;
+
+  nsresult rv;
+  
+  PRInt32 indexOfContent;
+  rv = GetRowIndexOf(aElement, &indexOfContent);
+  if (NS_FAILED(rv)) return rv;
+
+  nsCOMPtr<nsIContent> content = do_QueryInterface(mOuter);
+  nsCOMPtr<nsIDocument> document;
+  content->GetDocument(*getter_AddRefs(document));
+
+  // If there's no document (e.g., a selection is occuring in a
+  // 'orphaned' node), then there ain't a whole lot to do here!
+  if (! document) {
+    NS_WARNING("Trying to EnsureElementIsVisible on orphaned element!");
+    return NS_OK;
+  }
+
+  // now call EnsureElementIsVisible on all the frames
+  PRInt32 count = document->GetNumberOfShells();
+	for (PRInt32 i = 0; i < count; i++) {
+		nsCOMPtr<nsIPresShell> shell = document->GetShellAt(i);
+		if (!shell)
+				continue;
+
+    nsIFrame *frame;
+    shell->GetPrimaryFrameFor(content, &frame);
+
+    if (frame) {
+      nsITreeFrame *treeFrame = nsnull;      
+      rv = frame->QueryInterface(NS_GET_IID(nsITreeFrame),
+                                 (void **)&treeFrame);
+      if (NS_SUCCEEDED(rv) && treeFrame) {
+        treeFrame->EnsureRowIsVisible(indexOfContent);
+      }
+    }
+
+  }
+
+  return NS_OK;
+  
+  
+}
+
+
+// helper routine for GetRowIndexOf()
+// walks the DOM to get the zero-based row index of the current content
+// note that aContent can be any element, this will get the index of the
+// element's parent
+nsresult
+nsXULTreeElement::IndexOfContent(nsIContent* aRoot,
+                                 nsIContent* aContent,
+                                 PRInt32 *aResult)
+{
+  // number of rows that are direct children of aRoot
+  // on success, add this to aResult
+  PRInt32 rows=0;
+  
+  PRInt32 childCount=0;
+  aRoot->ChildCount(childCount);
+  
+  PRInt32 childIndex;
+  for (childIndex=0; childIndex<childCount; childIndex++) {
+    nsCOMPtr<nsIContent> child;
+    aContent->ChildAt(childIndex, *getter_AddRefs(child));
+    
+    nsCOMPtr<nsIAtom> childTag;
+    child->GetTag(*getter_AddRefs(childTag));
+
+    // we hit a treerow, count it
+    if (childTag.get() == kTreeRowAtom)
+      rows++;
+    
+    // is this it?
+    if (child.get() == aContent) {
+      *aResult += rows;
+      return NS_OK;
+    }
+
+    // check children only if open="true"
+    if (childTag.get() == kTreeItemAtom) {
+      nsAutoString isOpen;
+      child->GetAttribute(kNameSpaceID_None, kOpenAtom, isOpen);
+
+      if (isOpen == "true" &&
+          NS_SUCCEEDED(IndexOfContent(child, aContent, aResult))) {
+        
+        *aResult += rows;
+        return NS_OK;
+      }
+    }
+  }
+
+  // not found
+  return NS_ERROR_FAILURE;
+}
+

mozilla/content/xul/content/src/nsXULTreeElement.h

@@ -60,6 +60,9 @@ public:
     NS_IMETHOD FireOnSelectHandler();
 
     static nsIAtom*             kSelectedAtom;
+    static nsIAtom*             kOpenAtom;
+    static nsIAtom*             kTreeRowAtom;
+    static nsIAtom*             kTreeItemAtom;
     static int gRefCnt;
 
 protected:
@@ -70,7 +73,9 @@ protected:
     void RemoveItemFromSelectionInternal(nsIDOMXULElement* aTreeItem);
     void AddCellToSelectionInternal(nsIDOMXULElement* aTreeCell);
     void RemoveCellFromSelectionInternal(nsIDOMXULElement* aTreeCell);
-
+    
+    static nsresult IndexOfContent(nsIContent *aRoot, nsIContent *aContent,
+                               PRInt32* aResult);
 protected:
     nsRDFDOMNodeList* mSelectedItems;
     nsRDFDOMNodeList* mSelectedCells;

mozilla/dom/public/idl/xul/XULTreeElement.idl

@@ -24,4 +24,7 @@ interface XULTreeElement : XULElement {
 
   void selectAll();
   void invertSelection();
+
+  void ensureElementIsVisible(in XULElement element);
+  long getRowIndexOf(in XULElement element);
 };

mozilla/dom/public/nsDOMPropEnums.h

@@ -905,6 +905,8 @@ enum nsDOMProp {
     NS_DOM_PROP_XULTREEELEMENT_SELECTITEMRANGE,
     NS_DOM_PROP_XULTREEELEMENT_TOGGLECELLSELECTION,
     NS_DOM_PROP_XULTREEELEMENT_TOGGLEITEMSELECTION,
+    NS_DOM_PROP_XULTREEELEMENT_ENSUREELEMENTISVISIBLE,
+    NS_DOM_PROP_XULTREEELEMENT_GETROWINDEXOF,
     NS_DOM_PROP_MAX
 };
 

mozilla/dom/public/xul/nsIDOMXULTreeElement.h

@@ -71,6 +71,10 @@ public:
   NS_IMETHOD    SelectAll()=0;
 
   NS_IMETHOD    InvertSelection()=0;
+
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement)=0;
+
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn)=0;
 };
 
 
@@ -91,6 +95,8 @@ public:
   NS_IMETHOD    SelectCellRange(nsIDOMXULElement* aStartItem, nsIDOMXULElement* aEndItem);  \
   NS_IMETHOD    SelectAll();  \
   NS_IMETHOD    InvertSelection();  \
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement);  \
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn);  \
 
 
 
@@ -111,6 +117,8 @@ public:
   NS_IMETHOD    SelectCellRange(nsIDOMXULElement* aStartItem, nsIDOMXULElement* aEndItem) { return _to SelectCellRange(aStartItem, aEndItem); }  \
   NS_IMETHOD    SelectAll() { return _to SelectAll(); }  \
   NS_IMETHOD    InvertSelection() { return _to InvertSelection(); }  \
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement) { return _to EnsureElementIsVisible(aElement); }  \
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn) { return _to GetRowIndexOf(aElement, aReturn); }  \
 
 
 extern "C" NS_DOM nsresult NS_InitXULTreeElementClass(nsIScriptContext *aContext, void **aPrototype);

mozilla/dom/src/xul/nsJSXULTreeElement.cpp

@@ -942,6 +942,119 @@ XULTreeElementInvertSelection(JSContext *cx, JSObject *obj, uintN argc, jsval *a
 }
 
 
+//
+// Native method EnsureElementIsVisible
+//
+PR_STATIC_CALLBACK(JSBool)
+XULTreeElementEnsureElementIsVisible(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
+{
+  nsIDOMXULTreeElement *nativeThis = (nsIDOMXULTreeElement*)nsJSUtils::nsGetNativeThis(cx, obj);
+  nsresult result = NS_OK;
+  nsCOMPtr<nsIDOMXULElement> b0;
+  // If there's no private data, this must be the prototype, so ignore
+  if (nsnull == nativeThis) {
+    return JS_TRUE;
+  }
+
+  {
+
+  *rval = JSVAL_NULL;
+
+  {
+    PRBool ok;
+    nsresult rv;
+    NS_WITH_SERVICE(nsIScriptSecurityManager, secMan,
+                    NS_SCRIPTSECURITYMANAGER_PROGID, &rv);
+    if (NS_FAILED(rv)) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECMAN_ERR);
+    }
+    secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_XULTREEELEMENT_ENSUREELEMENTISVISIBLE, PR_FALSE, &ok);
+    if (!ok) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECURITY_ERR);
+    }
+  }
+
+    if (argc < 1) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_TOO_FEW_PARAMETERS_ERR);
+    }
+
+    if (JS_FALSE == nsJSUtils::nsConvertJSValToObject((nsISupports **)(void**)getter_AddRefs(b0),
+                                           kIXULElementIID,
+                                           "XULElement",
+                                           cx,
+                                           argv[0])) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_NOT_OBJECT_ERR);
+    }
+
+    result = nativeThis->EnsureElementIsVisible(b0);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+
+    *rval = JSVAL_VOID;
+  }
+
+  return JS_TRUE;
+}
+
+
+//
+// Native method GetRowIndexOf
+//
+PR_STATIC_CALLBACK(JSBool)
+XULTreeElementGetRowIndexOf(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
+{
+  nsIDOMXULTreeElement *nativeThis = (nsIDOMXULTreeElement*)nsJSUtils::nsGetNativeThis(cx, obj);
+  nsresult result = NS_OK;
+  PRInt32 nativeRet;
+  nsCOMPtr<nsIDOMXULElement> b0;
+  // If there's no private data, this must be the prototype, so ignore
+  if (nsnull == nativeThis) {
+    return JS_TRUE;
+  }
+
+  {
+
+  *rval = JSVAL_NULL;
+
+  {
+    PRBool ok;
+    nsresult rv;
+    NS_WITH_SERVICE(nsIScriptSecurityManager, secMan,
+                    NS_SCRIPTSECURITYMANAGER_PROGID, &rv);
+    if (NS_FAILED(rv)) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECMAN_ERR);
+    }
+    secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_XULTREEELEMENT_GETROWINDEXOF, PR_FALSE, &ok);
+    if (!ok) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECURITY_ERR);
+    }
+  }
+
+    if (argc < 1) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_TOO_FEW_PARAMETERS_ERR);
+    }
+
+    if (JS_FALSE == nsJSUtils::nsConvertJSValToObject((nsISupports **)(void**)getter_AddRefs(b0),
+                                           kIXULElementIID,
+                                           "XULElement",
+                                           cx,
+                                           argv[0])) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_NOT_OBJECT_ERR);
+    }
+
+    result = nativeThis->GetRowIndexOf(b0, &nativeRet);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+
+    *rval = INT_TO_JSVAL(nativeRet);
+  }
+
+  return JS_TRUE;
+}
+
+
 /***********************************************************************/
 //
 // class for XULTreeElement
@@ -990,6 +1103,8 @@ static JSFunctionSpec XULTreeElementMethods[] =
   {"selectCellRange",          XULTreeElementSelectCellRange,     2},
   {"selectAll",          XULTreeElementSelectAll,     0},
   {"invertSelection",          XULTreeElementInvertSelection,     0},
+  {"ensureElementIsVisible",          XULTreeElementEnsureElementIsVisible,     1},
+  {"getRowIndexOf",          XULTreeElementGetRowIndexOf,     1},
   {0}
 };
 

mozilla/rdf/content/public/idl/XULTreeElement.idl

@@ -24,4 +24,7 @@ interface XULTreeElement : XULElement {
 
   void selectAll();
   void invertSelection();
+
+  void ensureElementIsVisible(in XULElement element);
+  long getRowIndexOf(in XULElement element);
 };

mozilla/rdf/content/public/nsIDOMXULTreeElement.h

@@ -71,6 +71,10 @@ public:
   NS_IMETHOD    SelectAll()=0;
 
   NS_IMETHOD    InvertSelection()=0;
+
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement)=0;
+
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn)=0;
 };
 
 
@@ -91,6 +95,8 @@ public:
   NS_IMETHOD    SelectCellRange(nsIDOMXULElement* aStartItem, nsIDOMXULElement* aEndItem);  \
   NS_IMETHOD    SelectAll();  \
   NS_IMETHOD    InvertSelection();  \
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement);  \
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn);  \
 
 
 
@@ -111,6 +117,8 @@ public:
   NS_IMETHOD    SelectCellRange(nsIDOMXULElement* aStartItem, nsIDOMXULElement* aEndItem) { return _to SelectCellRange(aStartItem, aEndItem); }  \
   NS_IMETHOD    SelectAll() { return _to SelectAll(); }  \
   NS_IMETHOD    InvertSelection() { return _to InvertSelection(); }  \
+  NS_IMETHOD    EnsureElementIsVisible(nsIDOMXULElement* aElement) { return _to EnsureElementIsVisible(aElement); }  \
+  NS_IMETHOD    GetRowIndexOf(nsIDOMXULElement* aElement, PRInt32* aReturn) { return _to GetRowIndexOf(aElement, aReturn); }  \
 
 
 extern "C" NS_DOM nsresult NS_InitXULTreeElementClass(nsIScriptContext *aContext, void **aPrototype);

mozilla/rdf/content/src/nsJSXULTreeElement.cpp

@@ -942,6 +942,119 @@ XULTreeElementInvertSelection(JSContext *cx, JSObject *obj, uintN argc, jsval *a
 }
 
 
+//
+// Native method EnsureElementIsVisible
+//
+PR_STATIC_CALLBACK(JSBool)
+XULTreeElementEnsureElementIsVisible(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
+{
+  nsIDOMXULTreeElement *nativeThis = (nsIDOMXULTreeElement*)nsJSUtils::nsGetNativeThis(cx, obj);
+  nsresult result = NS_OK;
+  nsCOMPtr<nsIDOMXULElement> b0;
+  // If there's no private data, this must be the prototype, so ignore
+  if (nsnull == nativeThis) {
+    return JS_TRUE;
+  }
+
+  {
+
+  *rval = JSVAL_NULL;
+
+  {
+    PRBool ok;
+    nsresult rv;
+    NS_WITH_SERVICE(nsIScriptSecurityManager, secMan,
+                    NS_SCRIPTSECURITYMANAGER_PROGID, &rv);
+    if (NS_FAILED(rv)) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECMAN_ERR);
+    }
+    secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_XULTREEELEMENT_ENSUREELEMENTISVISIBLE, PR_FALSE, &ok);
+    if (!ok) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECURITY_ERR);
+    }
+  }
+
+    if (argc < 1) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_TOO_FEW_PARAMETERS_ERR);
+    }
+
+    if (JS_FALSE == nsJSUtils::nsConvertJSValToObject((nsISupports **)(void**)getter_AddRefs(b0),
+                                           kIXULElementIID,
+                                           "XULElement",
+                                           cx,
+                                           argv[0])) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_NOT_OBJECT_ERR);
+    }
+
+    result = nativeThis->EnsureElementIsVisible(b0);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+
+    *rval = JSVAL_VOID;
+  }
+
+  return JS_TRUE;
+}
+
+
+//
+// Native method GetRowIndexOf
+//
+PR_STATIC_CALLBACK(JSBool)
+XULTreeElementGetRowIndexOf(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
+{
+  nsIDOMXULTreeElement *nativeThis = (nsIDOMXULTreeElement*)nsJSUtils::nsGetNativeThis(cx, obj);
+  nsresult result = NS_OK;
+  PRInt32 nativeRet;
+  nsCOMPtr<nsIDOMXULElement> b0;
+  // If there's no private data, this must be the prototype, so ignore
+  if (nsnull == nativeThis) {
+    return JS_TRUE;
+  }
+
+  {
+
+  *rval = JSVAL_NULL;
+
+  {
+    PRBool ok;
+    nsresult rv;
+    NS_WITH_SERVICE(nsIScriptSecurityManager, secMan,
+                    NS_SCRIPTSECURITYMANAGER_PROGID, &rv);
+    if (NS_FAILED(rv)) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECMAN_ERR);
+    }
+    secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_XULTREEELEMENT_GETROWINDEXOF, PR_FALSE, &ok);
+    if (!ok) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_SECURITY_ERR);
+    }
+  }
+
+    if (argc < 1) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_TOO_FEW_PARAMETERS_ERR);
+    }
+
+    if (JS_FALSE == nsJSUtils::nsConvertJSValToObject((nsISupports **)(void**)getter_AddRefs(b0),
+                                           kIXULElementIID,
+                                           "XULElement",
+                                           cx,
+                                           argv[0])) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_NOT_OBJECT_ERR);
+    }
+
+    result = nativeThis->GetRowIndexOf(b0, &nativeRet);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+
+    *rval = INT_TO_JSVAL(nativeRet);
+  }
+
+  return JS_TRUE;
+}
+
+
 /***********************************************************************/
 //
 // class for XULTreeElement
@@ -990,6 +1103,8 @@ static JSFunctionSpec XULTreeElementMethods[] =
   {"selectCellRange",          XULTreeElementSelectCellRange,     2},
   {"selectAll",          XULTreeElementSelectAll,     0},
   {"invertSelection",          XULTreeElementInvertSelection,     0},
+  {"ensureElementIsVisible",          XULTreeElementEnsureElementIsVisible,     1},
+  {"getRowIndexOf",          XULTreeElementGetRowIndexOf,     1},
   {0}
 };
 

mozilla/rdf/content/src/nsXULTreeElement.cpp

@@ -34,9 +34,14 @@
 #include "nsIPresContext.h"
 #include "nsIPresShell.h"
 #include "nsINameSpaceManager.h"
+#include "nsIFrame.h"
+#include "nsITreeFrame.h"
 #include "nsString.h"
 
 nsIAtom*             nsXULTreeElement::kSelectedAtom;
+nsIAtom*             nsXULTreeElement::kOpenAtom;
+nsIAtom*             nsXULTreeElement::kTreeRowAtom;
+nsIAtom*             nsXULTreeElement::kTreeItemAtom;
 int                  nsXULTreeElement::gRefCnt = 0;
 
 NS_IMPL_ADDREF_INHERITED(nsXULTreeElement, nsXULAggregateElement);
@@ -69,6 +74,9 @@ nsXULTreeElement::nsXULTreeElement(nsIDOMXULElement* aOuter)
 {
   if (gRefCnt++ == 0) {
     kSelectedAtom    = NS_NewAtom("selected");
+    kOpenAtom        = NS_NewAtom("open");
+    kTreeRowAtom     = NS_NewAtom("treerow");
+    kTreeItemAtom    = NS_NewAtom("treeitem");
   }
 
   nsresult rv;
@@ -382,3 +390,125 @@ nsXULTreeElement::FireOnSelectHandler()
   return NS_OK;
 }
 
+nsresult
+nsXULTreeElement::GetRowIndexOf(nsIDOMXULElement *aElement, PRInt32 *aReturn)
+{
+  NS_ENSURE_ARG_POINTER(aElement);
+  NS_ENSURE_ARG_POINTER(aReturn);
+
+  nsresult rv;
+
+  nsCOMPtr<nsIContent> elementContent = do_QueryInterface(aElement, &rv);
+  if (NS_FAILED(rv)) return rv;
+
+  nsCOMPtr<nsIContent> treeContent =
+    do_QueryInterface((nsIXULTreeContent*)this,&rv);
+  if (NS_FAILED(rv)) return rv;
+  
+  *aReturn = 0;
+
+  return IndexOfContent(treeContent, elementContent, aReturn);
+}
+
+
+nsresult
+nsXULTreeElement::EnsureElementIsVisible(nsIDOMXULElement *aElement)
+{
+  if (!aElement) return NS_OK;
+
+  nsresult rv;
+  
+  PRInt32 indexOfContent;
+  rv = GetRowIndexOf(aElement, &indexOfContent);
+  if (NS_FAILED(rv)) return rv;
+
+  nsCOMPtr<nsIContent> content = do_QueryInterface(mOuter);
+  nsCOMPtr<nsIDocument> document;
+  content->GetDocument(*getter_AddRefs(document));
+
+  // If there's no document (e.g., a selection is occuring in a
+  // 'orphaned' node), then there ain't a whole lot to do here!
+  if (! document) {
+    NS_WARNING("Trying to EnsureElementIsVisible on orphaned element!");
+    return NS_OK;
+  }
+
+  // now call EnsureElementIsVisible on all the frames
+  PRInt32 count = document->GetNumberOfShells();
+	for (PRInt32 i = 0; i < count; i++) {
+		nsCOMPtr<nsIPresShell> shell = document->GetShellAt(i);
+		if (!shell)
+				continue;
+
+    nsIFrame *frame;
+    shell->GetPrimaryFrameFor(content, &frame);
+
+    if (frame) {
+      nsITreeFrame *treeFrame = nsnull;      
+      rv = frame->QueryInterface(NS_GET_IID(nsITreeFrame),
+                                 (void **)&treeFrame);
+      if (NS_SUCCEEDED(rv) && treeFrame) {
+        treeFrame->EnsureRowIsVisible(indexOfContent);
+      }
+    }
+
+  }
+
+  return NS_OK;
+  
+  
+}
+
+
+// helper routine for GetRowIndexOf()
+// walks the DOM to get the zero-based row index of the current content
+// note that aContent can be any element, this will get the index of the
+// element's parent
+nsresult
+nsXULTreeElement::IndexOfContent(nsIContent* aRoot,
+                                 nsIContent* aContent,
+                                 PRInt32 *aResult)
+{
+  // number of rows that are direct children of aRoot
+  // on success, add this to aResult
+  PRInt32 rows=0;
+  
+  PRInt32 childCount=0;
+  aRoot->ChildCount(childCount);
+  
+  PRInt32 childIndex;
+  for (childIndex=0; childIndex<childCount; childIndex++) {
+    nsCOMPtr<nsIContent> child;
+    aContent->ChildAt(childIndex, *getter_AddRefs(child));
+    
+    nsCOMPtr<nsIAtom> childTag;
+    child->GetTag(*getter_AddRefs(childTag));
+
+    // we hit a treerow, count it
+    if (childTag.get() == kTreeRowAtom)
+      rows++;
+    
+    // is this it?
+    if (child.get() == aContent) {
+      *aResult += rows;
+      return NS_OK;
+    }
+
+    // check children only if open="true"
+    if (childTag.get() == kTreeItemAtom) {
+      nsAutoString isOpen;
+      child->GetAttribute(kNameSpaceID_None, kOpenAtom, isOpen);
+
+      if (isOpen == "true" &&
+          NS_SUCCEEDED(IndexOfContent(child, aContent, aResult))) {
+        
+        *aResult += rows;
+        return NS_OK;
+      }
+    }
+  }
+
+  // not found
+  return NS_ERROR_FAILURE;
+}
+

mozilla/rdf/content/src/nsXULTreeElement.h

@@ -60,6 +60,9 @@ public:
     NS_IMETHOD FireOnSelectHandler();
 
     static nsIAtom*             kSelectedAtom;
+    static nsIAtom*             kOpenAtom;
+    static nsIAtom*             kTreeRowAtom;
+    static nsIAtom*             kTreeItemAtom;
     static int gRefCnt;
 
 protected:
@@ -70,7 +73,9 @@ protected:
     void RemoveItemFromSelectionInternal(nsIDOMXULElement* aTreeItem);
     void AddCellToSelectionInternal(nsIDOMXULElement* aTreeCell);
     void RemoveCellFromSelectionInternal(nsIDOMXULElement* aTreeCell);
-
+    
+    static nsresult IndexOfContent(nsIContent *aRoot, nsIContent *aContent,
+                               PRInt32* aResult);
 protected:
     nsRDFDOMNodeList* mSelectedItems;
     nsRDFDOMNodeList* mSelectedCells;