Added a helper class to search frame hierarchys.

layout/xul/base/src/Makefile.in

@@ -38,6 +38,7 @@ LOCAL_INCLUDES = \
 
 # Note the sophisticated alphabetical ordering :-|
 CPPSRCS =				\
+	nsFrameNavigator.cpp \
 	nsSplitterFrame.cpp \
 	nsGrippyFrame.cpp \
 	nsTabFrame.cpp \

layout/xul/base/src/makefile.win

@@ -24,6 +24,7 @@ REQUIRES=xpcom raptor pref
 DEFINES=-D_IMPL_NS_HTML -DWIN32_LEAN_AND_MEAN
 
 CPPSRCS=					\
+        nsFrameNavigator.cpp        \
         nsRepeatService.cpp        \
         nsToolbarDragListener.cpp        \
         nsToolbarItemFrame.cpp        \
@@ -58,6 +59,7 @@ CPPSRCS=					\
 	$(NULL)
 
 CPP_OBJS=					\
+        .\$(OBJDIR)\nsFrameNavigator.obj    \
         .\$(OBJDIR)\nsRepeatService.obj    \
         .\$(OBJDIR)\nsToolbarDragListener.obj    \
         .\$(OBJDIR)\nsToolbarItemFrame.obj    \

layout/xul/base/src/nsFrameNavigator.cpp

@@ -0,0 +1,127 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "License"); you may not use this file except in
+ * compliance with the License.  You may obtain a copy of the License at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * The Original Code is Mozilla Communicator client code.
+ *
+ * The Initial Developer of the Original Code is Netscape Communications
+ * Corporation.  Portions created by Netscape are Copyright (C) 1998
+ * Netscape Communications Corporation.  All Rights Reserved.
+ */
+
+//
+// Eric Vaughan
+// Netscape Communications
+//
+// See documentation in associated header file
+//
+
+#include "nsFrameNavigator.h"
+#include "nsCOMPtr.h"
+#include "nsIContent.h"
+
+nsIAtom*
+nsFrameNavigator::GetTag(nsIFrame* frame)
+{
+   nsCOMPtr<nsIContent> content;
+   frame->GetContent(getter_AddRefs(content));
+   if (content) {
+     nsIAtom* atom = nsnull;
+     content->GetTag(atom);
+     return atom; 
+   }
+
+   return nsnull;
+}
+
+nsIFrame*
+nsFrameNavigator::GetChildBeforeAfter(nsIFrame* start, PRBool before)
+{
+   nsIFrame* parent = nsnull;
+   start->GetParent(&parent);
+   PRInt32 index = IndexOf(parent,start);
+   PRInt32 count = CountFrames(parent);
+
+   if (index == -1) 
+     return nsnull;
+
+   if (before) {
+     if (index == 0) {
+         return nsnull;
+     }
+
+     return GetChildAt(parent, index-1);
+   }
+
+
+   if (index == count-1)
+       return nsnull;
+
+   return GetChildAt(parent, index+1);
+}
+
+PRInt32
+nsFrameNavigator::IndexOf(nsIFrame* parent, nsIFrame* child)
+{
+  PRInt32 count = 0;
+
+  nsIFrame* childFrame;
+  parent->FirstChild(nsnull, &childFrame); 
+  while (nsnull != childFrame) 
+  {    
+    if (childFrame == child)
+       return count;
+
+    nsresult rv = childFrame->GetNextSibling(&childFrame);
+    NS_ASSERTION(rv == NS_OK,"failed to get next child");
+    count++;
+  }
+
+  return -1;
+}
+
+PRInt32
+nsFrameNavigator::CountFrames(nsIFrame* aFrame)
+{
+  PRInt32 count = 0;
+
+  nsIFrame* childFrame;
+  aFrame->FirstChild(nsnull, &childFrame); 
+  while (nsnull != childFrame) 
+  {    
+    nsresult rv = childFrame->GetNextSibling(&childFrame);
+    NS_ASSERTION(rv == NS_OK,"failed to get next child");
+    count++;
+  }
+
+  return count;
+}
+
+nsIFrame*
+nsFrameNavigator::GetChildAt(nsIFrame* parent, PRInt32 index)
+{
+  PRInt32 count = 0;
+
+  nsIFrame* childFrame;
+  parent->FirstChild(nsnull, &childFrame); 
+  while (nsnull != childFrame) 
+  {    
+    if (count == index)
+       return childFrame;
+
+    nsresult rv = childFrame->GetNextSibling(&childFrame);
+    NS_ASSERTION(rv == NS_OK,"failed to get next child");
+    count++;
+  }
+
+  return nsnull;
+}
+

layout/xul/base/src/nsFrameNavigator.h

@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "License"); you may not use this file except in
+ * compliance with the License.  You may obtain a copy of the License at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * The Original Code is Mozilla Communicator client code.
+ *
+ * The Initial Developer of the Original Code is Netscape Communications
+ * Corporation.  Portions created by Netscape are Copyright (C) 1998
+ * Netscape Communications Corporation.  All Rights Reserved.
+ */
+
+/**
+
+  Eric D Vaughan
+  This class lays out its children either vertically or horizontally
+ 
+**/
+
+#ifndef nsGrippyFrame_h___
+#define nsGrippyFrame_h___
+
+#include "nsIFrame.h"
+
+class nsFrameNavigator 
+{
+public:
+
+  static nsIFrame* GetChildBeforeAfter(nsIFrame* start, PRBool before);
+  static nsIFrame* GetChildAt(nsIFrame* parent, PRInt32 index);
+  static PRInt32 IndexOf(nsIFrame* parent, nsIFrame* child);
+  static PRInt32 CountFrames(nsIFrame* aFrame);
+  static nsIAtom* GetTag(nsIFrame* frame);
+
+}; 
+
+
+
+#endif
+