adding focus tracker

layout/base/public/nsIFocusTracker.h

@@ -0,0 +1,48 @@
+/* -*- 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 "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+#ifndef nsIFocusTracker_h___
+#define nsIFocusTracker_h___
+
+#include "nsISupports.h"
+#include "nsIFrame.h"
+   
+
+// IID for the nsIFocusTracker interface
+#define NS_IFOCUSTRACKER_IID  \
+{ 0x81ac51d1, 0x923b, 0x11d2, \
+  { 0x91, 0x8f, 0x0, 0x80, 0xc8, 0xe4, 0x4d, 0xb5 } }
+
+class nsIFocusTracker : public nsISupports
+{
+public:
+  /** SetFocus will keep track of the new frame as the focus frame. 
+   *  as well as keeping track of the anchor frame; <BR>
+   *  @param aFrame will be the focus frame
+   *  @param aAnchorFrame will be the anchor frame
+   */
+  virtual nsresult SetFocus(nsIFrame *aFrame, nsIFrame *aAnchorFrame) = 0;
+
+  /** GetFocus give the frame and the anchor frame.
+   *  @param aFrame will be the focus frame
+   *  @param aAnchorFrame will be the anchor frame
+   */
+  virtual nsresult GetFocus(nsIFrame **aFrame, nsIFrame **aAnchorFrame) = 0;
+};
+
+
+#endif //nsIFocusTracker_h___