Index: src/genprops.awk
===================================================================
RCS file: /cvs/octave/src/genprops.awk,v
retrieving revision 1.10
diff -c -r1.10 genprops.awk
*** src/genprops.awk	12 Jan 2008 08:21:57 -0000	1.10
--- src/genprops.awk	13 Jan 2008 21:00:25 -0000
***************
*** 176,185 ****
  
  function emit_get_callback (i)
  {
!   printf ("  void execute_%s (void)", name[i]);
    
    if (emit_get[i] == "definition")
!     printf (" { %s.execute (); }\n", name[i]);
    else
      printf (";\n");
  
--- 176,185 ----
  
  function emit_get_callback (i)
  {
!   printf ("  void execute_%s (const octave_value& data = octave_value ()) const", name[i]);
    
    if (emit_get[i] == "definition")
!     printf (" { %s.execute (data); }\n", name[i]);
    else
      printf (";\n");
  
Index: src/graphics.cc
===================================================================
RCS file: /cvs/octave/src/graphics.cc,v
retrieving revision 1.69
diff -c -r1.69 graphics.cc
*** src/graphics.cc	13 Jan 2008 06:46:39 -0000	1.69
--- src/graphics.cc	13 Jan 2008 21:00:30 -0000
***************
*** 137,142 ****
--- 137,197 ----
    return retval;
  }
  
+ // NOTE: "cb" is passed by value, because "function_value" method
+ //       is non-const; passing "cb" by const-reference is not
+ //       possible
+ 
+ static void
+ execute_callback (octave_value cb, const graphics_handle& h,
+                   const octave_value& data)
+ {
+   octave_value_list args;
+   octave_function *fcn = 0;
+ 
+   args(0) = h.as_octave_value ();
+   args(1) = data;
+ 
+   BEGIN_INTERRUPT_WITH_EXCEPTIONS;
+ 
+   if (cb.is_function_handle ())
+     fcn = cb.function_value ();
+   else if (cb.is_string ())
+     {
+       std::string s = cb.string_value ();
+       octave_value f = symbol_table::find_function (s);
+       int status;
+ 
+       if (f.is_defined ())
+         fcn = f.function_value ();
+       else
+         {
+           eval_string (s, false, status);
+           return;
+         }
+     }
+   else if (cb.is_cell () && cb.length () > 0
+            && (cb.rows () == 1 || cb.columns () == 1)
+            && cb.cell_value ()(0).is_function_handle ())
+     {
+       Cell c = cb.cell_value ();
+ 
+       fcn = c(0).function_value ();
+       if (! error_state)
+         {
+           for (int i = 0; i < c.length () ; i++)
+             args(2+i) = c(i);
+         }
+     }
+   else
+     error ("trying to execute non-executable object (class = %s)",
+            cb.class_name ());
+ 
+   if (! error_state)
+     feval (fcn, args);
+   
+   END_INTERRUPT_WITH_EXCEPTIONS;
+ }
+ 
  // ---------------------------------------------------------------------
  
  radio_values::radio_values (const std::string& opt_string)
***************
*** 335,350 ****
  }
  
  bool
! callback_property::validate (const octave_value&) const
  {
!   // FIXME: implement this
!   return true;
  }
  
  void
! callback_property::execute (void)
  {
!   // FIXME: define correct signature and implement this
  }
  
  // ---------------------------------------------------------------------
--- 390,423 ----
  }
  
  bool
! callback_property::validate (const octave_value& v) const
  {
!   // case 1: function handle
!   // case 2: cell array with first element being a function handle
!   // case 3: string corresponding to known function name
!   // case 4: evaluatable string
!   // case 5: empty matrix
! 
!   if (v.is_function_handle ())
!     return true;
!   else if (v.is_string ())
!     // complete validation will be done at execution-time
!     return true;
!   else if (v.is_cell () && v.length () > 0
!            && (v.rows() == 1 || v.columns () == 1)
!            && v.cell_value ()(0).is_function_handle ())
!     return true;
!   else if (v.is_empty ())
!     return true;
! 
!   return false;
  }
  
  void
! callback_property::execute (const octave_value& data) const
  {
!   if (callback.is_defined () && ! callback.is_empty ())
!     execute_callback (callback, get_parent (), data);
  }
  
  // ---------------------------------------------------------------------
***************
*** 606,611 ****
--- 679,686 ----
  
  	  if (p != handle_map.end ())
  	    {
+               p->second.get_properties ().execute_deletefcn ();
+ 
  	      handle_map.erase (p);
  
  	      if (h.value () < 0)
***************
*** 2065,2073 ****
  
  	      graphics_object parent_obj = gh_manager::get_object (parent_h);
  
! 	      parent_obj.remove_child (h);
  
  	      gh_manager::free (h);
  	    }
  	  else
  	    error ("delete: invalid graphics object (= %g)", val);
--- 2140,2152 ----
  
  	      graphics_object parent_obj = gh_manager::get_object (parent_h);
  
!               // NOTE: free the handle before removing it from its parent's
!               //       children, such that the object's state is correct when
!               //       the deletefcn callback is executed
  
  	      gh_manager::free (h);
+ 
+ 	      parent_obj.remove_child (h);
  	    }
  	  else
  	    error ("delete: invalid graphics object (= %g)", val);
Index: src/graphics.h.in
===================================================================
RCS file: /cvs/octave/src/graphics.h.in,v
retrieving revision 1.32
diff -c -r1.32 graphics.h.in
*** src/graphics.h.in	13 Jan 2008 06:46:39 -0000	1.32
--- src/graphics.h.in	13 Jan 2008 21:00:31 -0000
***************
*** 796,802 ****
                 get_name ().c_str ());
      }
  
!   OCTINTERP_API void execute (void);
  
    callback_property& operator = (const octave_value& val)
      {
--- 796,802 ----
                 get_name ().c_str ());
      }
  
!   OCTINTERP_API void execute (const octave_value& data = octave_value ()) const;
  
    callback_property& operator = (const octave_value& val)
      {
***************
*** 967,983 ****
        parent ("parent", mh, p), 
        children (),
        busyaction ("parent", mh, "{queue}|cancel"),
!       buttondownfcn ("buttondownfcn", mh, octave_value ()),
        clipping ("clipping", mh, true),
!       createfcn ("createfcn" , mh, octave_value ()),
!       deletefcn ("deletefcn", mh, octave_value ()),
        handlevisibility ("handlevisibility", mh, "{on}|callback|off"),
        hittest ("hittest", mh, true),
        interruptible ("interruptible", mh, true),
        selected ("selected", mh, false),
        selectionhighlight ("selectionhighlight", mh, true),
        uicontextmenu ("uicontextmenu", mh, graphics_handle ()),
!       userdata ("userdata", mh, octave_value ()),
        visible ("visible", mh, true)
      { }
  
--- 967,983 ----
        parent ("parent", mh, p), 
        children (),
        busyaction ("parent", mh, "{queue}|cancel"),
!       buttondownfcn ("buttondownfcn", mh, Matrix ()),
        clipping ("clipping", mh, true),
!       createfcn ("createfcn" , mh, Matrix ()),
!       deletefcn ("deletefcn", mh, Matrix ()),
        handlevisibility ("handlevisibility", mh, "{on}|callback|off"),
        hittest ("hittest", mh, true),
        interruptible ("interruptible", mh, true),
        selected ("selected", mh, false),
        selectionhighlight ("selectionhighlight", mh, true),
        uicontextmenu ("uicontextmenu", mh, graphics_handle ()),
!       userdata ("userdata", mh, Matrix ()),
        visible ("visible", mh, true)
      { }
  
***************
*** 1025,1032 ****
--- 1025,1038 ----
  
    std::string get_clipping (void) const { return clipping.current_value (); }
  
+   void execute_createfcn (const octave_value& data = octave_value ()) const
+     { createfcn.execute (data); }
+ 
    octave_value get_createfcn (void) const { return createfcn.get (); }
  
+   void execute_deletefcn (const octave_value& data = octave_value ()) const
+     { deletefcn.execute (data); }
+ 
    octave_value get_deletefcn (void) const { return deletefcn.get (); }
  
    std::string get_handlevisibility (void) const { return handlevisibility.current_value (); }