## you can inspect the autosave code to see what it does.
%autosave??

profile_dir = ! ipython locate
profile_dir = profile_dir[0]
profile_dir

import os.path
custom_js_path = os.path.join(profile_dir,'profile_default','static','custom','custom.js')

#  my custom js
with open(custom_js_path) as f:
    for l in f: 
        print l,

%%javascript
var CellToolbar = IPython.CellToolbar
var toggle =  function(div, cell) {
     var button_container = $(div)

     // let's create a button that show the  current value of the metadata
     var button = $('<button/>').addClass('btn btn-mini').text(String(cell.metadata.foo));

     // On click, change the metadata value and update the button label
     button.click(function(){
                 var v = cell.metadata.foo;
                 cell.metadata.foo = !v;
                 button.text(String(!v));
             })

     // add the button to the DOM div.
     button_container.append(button);
}

 // now we register the callback under the name foo to give the
 // user the ability to use it later
 CellToolbar.register_callback('tuto.foo', toggle);

%%javascript
IPython.CellToolbar.register_preset('Tutorial 1',['tuto.foo','default.rawedit'])
IPython.CellToolbar.register_preset('Tutorial 2',['slideshow.select','tuto.foo'])

%load soln/celldiff.js