anchor.diff:    "selected or deselected, such as adding or removing an item's star.";
   
   const String _iconCode =
  -"""// Member variable holding toggle value
  -bool iconButtonToggle;
  -
  -// Toggable icon button
  +"""// Member variable holding toggle value.
  +bool value;
  +
  +// Toggleable icon button.
   new IconButton(
     icon: Icons.thumb_up,
     onPressed: () {
  -    setState(() => iconButtonToggle = !iconButtonToggle);
  +    setState(() => value = !value);
     },
  -  color: iconButtonToggle ? Theme.of(context).primaryColor : null
  +  color: value ? Theme.of(context).primaryColor : null
   )""";
   
   const String _actionText =
     "# Floating action buttons\n"
     "Floating action buttons are used for a promoted action. They are "
  -  "distinguished by a circled icon floating above the UI and have motion "
  +  "distinguished by a circled icon floating above the UI and can have motion "
     "behaviors that include morphing, launching, and a transferring anchor "
     "point.";
   
   const String _actionCode =
  -"""// Floating action button in Scaffold
  +"""// Floating action button in Scaffold.
   new Scaffold(
     appBar: new AppBar(
       title: new Text('Demo')
  
positive.code:   }
  );
  
  // Create a disabled button
  // The button is disabled because there is no
  // onPressed method specified
  new RaisedButton(
    child: new Text('BUTTON TITLE')
  );""";
  
  const String _flatText =
    "# Flat buttons\n"
    "A flat button is made of ink that displays ink reactions on press "
    "but does not lift. Use flat buttons on toolbars, in dialogs and "
    "inline with padding";
  
  const String _flatCode =
  """// Create a flat button
  new FlatButton(
    child: new Text('BUTTON TITLE'),
    onPressed: () {
  
negative.code:   }
  );
  
  // Create a disabled button.
  // Buttons are disabled when onPressed isn't
  // specified or is null.
  new FlatButton(
    child: new Text('BUTTON TITLE')
  );""";
  