anchor.diff:        displayWhenEmpty: 'Friends', // 还有这种friend?
         tabLabel: 'Friends',
         icon: Icons.add,
  -      information: "You can view your friends' information or "
  -          "add new friends in this page.",);
  +      information: "Add friend",);
       _kata = new _Page(
         displayWhenEmpty: 'Kata',
         tabLabel: 'Kata',
         icon: Icons.add_box,
  -      information: "You can view or add katas here, and preview them.\n"
  -          "submitting is not supported ATM",);
  +      information: "Add Kata",);
       _me = new _Page(
         displayWhenEmpty: 'User not set yet.',
         tabLabel: 'Me',
  
positive.code:       floatingActionButton: !_selectedPage.fabHere ? null
            : new FloatingActionButton(
            key: _selectedPage.fabKey,
            tooltip: 'Show explanation',
            backgroundColor: _selectedPage.fabColor,
            child: _selectedPage.createIcon,
            onPressed: _selectedPage.onClick ?? _showExplanatoryText),
  
negative.code:             });
          }
        },
        information: "Refresh",);
      _allPages = <_Page>[_friends, _kata, _me];
      _tabController = new TabController(vsync: this, length: _allPages.length);
      _tabController.addListener(_handleTabSelection);
  