animated-bottom-navigation-bar

AnimatedBottomNavigationBar is a customizable widget inspired by dribble shot.

Getting Started

To get started, place your AnimatedBottomNavigationBar in the bottomNavigationBar slot of a Scaffold.
The AnimatedBottomNavigationBar respects FloatingActionButton location.
For example:

Scaffold(
   body: Container(), //destination screen
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.center,
      notchSmoothness: NotchSmoothness.verySmoothEdge,
      leftCornerRadius: 32,
      rightCornerRadius: 32,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-cornered-notched-bar

Customization

AnimatedBottomNavigationBar is customizable and works with 2, 3, 4, or 5 navigation elements.

Scaffold(
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-plain-bar

Scaffold(
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      leftCornerRadius: 32,
      rightCornerRadius: 32,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-cornered-bar

Scaffold(
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.endDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.end,
      notchSmoothness: NotchSmoothness.defaultEdge,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-notched-end

Scaffold(
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.center,
      notchSmoothness: NotchSmoothness.defaultEdge,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-default-notch-center

Scaffold(
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.center,
      notchSmoothness: NotchSmoothness.softEdge,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-soft-notch-center

Scaffold(
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.center,
      notchSmoothness: NotchSmoothness.smoothEdge,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-smooth-notch-center

Scaffold(
   floatingActionButton: FloatingActionButton(
      //params
   ),
   floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
   bottomNavigationBar: AnimatedBottomNavigationBar(
      icons: iconList,
      activeIndex: _bottomNavIndex,
      gapLocation: GapLocation.center,
      notchSmoothness: NotchSmoothness.verySmoothEdge,
      onTap: (index) => setState(() => _bottomNavIndex = index),
      //other params
   ),
);

example-very-smooth-notch-center

Driving Navigation Bar Changes

You have to change the active navigation bar tab programmatically by passing a new activeIndex to the AnimatedBottomNavigationBar widget.

class _MyAppState extends State<MyApp> {
  int activeIndex;

  /// Handler for when you want to programmatically change
  /// the active index. Calling `setState()` here causes
  /// Flutter to re-render the tree, which `AnimatedBottomNavigationBar`
  /// responds to by running its normal animation.
  void _onTap(int index) {
    setState((){
      activeIndex = index;
    });
  }

  Widget build(BuildContext context) {
    return AnimatedBottomNavigationBar(
      activeIndex: activeIndex,
      onTap: _onTap,
      //other params
    );
  }
}

GitHub