CustomNavigationBar | An easy way to customize navigation bar in iOS | Navigation library

    class MyCustomBNavigation extends StatefulWidget {
      @override
      _MyCustomBNavigationState createState() => _MyCustomBNavigationState();
    }

    class _MyCustomBNavigationState extends State {
      int _currentIndex = 0;
      @override
      void initState() {
         pageController = PageController(
          initialPage: _currentIndex,
          keepPage: true,
        );
         super.initState();
       }

      @override
      Widget build(BuildContext context) {
        return Stack(
          children: [
            buildPageView(),
            Positioned(
                left: 0, right: 0, bottom: 0, child: _buildBottomNavigationBar()),
          ],
        );
      }

      Widget _buildBottomNavigationBar() {
        return _buildBlurEffect();
      }

      PageController pageController;

      final GlobalKey> orderFormKey = GlobalKey();

      void pageChanged(int index) {
        setState(() {
          _currentIndex = index;
        });
      }

      Widget buildPageView() {
        return PageView(
          key: orderFormKey,
          controller: pageController,
          onPageChanged: (index) {
            pageChanged(index);
          },
          children: [
          // You just need to replace your pages with this Container

            Container(child: Center(child: Text("First"))),
            Container(child: Center(child: Text("Second"))),
            Container(child: Center(child: Text("Third"))),
            Container(child: Center(child: Text("Fourth"))),
            Container(child: Center(child: Text("Fifth"))),
          ],
        );
      }

      Widget _buildBlurEffect() {
        return CustomNavigationBar(
          iconSize: 30.0,
          selectedColor: Colors.white,
          strokeColor: Colors.white12,
          unSelectedColor: Colors.grey[600],
          backgroundColor: Colors.black,
          borderRadius: Radius.circular(20.0),
          blurEffect: true,
          opacity: 0.8,
          items: [
            CustomNavigationBarItem(
              icon: Icon(Icons.star),
            ),
            CustomNavigationBarItem(
              icon: Icon(Icons.monetization_on),
            ),
            CustomNavigationBarItem(icon: Icon(Icons.star)),
            CustomNavigationBarItem(
              icon: Icon(Icons.monetization_on),
            ),
            CustomNavigationBarItem(
              icon: Icon(Icons.share),
            ),
          ],
          currentIndex: _currentIndex,
          onTap: (index) {
            setState(() {
              _currentIndex = index;
              setState(() {

                pageController.animateToPage(_currentIndex,
                    duration: Duration(milliseconds: 500), curve: Curves.linear);
              });
            });
          },
          isFloating: true,
        );
      }
    }