Circle background with navigation bar item's active state flutter

Solution 1:

One way is by checking the index and changing the color of the container accordingly.

eg : here index store the current screen index

BottomNavigationBarItem(
        icon: Container(
          decoration: BoxDecoration(
              color: index == 0 ? Colors.orange : Colors.transparent,
              shape: BoxShape.circle),
          child: Padding(
            padding: const EdgeInsets.all(8.0),
            child: Icon(Icons.ac_unit),
          ),
        ),
        title: Text(
          "Home",
          style: TextStyle(
            fontWeight: FontWeight.w700,
            fontFamily: 'Inter',
            fontSize: _sizeConfig.textSize(
              context,
              1.7,
            ),
          ),
        ),
      ),