Please check the below code. I have comment out the solution in code.
class Something extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( appBar: AppBar( title: const Text('Solve Before Downvote !'), ), body: Container( width: MediaQuery.of(context).size.width, color: Color(0xff263238), child: Column( mainAxisAlignment: MainAxisAlignment.center, crossAxisAlignment: CrossAxisAlignment.center, children: [ SingleChildScrollView( child: Center( child: Column( crossAxisAlignment: CrossAxisAlignment.center, children: [ MaterialButton( shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(10.0)), padding: EdgeInsets.only(left: 5), color: Colors.green, onPressed: () {}, child: Text('SomeThing', textAlign: TextAlign.left), ), MaterialButton( shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(10.0)), color: Colors.green, onPressed: () {}, child: Text('Nothing', textAlign: TextAlign.left), ), MaterialButton( shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(10.0)), color: Colors.green, onPressed: () {}, child: Text('Can You do something ?', textAlign: TextAlign.left), ), MaterialButton( shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(10.0)), color: Colors.green, onPressed: () {}, child: Text('Nothing to do !', textAlign: TextAlign.left), ), ], ), ), ) ], ), ), ); } }

[![enter image description here][1]][1]

[1]: https://i.stack.imgur.com/TszEp.gif
class RoundedButton extends StatelessWidget { @override Widget build(BuildContext context) { return Scaffold( floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat, floatingActionButton: SizedBox( height: 60.0, width: 250.0, child: Material( shape: StadiumBorder(), textStyle: Theme.of(context).textTheme.button, elevation: 6.0, child: Row( crossAxisAlignment: CrossAxisAlignment.center, mainAxisAlignment: MainAxisAlignment.spaceBetween, children: <Widget>[ Expanded( child: RaisedButton( elevation: 0.0, color: Colors.white, shape: new RoundedRectangleBorder( borderRadius: BorderRadius.horizontal(left: Radius.circular(50))), child: Padding( padding: const EdgeInsets.all(0.0), child: Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Icon( Icons.add, color: Colors.green, size: 30.0, ), Text("New Message") ], ), ), onPressed: () {}, ), ), Expanded( child: RaisedButton( elevation: 0.0, color: Colors.white, shape: new RoundedRectangleBorder( borderRadius: BorderRadius.horizontal(right: Radius.circular(50))), child: Padding( padding: const EdgeInsets.all(2.0), child: Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Icon( Icons.more_vert, color: Colors.green, size: 30.0, ), Text("More") ], ), ), onPressed: () {}, ), ), ], ), ), ), body: Container(), ); } }