shape: RoundedRectangleBorder( borderRadius: BorderRadius.circular(18.0), side: BorderSide(color: Colors.red) ),
borderRadius: BorderRadius.all(Radius.circular(5.0))
RaisedButton( shape: StadiumBorder(), onPressed: () {}, child: Text("Button"),)
Padding( padding: EdgeInsets.only(left: 150.0, right: 0.0), child: RaisedButton( textColor: Colors.white, color: Colors.black, child: Text("Search"), onPressed: () {}, shape: new RoundedRectangleBorder( borderRadius: new BorderRadius.circular(30.0), ), ),)