Buttons Rounded

RaisedButton(
    onPressed: () {},
    color: Colors.amber,
    shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
    child: Text("Click This"),
  );

  FlatButton(
    onPressed: () {},
    color: Colors.amber,
    shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
    child: Text("Click This"),
  );

  GestureDetector(
    onTap: () {},
    child: Container(
      width: 100,
      decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(20), color: Colors.blue),
      child: Padding(
        padding: const EdgeInsets.all(8.0),
        child: Text(
          "Click",
          textAlign: TextAlign.center,
        ),
      ),
    ),
  );

  RaisedButton(
    onPressed: () {},
    color: Colors.amber,
    shape: RoundedRectangleBorder(
        side: BorderSide(color: Colors.red, width: 2),
        borderRadius: BorderRadius.circular(10)),
    child: Text("Click This"),
  );