Answers for "flutter bottom sheet rounded corners"

flutter rounded bottom sheet

void startAddNewMoodCheckin(BuildContext ctx) {
    showModalBottomSheet(
        shape: RoundedRectangleBorder(		//the rounded corner is created here
          borderRadius: BorderRadius.circular(10.0),
        ),
        context: ctx,
        builder: (_) {
          return Container(
            child: Text("This is a modal sheet"),
          );
        });
  }

rounded button flutter

FlatButton(
              color: Colors.red,
              shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(18.0)),
              child: new Text('round button'),
              onPressed: () {},
            ),