use colors.

06-raise-button-06-colors-use.dart

Widget _colorsButton() => Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          SizedBox(height: 10),
          RaisedButton(
            onPressed: () {
              print("click");
            },
            child: Text(
              "color:PURPLE\ntextColor: Colors.white\nhighlightColor: RED\nsplashColor: BLUE_DEEP",
              style: TextStyle(fontSize: 40),
            ),
            color: PURPLE,
            textColor: Colors.white,
            highlightColor: RED,
            splashColor: BLUE_DEEP,
          ),
          SizedBox(height: 10),
          RaisedButton(
            onPressed: null,
            child: Text(
              " onPressed: null \ndisabledColor: YELLOW,\n disabledTextColor: TEXT_BLACK,",
              style: TextStyle(fontSize: 40),
            ),
            disabledColor: YELLOW,
            disabledTextColor: TEXT_BLACK,
          ),
        ],
      );