Answers for "how to add icon to MaterialButton() in flutter"

icon as button flutter

IconButton(
            icon: Icon(
              Icons.directions_transit,
            ),
            iconSize: 50,
            color: Colors.green,
            splashColor: Colors.purple,
            onPressed: () {},
          ),

flutter RaisedButton with icon

// JZ
Container(
                  height: 25.0,
                  padding: EdgeInsets.only(left: 10.0),
                  child: RaisedButton.icon(
                    color: Colors.white,
                    label: Text(
                      'Te amo, pero no eres para mi',
                      style: TextStyle(fontSize: 13.0),
                    ),
                    icon: Icon(
                      Icons.ac_unit_outlined,
                      size: 13.0,
                    ),
                    onPressed: () {},
                  ),
                )