RaisedButton({Key key, @required VoidCallback onPressed, Color color, Color disabledColor, int elevation: 2, int highlightElevation: 8, int disabledElevation: 0, Brightness colorBrightness, Widget child })

Creates a raised button.

The child argument is required and is typically a Text widget in all caps.

Source 

RaisedButton({
  Key key,
  @required this.onPressed,
  this.color,
  this.disabledColor,
  this.elevation: 2,
  this.highlightElevation: 8,
  this.disabledElevation: 0,
  this.colorBrightness,
  this.child
}) : super(key: key);