Theme constructor

const Theme({Key key, @required ThemeData data, bool isMaterialAppTheme: false, @required Widget child })

Applies the given theme data to child.

The data and child arguments must not be null.

Implementation 

const Theme({
  Key key,
  @required this.data,
  this.isMaterialAppTheme = false,
  @required this.child,
}) : assert(child != null),
     assert(data != null),
     super(key: key);