Add all classes specified in iterable
to element.
add and addAll are the Dart equivalent of jQuery's addClass.
Each element of iterable
must be a valid 'token' representing a single class, i.e. a non-empty string containing no whitespace.
void addAll(Iterable<String> iterable);
© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dart.dev/stable/2.5.0/dart-html/CssClassSet/addAll.html