classes property Null safety

CssClassSet classes
override

The set of CSS classes applied to this element.

This set makes it easy to add, remove or toggle the classes applied to this element.

element.classes.add('selected');
element.classes.toggle('isOnline');
element.classes.remove('selected');

Implementation

CssClassSet get classes => new AttributeClassSet(this);
void classes= (Iterable<String> value)
inherited

Implementation

set classes(Iterable<String> value) {
  // TODO(sra): Do this without reading the classes in clear() and addAll(),
  // or writing the classes in clear().
  CssClassSet classSet = classes;
  classSet.clear();
  classSet.addAll(value);
}