valueListenable property

  1. @override
ValueListenable<T?> valueListenable
inherited

get value listenable

same as widget's onChanged , but it is more useful when you want to build a widget relies on field's value change

eg: if you want to build a clear icon on textField , but don't want to display it when textField's value is empty ,you can do like this :

 return ValueListenableBuilder<String?>(
        valueListenable:formeKey.valueField(name).valueListenable,
        builder: (context, a, b) {
          return a == null || a.length == 0
              ? SizedBox()
              : IconButton(icon:Icon(Icons.clear),onPressed:(){
                formeKey.valueField(name).value = '';
              });
        });

this notifier is used for ValueListenableBuilder

Implementation

@override
ValueListenable<T> get valueListenable => _delegate.valueListenable;