Tag: Why do you need to call setState (() }) in a StatefulWidget when changing some internal data )?

According to Flutter’s official website, which is the very first resource for learning about anything Flutter, ” a Stateless widget is a widget that describes part of the user interface by building a constellation of other widgets that describe the user interface more concretely “.

1 Answer. You will need transform your “Container” in a custom statefull widget and then make his state management by your needs. Take a look at BLoC pattern here . With this pattern you will be able to update a specific widget in all widget tree without recreate all widgets.

In the onPressed event of the “Add Item” button, we add a new item then call setState in order to rebuild WidgetA and all it’s inner widgets , including WidgetB: onPressed: () => setState(() { items.

Update State In Flutter

setState is a way to dynamically change the UI . We call it inside the State Object class of the StatefulWidget. Calling setState marks the corresponding Widget dirty .20 Haz 2021