setState method Null safety Notify the framework that the internal state of this object has changed. Whenever you change the internal state of a State object, make the change in a function that you pass to setState: setState(() { _myState = newValue; }); The provided callback is immediately called synchronously.
Read moreHow do you rebuild a stateful widget flutter?
The solution is to pass a new Key to WidgetB every time we need it to be rebuilt : WidgetA will see that WidgetB has changed and will rebuild it when setState is called. In other words, whenever a stateful widget’s Key property changes, calling setState on its parent will force a rebuild of the stateful widget.
Read moreHow do you refresh current state in flutter?
Force Flutter navigator to reload state when popping
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