What is the class in Flutter?

Widget class Null safety Widgets are the central class hierarchy in the Flutter framework . A widget is an immutable description of part of a user interface. Widgets can be inflated into elements, which manage the underlying render tree. Widgets themselves have no mutable state (all their fields must be final).

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How do you write setState in flutter?

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.

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