Flutter Stateful Widgets
Stateful widgets are useful when the part of the user interface you are describing can change dynamically. User interfaces need to respond to a variety of things:
The user doing something in the user interface.
Receiving data from another computer.
This is what Stateful Widgets are for. They store data (state) in a associated State class and they can respond when that data (state) changes as the result of the user doing something.