A stateful widget is dynamic: for example, it can change its appearance in response to events triggered by user interactions or when it receives data. Checkbox , Radio , Slider , InkWell , Form , and TextField are examples of stateful widgets. Stateful widgets subclass StatefulWidget .
Read moreWhen should I use stateful widget flutter?
Stateful widget are useful when the part of the user interface you are describing can change dynamically , e.g. due to having an internal clock-driven state, or depending on some system state.
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