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.
Read moreWhat is key flutter?
Flutter commonly uses keys when it needs to uniquely identify specific widgets within a collection . Using keys also helps Flutter preserve the state of StatefulWidget s while they’re being replaced with other widgets or just moved in the widget tree.
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