didUpdateWidget method
- @mustCallSuper
- @protected
Called whenever the widget configuration changes.
If the parent widget rebuilds and request that this location in the tree
update to display a new widget with the same runtimeType and
Widget.key, the framework will update the widget property of this
State object to refer to the new widget and then call this method
with the previous widget as an argument.
Override this method to respond when the widget changes (e.g., to start implicit animations).
The framework always calls build after calling didUpdateWidget, which means any calls to setState in didUpdateWidget are redundant.
If a State's build method depends on an object that can itself change
state, for example a ChangeNotifier or Stream, or some other object to
which one can subscribe to receive notifications, then the State should
subscribe to that object during initState, unsubscribe from the old
object and subscribe to the new object when it changes in
didUpdateWidget, and then unsubscribe from the object in dispose.
If you override this, make sure your method starts with a call to super.didUpdateWidget(oldWidget).
Implementation
@mustCallSuper
@protected
void didUpdateWidget(covariant T oldWidget) { }