didUpdateWidget() This method is helpful to unsubscribe the old object and subscribe to new one if it is required for the object to be replaced with updated widget configuration. Overriding this method responds when the widget changes (example, to begin implicit animations).
Read moreWhat is createState () in flutter?
createState method Null safety Creates the mutable state for this widget at a given location in the tree . Subclasses should override this method to return a newly created instance of their associated State subclass: @override State<MyWidget> createState() => _MyWidgetState();
Read moreWhat is a stateful widget?
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.
Read moreHow do I rebuild a stateful widget?
The solution is to pass a new Key to WidgetB every time we need it to be rebuilt : WidgetA will see that WidgetB has changed and will rebuild it when setState is called. In other words, whenever a stateful widget’s Key property changes, calling setState on its parent will force a rebuild of the stateful widget.12 Tem 2021
Read moreWhy is the build () method on state and not stateful widget?
Why is the build method on State, and not StatefulWidget? Putting a Widget build(BuildContext context) method on State rather than putting a Widget build(BuildContext context, State state) method on StatefulWidget gives developers more flexibility when subclassing StatefulWidget .
Read moreDoes a new state object is created if the widget rebuild?
The tldr version is that State objects are long lived, but StatefulWidget s (and all Widget subclasses) are thrown away and rebuilt whenever configuration changes .
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