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Stateless Vs Stateful Widgets

Whats what and what are they really? Stateless Widgets and Stateful Widget explained.


In a line, if your widget change appearance use stateful widget and if it doesn't use stateless widget that's all.

We know that flutter is all about widgets and in flutter there are 2 types of widgets.
  1. Stateless Widget
  2. Stateful Widget

Stateless Widget

A stateless widget never changes. For example Icon, IconButton, Text and so on. Once they are built they remain the same during the lifetime of the application.

There are various places where you might want to use Stateless widget such as your app Title, Images, and so on.

Stateful Widget

A stateful widget is something which has a state so basically that widget needs to be rebuilt whenever some event occurs. A good example would be a toggle button. Whenever you tap on the toggle button its state changes to either on or off. The appearance of the button changes and this happens because the stateful widget asks the build method to rebuild the widget and change its state.


Shortcut to create a stateless widget : type stless and let the autocomplete complete itself. 
Shortcut to create a stateful widget : type stful and let the autocomplete complete itself.


Sample Stateless Widget Code: 
class WidgetName extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      
    );
  }
}


Sample Stateful Widget Code:
class WidgetName extends StatefulWidget {
  @override
  _WidgetNameState createState() => _WidgetNameState();
}

class _WidgetNameState extends State<WidgetName> {
  @override
  Widget build(BuildContext context) {
    return Container(
      
    );
  }
}


For more, Stay Tuned! We will be posting a lot more informative posts about flutter. And if you missed, go ahead and look at Text Widget In Depth - Flutter  for an in-depth review about text widget.

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