StatefulWidget vs StatelessWidget: Which One to Use
Decide by whether the UI changes
StatelessWidget is a widget whose internal state doesn't change once built. Text, Icon, Container are typical examples.
StatefulWidget can update UI by calling setState(). Used for UI with user interaction: checkboxes, sliders, form inputs.
In modern Flutter, using state management libraries (Provider, Riverpod) to minimize StatefulWidget usage is recommended.
Implementation Steps
1
Determine if UI changes based on input → decide Stateless or Stateful
2
When using StatefulWidget, call setState() in State class
3
Initialize in initState(), release resources in dispose()
4
Replace with state management library to reduce StatefulWidget usage when possible
Pros
- ✓ StatelessWidget is lightweight and easy to test
- ✓ StatefulWidget is intuitive for local state management
Cons
- ✗ setState() rebuilds entire widget → performance caution
- ✗ Managing complex state with StatefulWidget alone makes code complex
Use Cases
Interactive UI: counters, toggles, form inputs
Information display cards, labels (StatelessWidget)