🔹 Flutter Basics (1–20)
1. What is Flutter?
Flutter is an open-source UI toolkit by Google used to build natively compiled applications for mobile, web, and desktop from a single codebase.
2. Which language is used in Flutter?
Flutter uses Dart programming language.
3. What is Dart?
Dart is an object-oriented, class-based programming language optimized for building UI.
4. What are widgets in Flutter?
Widgets are the basic building blocks of Flutter UI.
5. Types of widgets in Flutter?
- StatelessWidget
- StatefulWidget
6. What is StatelessWidget?
A widget that does not change its state after creation.
7. What is StatefulWidget?
A widget that can change its state during runtime.
8. What is Hot Reload?
It allows instant UI updates without restarting the app.
9. What is Hot Restart?
Restarts the app and resets the state.
10. What is Flutter SDK?
A set of tools to develop Flutter applications.
11. What platforms does Flutter support?
Android, iOS, Web, Windows, macOS, Linux.
12. What is BuildContext?
It represents the location of a widget in the widget tree.
13. What is Scaffold?
Provides basic app structure like AppBar, Body, Drawer.
14. What is MaterialApp?
Root widget that applies Material Design.
15. What is Cupertino?
Widgets that follow iOS-style design.
16. What is pubspec.yaml?
Configuration file for dependencies and assets.
17. What is main() function?
Entry point of Flutter app.
18. What is runApp()?
Starts the Flutter app.
19. What is widget tree?
Hierarchy of widgets in Flutter.
20. What is immutable widget?
Widgets that cannot change once created.
🔹 Layout & UI (21–40)
21. What is Container widget?
Used for styling, padding, margin, decoration.
22. Difference between Row and Column?
Row → horizontal layout
Column → vertical layout
23. What is Expanded widget?
Fills available space.
24. What is Flexible widget?
Controls how child occupies space.
25. What is Stack widget?
Overlaps widgets on top of each other.
26. What is Padding widget?
Adds internal spacing.
27. What is Align widget?
Aligns child widget.
28. What is MediaQuery?
Gets screen size and orientation.
29. What is ListView?
Scrollable list of widgets.
30. Types of ListView?
- ListView.builder
- ListView.separated
- ListView.custom
31. What is GridView?
Displays items in grid layout.
32. What is SingleChildScrollView?
Makes widget scrollable.
33. What is SafeArea?
Avoids system UI overlaps.
34. What is AspectRatio?
Maintains widget aspect ratio.
35. What is SizedBox?
Creates fixed-size box.
36. What is Card widget?
Material design card UI.
37. What is Divider?
Creates horizontal/vertical line.
38. What is InkWell?
Detects tap with ripple effect.
39. What is GestureDetector?
Detects gestures like tap, swipe.
40. Difference between InkWell & GestureDetector?
InkWell provides ripple effect, GestureDetector doesn’t.
🔹 State Management (41–60)
41. What is state in Flutter?
Data that can change during app lifecycle.
42. What is setState()?
Updates UI when state changes.
43. When to use setState()?
For small and local state changes.
44. What is Provider?
Popular state management solution.
45. What is Riverpod?
Improved version of Provider.
46. What is BLoC?
Business Logic Component pattern.
47. What is Cubit?
Simpler version of BLoC.
48. What is GetX?
Lightweight state management & routing.
49. What is Redux?
Predictable state container.
50. Which state management is best?
Depends on app complexity.
51. What is inheritedWidget?
Passes data down widget tree.
52. What is ChangeNotifier?
Notifies listeners about state changes.
53. What is Consumer widget?
Listens to Provider changes.
54. What is FutureBuilder?
Builds UI from Future data.
55. What is StreamBuilder?
Builds UI from stream data.
56. Difference between Future & Stream?
Future → one-time data
Stream → continuous data
57. What is async/await?
Handles asynchronous code.
58. What is isolate?
Runs code in parallel.
59. What is compute() function?
Runs heavy tasks in background.
60. What is state lifting?
Moving state to parent widget.
🔹 Navigation, API & Storage (61–80)
61. What is Navigator?
Manages app routing.
62. Types of navigation?
- Named routes
- Anonymous routes
63. What is push()?
Navigates to next screen.
64. What is pop()?
Returns to previous screen.
65. What is REST API?
Web service for data exchange.
66. Which package is used for API calls?
http, dio
67. What is JSON?
JavaScript Object Notation.
68. How to parse JSON in Flutter?
Using dart:convert
69. What is Model class?
Represents API data structure.
70. What is shared_preferences?
Stores small local data.
71. What is SQLite?
Local relational database.
72. What is Hive?
Fast NoSQL database.
73. What is Firebase?
Backend-as-a-service by Google.
74. Firebase services used in Flutter?
Auth, Firestore, Storage, Messaging
75. What is authentication?
User login verification.
76. What is token-based authentication?
Uses token for secure access.
77. What is pagination?
Loading data page by page.
78. What is pull-to-refresh?
Refresh content by swiping down.
79. What is caching?
Storing data for faster access.
80. What is offline support?
App works without internet.
🔹 Advanced & Miscellaneous (81–100)
81. What is plugin in Flutter?
Platform-specific functionality.
82. What is method channel?
Communicates with native code.
83. What is platform-specific code?
Android (Kotlin/Java), iOS (Swift)
84. What is Flutter Inspector?
Debug UI issues.
85. What is DevTools?
Performance & debugging tools.
86. What is tree shaking?
Removes unused code.
87. What is const keyword?
Creates compile-time constants.
88. What is final keyword?
Variable assigned once.
89. Difference between const & final?
const → compile-time
final → runtime
90. What is null safety?
Prevents null reference errors.
91. What is late keyword?
Delays variable initialization.
92. What is sound null safety?
Strict null safety enforcement.
93. What is widget testing?
Testing UI components.
94. What is unit testing?
Testing individual functions.
95. What is integration testing?
Testing full app flow.
96. What is build() method?
Returns widget UI.
97. What is mounted property?
Checks widget existence.
98. What is dispose() method?
Cleans resources.
99. What is lifecycle of StatefulWidget?
createState → initState → build → dispose
100. Why choose Flutter?
Fast development, single codebase, high performance.
