Flutter Core
What is Flutter and how does it differ from other cross-platform frameworks?
Flutter is Google's open-source UI toolkit that compiles to native ARM code and draws every pixel itself us...
10 XP3m
Flutter Core
25 questions
Widgets, lifecycle, rendering pipeline, build modes
Flutter Core
What is the difference between StatelessWidget and StatefulWidget?
StatelessWidget is immutable and rebuilds only when its parent provides new configuration; StatefulWidget o...
10 XP3m
Flutter Core
Explain the complete lifecycle of a StatefulWidget
The lifecycle goes: createState → initState → didChangeDependencies → build → (didUpdateWidget / setState →...
20 XP5m
Flutter Core
What is BuildContext and how does it work in Flutter?
BuildContext is a handle to a widget's location in the Element tree; it's how widgets access inherited data...
20 XP4m
Flutter Core
What is the difference between Hot Reload and Hot Restart?
Hot Reload injects updated Dart code into the running VM and calls build() again without resetting state; H...
10 XP2m
Flutter Core
What are Flutter's three build modes: Debug, Profile, and Release?
Debug uses JIT for fast iteration with hot reload; Profile mirrors release performance with profiling tools...
10 XP2m
Flutter Core
Explain Flutter's 3-tree rendering architecture: Widget, Element, and RenderObject
Flutter maintains three parallel trees: Widgets (immutable descriptions), Elements (mutable nodes that reco...
50 XP8m
Flutter Core
What are Keys in Flutter and when should you use them?
Keys help Flutter's reconciliation algorithm identify widgets when they move within the tree. Use LocalKeys...
30 XP5m
Flutter Core
How does InheritedWidget work and when should you use it?
InheritedWidget propagates data down the widget tree efficiently; descendants call context.dependOnInherite...
30 XP6m
Flutter Core
What are Platform Channels and how do you use them?
Platform Channels let Flutter communicate with native Android/iOS code using message-passing over MethodCha...
50 XP7m
Flutter Core
What is the difference between LocalKey and GlobalKey?
LocalKey (ValueKey, ObjectKey, UniqueKey) identifies a widget within its parent's children list; GlobalKey ...
20 XP3m
Flutter Core
What are Flutter's AppLifecycleState values and when do they trigger?
AppLifecycleState has four values: resumed (visible and active), inactive (visible but not focused, e.g., p...
20 XP3m
Flutter Core
What is vsync and TickerProvider in Flutter?
vsync is a TickerProvider that synchronizes animations to the display's refresh rate — preventing off-scree...
30 XP4m
Flutter Core
What tools are available in Flutter DevTools and when do you use them?
Flutter DevTools provides a Widget Inspector (tree visualization), Performance tab (frame timeline, jank de...
20 XP4m
Flutter Core
When would you use MaterialApp vs CupertinoApp vs WidgetsApp?
MaterialApp uses Google Material Design widgets; CupertinoApp uses Apple-style iOS widgets; WidgetsApp is t...
10 XP2m
Flutter Core
What is the difference between a Flutter package and a plugin?
A Flutter package is pure Dart code; a plugin is a package that also contains native platform code (Kotlin/...
10 XP2m
Flutter Core
What is Impeller and how does it differ from Skia?
Impeller is Flutter's new rendering engine that pre-compiles shaders at build time, eliminating shader comp...
50 XP5m
Flutter Core
Explain JIT vs AOT compilation in Dart/Flutter
JIT (Just-In-Time) compiles Dart at runtime in Debug mode, enabling hot reload but slower startup; AOT (Ahe...
30 XP3m
Flutter Core
What is the role of Scaffold and SafeArea in Flutter?
Scaffold provides the basic Material Design visual layout structure (AppBar, body, FAB, Drawer, BottomNavig...
10 XP2m
Flutter Core
What is the role of the Flutter Engine?
The Flutter Engine (written in C++) provides the Dart runtime, Skia/Impeller rendering pipeline, file I/O, ...
30 XP4m
Flutter Core
What is the mounted property and why is it important in async code?
mounted is a boolean on State that is true when the State is in the widget tree and false after dispose() i...
20 XP3m
Flutter Core
What is tree shaking in Flutter and how does it work?
Tree shaking is the Dart compiler's dead-code elimination pass during AOT release builds — it removes class...
20 XP2m
Flutter Core
Explain the structure of pubspec.yaml and key fields
pubspec.yaml is the Flutter/Dart project manifest defining package name, version, dependencies (pub.dev pac...
10 XP3m
Flutter Core
What is the role of main() and runApp() in a Flutter application?
main() is the Dart entry point; runApp() inflates the given widget as the root of the widget tree, initiali...
10 XP2m
Flutter Core
What is the difference between flutter run and flutter build for production?
flutter run starts the app in debug mode on a connected device/emulator; flutter build compiles the app for...
10 XP2m