20 Android SDK Quiz Questions and Answers

Question 1:
What is the primary purpose of the AndroidManifest.xml file in an Android project?
A) To define the app’s UI layout
B) To declare components like activities, services, and permissions
C) To store user data
D) To handle network requests

Answer: B) To declare components like activities, services, and permissions

Explanation: The AndroidManifest.xml file is essential for defining the app’s structure, including its components, permissions, and other metadata, which the system uses to manage the app.

Question 2:
Which lifecycle method is called when an activity is first created?
A) onStart()
B) onResume()
C) onCreate()
D) onPause()

Answer: C) onCreate()

Explanation: onCreate() is the initial method in the activity lifecycle where you initialize the app’s state, such as setting up the UI and binding data.

Question 3:
What is the role of an Intent in Android?
A) To manage database operations
B) To facilitate communication between components, like starting an activity
C) To handle user interface elements
D) To process background tasks

Answer: B) To facilitate communication between components, like starting an activity

Explanation: Intents act as messaging objects that allow different Android components to request actions from one another, enabling features like navigation and data passing.

Question 4:
Which layout manager arranges views in a single column or row?
A) RelativeLayout
B) LinearLayout
C) FrameLayout
D) ConstraintLayout

Answer: B) LinearLayout

Explanation: LinearLayout organizes child views either horizontally or vertically in a single line, making it ideal for simple, sequential UI designs.

Question 5:
What does the View class represent in Android?
A) A background service
B) A basic building block for UI elements
C) A data storage mechanism
D) A network handler

Answer: B) A basic building block for UI elements

Explanation: The View class is the base for all UI components, handling drawing and event interactions to create the visual interface of an app.

Question 6:
Which permission is required to access the device’s location?
A) INTERNET
B) READ_CONTACTS
C) ACCESS_FINE_LOCATION
D) WRITE_EXTERNAL_STORAGE

Answer: C) ACCESS_FINE_LOCATION

Explanation: ACCESS_FINE_LOCATION grants the app access to precise GPS location data, ensuring user privacy by requiring explicit permission.

Question 7:
What is the purpose of a Fragment in Android?
A) To handle network calls
B) To represent a modular section of a UI that can be reused
C) To manage app-wide themes
D) To store persistent data

Answer: B) To represent a modular section of a UI that can be reused

Explanation: Fragments allow you to divide an activity into reusable UI components, improving flexibility for different screen sizes and orientations.

Question 8:
Which method is used to start a service in Android?
A) startActivity()
B) startService()
C) bindService()
D) stopService()

Answer: B) startService()

Explanation: startService() initiates a service to perform long-running operations in the background, separate from the UI thread.

Question 9:
What is SharedPreferences used for?
A) To store large databases
B) To save simple key-value pairs of data
C) To handle file I/O operations
D) To manage app permissions

Answer: B) To save simple key-value pairs of data

Explanation: SharedPreferences provides a straightforward way to store and retrieve small amounts of primitive data, like user settings, without a full database.

Question 10:
Which component is responsible for handling broadcast messages in Android?
A) Activity
B) BroadcastReceiver
C) Service
D) ContentProvider

Answer: B) BroadcastReceiver

Explanation: A BroadcastReceiver listens for system or app events, such as battery changes, and triggers actions in response.

Question 11:
What does the onDestroy() method signify in an activity’s lifecycle?
A) The activity is starting
B) The activity is being paused
C) The activity is being completely destroyed
D) The activity is resuming

Answer: C) The activity is being completely destroyed

Explanation: onDestroy() is called when the activity is finishing, allowing for cleanup of resources before the activity is removed from memory.

Question 12:
Which API level introduced the ConstraintLayout?
A) API 21
B) API 25
C) API 19
D) API 28

Answer: B) API 25

Explanation: ConstraintLayout was introduced in API 25 as part of the Android Support Library, providing a flexible way to create responsive UIs.

Question 13:
What is the main benefit of using RecyclerView over ListView?
A) Simpler code for basic lists
B) Better performance with large datasets and customizable layouts
C) Automatic data persistence
D) Built-in networking capabilities

Answer: B) Better performance with large datasets and customizable layouts

Explanation: RecyclerView offers efficient recycling of views and advanced features like item animations, making it superior for dynamic lists.

Question 14:
Which class is used for asynchronous HTTP requests in Android?
A) HttpURLConnection
B) SQLiteOpenHelper
C) MediaPlayer
D) TelephonyManager

Answer: A) HttpURLConnection

Explanation: HttpURLConnection provides a way to send and receive data over HTTP in the background, supporting modern networking needs.

Question 15:
What is the purpose of the onRequestPermissionsResult() method?
A) To handle activity results
B) To process the result of a permission request
C) To start a new activity
D) To save data

Answer: B) To process the result of a permission request

Explanation: This method is called after the user responds to a runtime permission request, allowing the app to check if permission was granted.

Question 16:
Which storage option is suitable for structured data like tables and queries?
A) SharedPreferences
B) Internal Storage
C) Room Database
D) External Storage

Answer: C) Room Database

Explanation: Room is an abstraction layer over SQLite that provides an easy way to work with relational databases in Android apps.

Question 17:
What does the setContentView() method do?
A) Sets the app’s theme
B) Loads the layout XML into the activity
C) Starts a new intent
D) Handles user clicks

Answer: B) Loads the layout XML into the activity

Explanation: setContentView() inflates the specified layout resource and associates it with the activity’s UI.

Question 18:
Which attribute in AndroidManifest.xml defines the main entry point activity?
A) android:theme
B) android:label
C) android.intent.action.MAIN
D) android:versionCode

Answer: C) android.intent.action.MAIN

Explanation: The android.intent.action.MAIN category, combined with android.intent.category.LAUNCHER, marks an activity as the app’s launcher.

Question 19:
What is the function of the ViewModel class in Android architecture?
A) To handle direct UI drawing
B) To store and manage UI-related data across configuration changes
C) To process network requests
D) To manage permissions

Answer: B) To store and manage UI-related data across configuration changes

Explanation: ViewModel survives configuration changes like screen rotations, helping maintain data without recreating it.

Question 20:
Which tool is used to build and package Android apps?
A) ADB (Android Debug Bridge)
B) Gradle
C) Git
D) Emulator

Answer: B) Gradle

Explanation: Gradle is the build system used in Android projects to compile code, manage dependencies, and create APK files.