Q-1: MCQ/Short Question/Fill in the Blanks (Any Five) - Section I (5 Marks)

Questions

i) What is the function of the android SDK?
ii) What is the full form of AVD?
iii) Define the given android terminology - activity.
iv) What is the use of manifest file in android?
v) What is difference between view and viewgroup?
vi) How to use tab layout in Android?
vii) Write difference between emulator and simulators.

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Answers

i) Function of Android SDK

The Android SDK (Software Development Kit) serves several critical functions:

Primary Functions:

• Development Tools: Provides essential tools for Android app development
• API Libraries: Contains Android API libraries for different Android versions
• Debugging Tools: Includes debugging and profiling tools
• Build Tools: Provides compilation and packaging tools
• Documentation: Comprehensive documentation and code samples

Key Components:

1. Android Debug Bridge (ADB): Command-line tool for device communication
2. Android Emulator: Virtual device for testing applications
3. DDMS: Dalvik Debug Monitor Server for debugging
4. Build Tools: Tools for compiling and packaging apps
5. Platform Tools: Essential command-line tools
6. SDK Manager: Tool to download and manage SDK components

Functions:

• App Development: Create, compile, and package Android applications
• Testing: Test apps on virtual and real devices
• Debugging: Debug applications and monitor performance
• Deployment: Deploy apps to devices and app stores
• API Access: Access Android platform APIs and services

ii) Full Form of AVD

AVD stands for Android Virtual Device.

What is AVD:

• Virtual Emulator: Software emulation of Android device
• Testing Platform: Used for testing apps without physical hardware
• Configuration Tool: Allows custom device configurations
• Development Aid: Essential tool for Android development

Key Features:

• Simulates different Android versions
• Configurable hardware specifications
• Various screen sizes and resolutions
• Network and sensor simulation

iii) Android Terminology - Activity

Definition:

An Activity is a fundamental Android component that represents a single screen with a user interface.

Key Characteristics:

• Single Screen: Represents one screen of the app
• User Interface: Contains UI elements and handles user interactions
• Lifecycle Management: Has well-defined lifecycle states
• Intent-based: Can be started by Intents
• Stack Management: Managed in activity stack

Activity Lifecycle States:

1. Created: Activity is being created
2. Started: Activity becomes visible
3. Resumed: Activity is in foreground and interactive
4. Paused: Activity is partially obscured
5. Stopped: Activity is not visible
6. Destroyed: Activity is being destroyed

Example:

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

iv) Use of Manifest File in Android

The AndroidManifest.xml file serves multiple critical purposes:

Primary Uses:

1. Application Declaration: Declares application components
2. Permissions: Specifies required permissions
3. API Level: Defines minimum and target SDK versions
4. Components Registration: Registers activities, services, receivers
5. Intent Filters: Defines how components respond to intents

Key Elements:

<manifest xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-permission android:name="android.permission.INTERNET" />
    
    <application android:label="@string/app_name">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

Functions:

• Security: Controls app permissions and access
• System Integration: Tells system about app components
• Configuration: App-wide configuration settings
• Metadata: Application metadata and information

v) Difference between View and ViewGroup

Aspect	View	ViewGroup
Definition	Basic UI building block	Container for other views
Purpose	Display content and handle interactions	Organize and layout child views
Inheritance	Extends View class directly	Extends ViewGroup (which extends View)
Children	Cannot contain other views	Can contain multiple child views
Examples	TextView, Button, ImageView, EditText	LinearLayout, RelativeLayout, FrameLayout
Functionality	Specific UI tasks	Layout management and positioning
Rendering	Draws specific content	Manages child view positioning
Interaction	Direct user interaction	Indirect through child views

View Characteristics:

• Atomic: Cannot be subdivided
• Interactive: Handles touch events
• Drawable: Renders content on screen
• Measurable: Has width and height

ViewGroup Characteristics:

• Container: Holds other views
• Layout Manager: Defines positioning rules
• Hierarchical: Can nest other ViewGroups
• Invisible: Usually not directly visible

vi) How to Use Tab Layout in Android

Step 1: Add Dependencies

implementation 'com.google.android.material:material:1.9.0'
implementation 'androidx.viewpager2:viewpager2:1.0.0'

Step 2: XML Layout

<com.google.android.material.tabs.TabLayout
    android:id="@+id/tabLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabMode="fixed"
    app:tabGravity="fill" />

<androidx.viewpager2.widget.ViewPager2
    android:id="@+id/viewPager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

Step 3: Fragment Adapter

public class TabPagerAdapter extends FragmentStateAdapter {
    public TabPagerAdapter(FragmentActivity fa) {
        super(fa);
    }

    @Override
    public Fragment createFragment(int position) {
        switch (position) {
            case 0: return new Tab1Fragment();
            case 1: return new Tab2Fragment();
            case 2: return new Tab3Fragment();
            default: return new Tab1Fragment();
        }
    }

    @Override
    public int getItemCount() {
        return 3;
    }
}

Step 4: Activity Setup

TabLayout tabLayout = findViewById(R.id.tabLayout);
ViewPager2 viewPager = findViewById(R.id.viewPager);

TabPagerAdapter adapter = new TabPagerAdapter(this);
viewPager.setAdapter(adapter);

new TabLayoutMediator(tabLayout, viewPager,
    (tab, position) -> {
        switch (position) {
            case 0: tab.setText("Tab 1"); break;
            case 1: tab.setText("Tab 2"); break;
            case 2: tab.setText("Tab 3"); break;
        }
    }).attach();

vii) Difference between Emulator and Simulators

Aspect	Emulator	Simulator
Definition	Imitates hardware and software	Mimics software behavior only
Hardware	Emulates actual device hardware	Simulates software environment
Performance	Slower, more resource intensive	Faster, less resource intensive
Accuracy	More accurate device behavior	Less accurate, approximate behavior
Testing	Comprehensive testing possible	Limited testing capabilities
Development	Android development (AVD)	iOS development (iOS Simulator)
Binary Code	Runs actual device binaries	Runs translated/adapted code
Platform	Cross-platform possible	Usually platform-specific

Emulator Characteristics:

• Complete Emulation: Emulates entire device system
• Real OS: Runs actual Android OS
• Hardware Simulation: Simulates CPU, memory, sensors
• Debug Support: Full debugging capabilities
• Performance Impact: Higher system resource usage

Simulator Characteristics:

• Software Only: Simulates software environment
• Host OS: Runs on host operating system
• Faster Execution: Less computational overhead
• Limited Hardware: No hardware-level simulation
• Platform Dependent: Usually tied to specific platforms

Use Cases:

• Emulator: Android development, testing device-specific features
• Simulator: iOS development, quick UI testing, performance testing