Project structure (app, gradle, manifests) in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the Android app module directory name in the project.

Android Kotlin

rootProject.name = "MyApplication"
include(":[1]")

Drag options to blanks, or click blank then click option'

Aapp

Bbuild

Cgradle

Dmanifest

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'build' or 'gradle' which are build system folders, not modules.

Confusing 'manifest' with module name.

The main Android app module is usually named app. This is where your app code and resources live.

2fill in blank

medium

Complete the Gradle build script line to apply the Android application plugin.

Android Kotlin

plugins {
    id("[1]")
}

Drag options to blanks, or click blank then click option'

Aapplication

Bjava-library

Ccom.android.application

Dkotlin

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'application' which is for plain Java/Kotlin apps, not Android.

Using 'java-library' which is for Java libraries.

The plugin com.android.application is used to build Android apps.

3fill in blank

hard

Fix the error in the AndroidManifest.xml root tag to declare the correct XML namespace.

Android Kotlin

<manifest xmlns:android="[1]"
    package="com.example.app">
</manifest>

Drag options to blanks, or click blank then click option'

Ahttp://www.w3.org/2000/xmlns/

Bhttp://schemas.android.com/apk/res/android

Chttp://schemas.android.com/tools

Dhttp://schemas.android.com/apk/res-auto

Attempts:

3 left

💡 Hint

Common Mistakes

Using the tools namespace URL instead of the Android namespace.

Using XML namespace URLs unrelated to Android.

The AndroidManifest.xml must declare the xmlns:android namespace as http://schemas.android.com/apk/res/android.

4fill in blank

hard

Fill both blanks to declare the minimum SDK version and target SDK version in build.gradle.kts.

Android Kotlin

android {
    defaultConfig {
        minSdk = [1]
        targetSdk = [2]
    }
}

Drag options to blanks, or click blank then click option'

A21

B30

CcompileSdkVersion

DandroidVersion

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing compileSdkVersion with minSdkVersion or targetSdkVersion.

Using invalid values or variable names.

The minSdk sets the minimum Android version supported, and targetSdk sets the version the app targets.

5fill in blank

hard

Fill all three blanks to define the application ID, version code, and version name in build.gradle.kts.

Android Kotlin

android {
    defaultConfig {
        applicationId = "[1]"
        versionCode = [2]
        versionName = "[3]"
    }
}

Drag options to blanks, or click blank then click option'

Acom.example.myapp

B1

C1.0

Dcom.example.app

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid application IDs or missing quotes.

Using non-integer version codes.

Confusing versionCode and versionName formats.

The applicationId uniquely identifies your app. versionCode is an integer for updates, and versionName is a user-friendly version string.

Practice

1. What is the main purpose of the app folder in an Android project?

easy

A. It stores the build configuration files.

B. It contains the app's source code and resources.

C. It holds the Android system files.

D. It contains the device emulator settings.

Solution

1. Step 1: Understand the app folder role

   The app folder is where you put your app's code and resources like images and layouts.

2. Step 2: Differentiate from other folders

   Build files like build.gradle are outside or inside app but serve different purposes; system files are not in app.

3. Final Answer:

   It contains the app's source code and resources. -> Option B

4. Quick Check:

   App folder = source code and resources [OK]

Hint: App folder = your app's code and resources [OK]

Common Mistakes:

• Confusing build files with app folder contents
• Thinking system files are inside app folder
• Mixing emulator settings with project structure

2. Which file in an Android project declares the app's components and permissions?

easy

A. build.gradle

B. proguard-rules.pro

C. settings.gradle

D. AndroidManifest.xml

Solution

1. Step 1: Identify the manifest file role

   The AndroidManifest.xml file describes app components like activities and permissions.

2. Step 2: Compare with other files

   build.gradle handles build settings, settings.gradle manages modules, and proguard-rules.pro is for code shrinking rules.

3. Final Answer:

   AndroidManifest.xml -> Option D

4. Quick Check:

   Manifest = app components and permissions [OK]

Hint: Manifest file = app components and permissions [OK]

Common Mistakes:

• Confusing build.gradle with manifest
• Thinking settings.gradle declares permissions
• Mixing ProGuard rules with app declarations

3. Given this snippet from build.gradle inside the app folder, what will happen if you add a new dependency incorrectly?

dependencies {
    implementation 'androidx.core:core-ktx:1.9.0'
    implementation 'com.google.android.material:material:1.7.0'
}

medium

A. The app will build successfully with all dependencies.

B. The app will run but crash at runtime due to missing classes.

C. The build will fail due to a syntax error in dependencies.

D. The build will ignore the incorrect dependency and continue.

Solution

1. Step 1: Understand dependency syntax

   Dependencies must be declared with correct syntax like implementation 'group:name:version'. Any syntax error causes build failure.

2. Step 2: Consequence of incorrect dependency

   If a dependency line is malformed, Gradle will fail to build and show an error, not ignore it or allow runtime crashes.

3. Final Answer:

   The build will fail due to a syntax error in dependencies. -> Option C

4. Quick Check:

   Incorrect dependency syntax = build failure [OK]

Hint: Syntax errors in build.gradle cause build failure [OK]

Common Mistakes:

• Assuming build ignores syntax errors
• Thinking runtime crashes happen from build errors
• Confusing dependency syntax with code syntax

4. You added a new permission in AndroidManifest.xml but the app crashes on launch. What is a likely cause?

medium

A. The permission tag is outside the manifest root element.

B. The build.gradle file is missing the permission.

C. The app folder is empty.

D. The emulator does not support permissions.

Solution

1. Step 1: Check manifest XML structure

   All permission tags must be inside the root <manifest> element. Placing them outside causes XML errors and app crashes.

2. Step 2: Understand build.gradle and emulator roles

   Permissions are declared only in manifest, not build.gradle. Emulators support permissions normally.

3. Final Answer:

   The permission tag is outside the <manifest> root element. -> Option A

4. Quick Check:

   Permissions must be inside manifest root [OK]

Hint: Permission tags must be inside <manifest> root [OK]

Common Mistakes:

• Adding permissions in build.gradle
• Ignoring XML structure errors
• Blaming emulator for permission issues

5. You want to add a new module to your Android project. Which files/folders must you update or create to integrate it properly?

hard

A. Create a new folder for the module, add a build.gradle for it, and update settings.gradle to include it.

B. Add the module folder inside app and update AndroidManifest.xml only.

C. Create a new folder and add dependencies in app/build.gradle only.

D. Add the module folder anywhere and no other changes are needed.

Solution

1. Step 1: Create module folder and build file

   Each module needs its own folder and build.gradle to define its build settings.

2. Step 2: Update settings.gradle

   The settings.gradle file must include the new module so Gradle knows to build it.

3. Final Answer:

   Create a new folder for the module, add a build.gradle for it, and update settings.gradle to include it. -> Option A

4. Quick Check:

   New module = folder + build.gradle + settings.gradle update [OK]

Hint: New module needs folder, build.gradle, and settings.gradle update [OK]

Common Mistakes:

• Only updating AndroidManifest.xml
• Adding module inside app folder incorrectly
• Forgetting to update settings.gradle