Firebase Analytics in Android Kotlin - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ ui_behavior

intermediate

Logging a Custom Event with Parameters

You want to log a custom event named "purchase_complete" with parameters item_id and price using Firebase Analytics in Kotlin. Which code snippet correctly logs this event?

Android Kotlin

val analytics = Firebase.analytics
// Log event here

A

analytics.logEvent("purchase_complete") {
  param("item_id", "sku123")
  param("price", 9.99)
}

B analytics.logEvent("purchase_complete", mapOf("item_id" to "sku123", "price" to 9.99))

C

val bundle = Bundle().apply {
  putString("item_id", "sku123")
  putDouble("price", 9.99)
}
analytics.logEvent("purchase_complete", bundle)

D analytics.logEvent("purchase_complete", Bundle().putString("item_id", "sku123"))

💡 Hint

Remember that Firebase Analytics expects a Bundle object for event parameters in Kotlin.

Firebase Analytics in Kotlin requires event parameters to be passed as a Bundle object. Option C correctly creates a Bundle with the parameters and logs the event. Option C uses a Kotlin DSL style which is not supported. Option C tries to pass a Map which is invalid. Option C passes a Bundle but only with one parameter and incorrectly chains putString without storing the Bundle.

❓ lifecycle

intermediate

When to Initialize Firebase Analytics

In an Android app using Kotlin, where is the best place to initialize Firebase Analytics to ensure it is ready for logging events throughout the app?

A In the <code>Application</code> class <code>onCreate()</code> method

B Inside the <code>onCreate()</code> method of the main <code>Activity</code>

C Inside the <code>onStart()</code> method of every <code>Activity</code>

D Right before logging each event

💡 Hint

Think about initializing once for the whole app lifecycle.

Initializing Firebase Analytics in the Application class's onCreate() method ensures it is set up once when the app starts and is available throughout the app lifecycle. Initializing in each Activity or before each event is inefficient and error-prone.

📝 Syntax

advanced

Correct Syntax for Setting User Property

Which Kotlin code snippet correctly sets a user property named "favorite_genre" with value "sci-fi" using Firebase Analytics?

Android Kotlin

val analytics = Firebase.analytics
// Set user property here

A analytics.setUserProperty("favorite_genre", value = "sci-fi")

B analytics.setUserProperty("favorite_genre", "sci-fi")

C analytics.setUserProperty("favorite_genre" to "sci-fi")

D analytics.setUserProperty(name = "favorite_genre", "sci-fi")

💡 Hint

Check the method signature for setUserProperty in Firebase Analytics Kotlin API.

The correct method call is setUserProperty(name: String, value: String?). Option B matches this signature. Option B uses a Pair which is invalid. Option B uses a named argument 'value' which is allowed but the method signature does not define a named parameter 'value' explicitly, so it may cause an error. Option B mixes named and positional arguments incorrectly.

❓ navigation

advanced

Tracking Screen Views Correctly

You want to track screen views in your Android app using Firebase Analytics. Which approach correctly logs the screen name "HomeScreen" when the user navigates to it?

A analytics.setCurrentScreen(this, "HomeScreen", "MainActivity")

B

analytics.logEvent(FirebaseAnalytics.Event.SCREEN_VIEW) {
  param(FirebaseAnalytics.Param.SCREEN_NAME, "HomeScreen")
}

C

analytics.logEvent("screen_view", Bundle().apply {
  putString("screen_name", "HomeScreen")
})

D analytics.setCurrentScreen(this, "HomeScreen", null)

💡 Hint

Check the official Firebase method for setting current screen with activity context.

Option A correctly calls setCurrentScreen with the activity context, screen name, and screen class override. Option A is deprecated and may cause runtime errors. Option A uses a Kotlin DSL style which is not supported. Option A logs a custom event but does not set the current screen properly.

🔧 Debug

expert

Diagnosing Missing Analytics Events

You notice that some custom events are not appearing in Firebase Analytics dashboard after logging them in your Kotlin app. Which of the following is the MOST likely cause?

A You did not call <code>FirebaseApp.initializeApp(context)</code> explicitly in your Application class

B You logged events before initializing Firebase Analytics instance

C You forgot to add the Firebase Analytics dependency in your build.gradle file

D You used event names longer than 40 characters or with invalid characters

💡 Hint

Firebase Analytics enforces naming rules for events.

Firebase Analytics requires event names to be 40 characters or less and only contain alphanumeric characters and underscores. Using invalid event names causes events to be dropped silently. Option D would cause compile errors. Option D usually causes runtime errors. Option D is not required if Firebase is configured properly via google-services plugin.