SharedPreferences / DataStore in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get an instance of SharedPreferences in an Activity.

Android Kotlin

val sharedPrefs = getSharedPreferences([1], Context.MODE_PRIVATE)

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

A"my_prefs"

Bthis

C"prefs"

DMODE_PRIVATE

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable instead of a string literal for the name.

Passing the mode as the first argument.

You need to provide the name of the SharedPreferences file as a string. "my_prefs" is a common example.

2fill in blank

medium

Complete the code to save a string value "user_name" in SharedPreferences.

Android Kotlin

sharedPrefs.edit().putString([1], "John").apply()

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

A"name"

B"user_name"

CuserName

D"username"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable instead of a string literal for the key.

Misspelling the key string.

The key used to store the string should be "user_name" as specified.

3fill in blank

hard

Fix the error in the code to read an integer value "age" from SharedPreferences with default 0.

Android Kotlin

val age = sharedPrefs.getInt([1], 0)

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

Aage

BdefaultAge

C0

D"age"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable instead of a string literal for the key.

Passing the default value as the key.

The key must be a string literal "age" to correctly retrieve the value.

4fill in blank

hard

Fill both blanks to create a DataStore instance named "user_prefs" in a Context.

Android Kotlin

val dataStore: DataStore<Preferences> = context.[1](name = [2])

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

AcreateDataStore

B"user_prefs"

C"prefs"

DdataStore

Attempts:

3 left

💡 Hint

Common Mistakes

Using an incorrect function name.

Passing the name without quotes.

Use createDataStore function with the name "user_prefs" to create the DataStore instance.

5fill in blank

hard

Fill all three blanks to read a string preference "email" from DataStore with default "".

Android Kotlin

val emailFlow: Flow<String> = dataStore.data.map { preferences ->
  preferences[[1]] ?: [2]
}

val EMAIL_KEY = stringPreferencesKey([3])

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

AEMAIL_KEY

B""

C"email"

Demail

Attempts:

3 left

💡 Hint

Common Mistakes

Using the string "email" directly instead of the key variable.

Using null instead of empty string as default.

EMAIL_KEY is the key used to access the preference. The default value is an empty string "". The key name is "email".