Why local data enables offline functionality in iOS Swift - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to save data locally using UserDefaults.

iOS Swift

UserDefaults.standard.set([1], forKey: "username")

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Aset

Busername

CUserDefaults

D"JohnDoe"

Attempts:

3 left

💡 Hint

Common Mistakes

Using the key name instead of the value

Using the UserDefaults object instead of a value

We save the string "JohnDoe" locally with the key "username" to access it offline.

2fill in blank

medium

Complete the code to retrieve a locally saved string from UserDefaults.

iOS Swift

let name = UserDefaults.standard.string(forKey: [1])

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A"username"

Bname

CUserDefaults

D"user"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name instead of the key string

Using a wrong key string

We use the same key "username" to get the saved string from local storage.

3fill in blank

hard

Fix the error in the code to save an integer locally.

iOS Swift

UserDefaults.standard.[1](25, forKey: "age")

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Aset

BsetInteger

Csave

Dstore

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'setInteger' instead of 'set'

Using save or store which don't exist

The correct method to save any type is 'set'.

4fill in blank

hard

Fill both blanks to check if local data exists and print it.

iOS Swift

if let name = UserDefaults.standard.[1](forKey: [2]) {
  print(name)
}

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Astring

B"username"

C"user"

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong key strings

Using wrong method names

We use 'string' to get the string value and the key must be "username" to match saved data.

5fill in blank

hard

Fill all three blanks to save, retrieve, and print a boolean value locally.

iOS Swift

UserDefaults.standard.[1](true, forKey: [2])
let isLoggedIn = UserDefaults.standard.[3](forKey: "loggedIn")
print(isLoggedIn)

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Aset

B"loggedIn"

Cbool

Dstring

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'string' to retrieve boolean

Using wrong keys

We save with 'set', use the key "loggedIn", and retrieve with 'bool' method for boolean values.