rememberSaveable for configuration changes in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to save the state of the counter across configuration changes using rememberSaveable.

Android Kotlin

var counter by [1] { mutableStateOf(0) }

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

AstateOf()

BrememberSaveable()

CmutableStateOf()

Dremember()

Attempts:

3 left

💡 Hint

Common Mistakes

Using remember() instead of rememberSaveable() causes state loss on rotation.

Using mutableStateOf() alone does not save state across configuration changes.

Using rememberSaveable() ensures the counter value is saved and restored across configuration changes like screen rotations.

2fill in blank

medium

Complete the code to create a button that increments the counter saved with rememberSaveable.

Android Kotlin

Button(onClick = { counter [1] 1 }) {
    Text("Increment")
}

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

A+=

B*=

C-=

D/=

Attempts:

3 left

💡 Hint

Common Mistakes

Using -= decreases the counter instead of increasing it.

Using *= or /= changes the value incorrectly.

The += operator increases the counter by 1 each time the button is clicked.

3fill in blank

hard

Fix the error in the code to properly save a String state across configuration changes.

Android Kotlin

var name by [1] { mutableStateOf("") }

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

AmutableStateOf()

Bremember()

CrememberSaveable()

Dstate()

Attempts:

3 left

💡 Hint

Common Mistakes

Using remember() causes the state to reset on rotation.

Using mutableStateOf() alone does not save state across configuration changes.

rememberSaveable() is needed to save the String state across configuration changes, unlike remember().

4fill in blank

hard

Fill both blanks to create a rememberSaveable state for a Boolean flag and toggle it on button click.

Android Kotlin

var isChecked by [1] { mutableStateOf(false) }
Button(onClick = { isChecked = ![2] }) {
    Text("Toggle")
}

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

ArememberSaveable()

BisChecked

Cremember()

Dflag

Attempts:

3 left

💡 Hint

Common Mistakes

Using remember() instead of rememberSaveable() loses state on rotation.

Negating the wrong variable name causes errors.

The Boolean state isChecked is saved with rememberSaveable() and toggled by negating its current value.

5fill in blank

hard

Fill all three blanks to create a rememberSaveable state for a String, update it on text input, and display it.

Android Kotlin

var text by [1] { mutableStateOf("") }
TextField(value = [2], onValueChange = { [3] = it })
Text(text = text)

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

ArememberSaveable()

Btext

Dremember()

Attempts:

3 left

💡 Hint

Common Mistakes

Using remember() loses state on configuration changes.

Not updating the correct variable on input change.

The String state text is saved with rememberSaveable(), updated on input change, and displayed below.