SavedStateReader

Artifact: androidx.savedstate:savedstate

Kotlin |Java

Cmn
```
value class SavedStateReader
```

An inline class that encapsulates an opaque SavedState, and provides an API for reading the platform specific state.

See also
`read`

Summary

Public functions
`inline operator Boolean`	`contains(key: String)` Checks if the `SavedState` contains the specified `key`.	Cmn android
`inline Boolean`	`getBoolean(key: String)` Retrieves a `Boolean` value associated with the specified `key`.	Cmn android
`inline Boolean`	`getBooleanOrElse(key: String, defaultValue: () -> Boolean)` Retrieves a `Boolean` value associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline Double`	`getDouble(key: String)` Retrieves a `Double` value associated with the specified `key`.	Cmn android
`inline Double`	`getDoubleOrElse(key: String, defaultValue: () -> Double)` Retrieves a `Double` value associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline Float`	`getFloat(key: String)` Retrieves a `Float` value associated with the specified `key`.	Cmn android
`inline Float`	`getFloatOrElse(key: String, defaultValue: () -> Float)` Retrieves a `Float` value associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline Int`	`getInt(key: String)` Retrieves an `Int` value associated with the specified `key`.	Cmn android
`inline List<Int>`	`getIntList(key: String)` Retrieves a `List` of elements of `Int` associated with the specified `key`.	Cmn android
`inline List<Int>`	`getIntListOrElse(key: String, defaultValue: () -> List<Int>)` Retrieves a `List` of elements of `Int` associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline Int`	`getIntOrElse(key: String, defaultValue: () -> Int)` Retrieves an `Int` value associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline T`	`<T : Parcelable> getParcelable(key: String)` Retrieves a `Parcelable` object associated with the specified key.	android
`inline List<T>`	`<T : Parcelable> getParcelableList(key: String)` Retrieves a `List` of elements of `Parcelable` associated with the specified `key`.	android
`inline List<T>`	`<T : Parcelable> getParcelableListOrElse( key: String, defaultValue: () -> List<T> )` Retrieves a `List` of elements of `Parcelable` associated with the specified `key`, or a default value if the `key` doesn't exist.	android
`inline T`	`<T : Parcelable> getParcelableOrElse(key: String, defaultValue: () -> T)` Retrieves a `Parcelable` object associated with the specified key, or a default value if the key doesn't exist.	android
`inline SavedState`	`getSavedState(key: String)` Retrieves a `SavedState` object associated with the specified `key`.	Cmn android
`inline SavedState`	`getSavedStateOrElse(key: String, defaultValue: () -> SavedState)` Retrieves a `SavedState` object associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline String`	`getString(key: String)` Retrieves a `String` value associated with the specified `key`.	Cmn android
`inline List<String>`	`getStringList(key: String)` Retrieves a `List` of elements of `String` associated with the specified `key`.	Cmn android
`inline List<String>`	`getStringListOrElse(key: String, defaultValue: () -> List<String>)` Retrieves a `List` of elements of `String` associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline String`	`getStringOrElse(key: String, defaultValue: () -> String)` Retrieves a `String` value associated with the specified `key`, or a default value if the `key` doesn't exist.	Cmn android
`inline Boolean`	`isEmpty()` Checks if the `SavedState` is empty (contains no key-value pairs).	Cmn android
`inline Int`	`size()` Returns the number of key-value pairs in the `SavedState`.	Cmn android

Extension functions
`inline T`	`<T : Any?> SavedStateReader.write(block: SavedStateWriter.() -> T)` Calls the specified function `block` with a `SavedStateWriter` value as its receiver and returns the `block` value.	Cmn

Public functions

contains

Cmn android

Added in 1.3.0-alpha02

inline operator fun contains(key: String): Boolean

Checks if the SavedState contains the specified key.

Parameters
`key: String`	The `key` to check for.

Returns
`Boolean`	`true` if the `SavedState` contains the `key`, `false` otherwise.

getBoolean

Cmn android

Added in 1.3.0-alpha02

inline fun getBoolean(key: String): Boolean

Retrieves a Boolean value associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`Boolean`	The `Boolean` value associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getBooleanOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getBooleanOrElse(key: String, defaultValue: () -> Boolean): Boolean

Retrieves a Boolean value associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> Boolean`	A function providing the default value if the `key` is not found.

Returns
`Boolean`	The `Boolean` value associated with the `key`, or the default value if the `key` is not found.

getDouble

Cmn android

Added in 1.3.0-alpha02

inline fun getDouble(key: String): Double

Retrieves a Double value associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`Double`	The `Double` value associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getDoubleOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getDoubleOrElse(key: String, defaultValue: () -> Double): Double

Retrieves a Double value associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> Double`	A function providing the default value if the `key` is not found.

Returns
`Double`	The `Double` value associated with the `key`, or the default value if the `key` is not found.

getFloat

Cmn android

Added in 1.3.0-alpha02

inline fun getFloat(key: String): Float

Retrieves a Float value associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`Float`	The `Float` value associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getFloatOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getFloatOrElse(key: String, defaultValue: () -> Float): Float

Retrieves a Float value associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> Float`	A function providing the default value if the `key` is not found.

Returns
`Float`	The `Float` value associated with the `key`, or the default value if the `key` is not found.

getInt

Cmn android

Added in 1.3.0-alpha02

inline fun getInt(key: String): Int

Retrieves an Int value associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`Int`	The `Int` value associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getIntList

Cmn android

Added in 1.3.0-alpha02

inline fun getIntList(key: String): List<Int>

Retrieves a List of elements of Int associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`List<Int>`	The `List` of elements of `Int` associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getIntListOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getIntListOrElse(key: String, defaultValue: () -> List<Int>): List<Int>

Retrieves a List of elements of Int associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> List<Int>`	A function providing the default value if the `key` is not found or the retrieved value is not a list of `Int`.

Returns
`List<Int>`	The list of elements of `Int` associated with the `key`, or the default value if the `key` is not found.

getIntOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getIntOrElse(key: String, defaultValue: () -> Int): Int

Retrieves an Int value associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> Int`	A function providing the default value if the `key` is not found.

Returns
`Int`	The `Int` value associated with the `key`, or the default value if the `key` is not found.

getParcelable

android

inline fun <T : Parcelable> getParcelable(key: String): T

Retrieves a Parcelable object associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The key to retrieve the value for.

Returns
`T`	The `Parcelable` object associated with the key.

Throws
`kotlin.IllegalStateException`	If the key is not found.

getParcelableList

android

inline fun <T : Parcelable> getParcelableList(key: String): List<T>

Retrieves a List of elements of Parcelable associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`List<T>`	The `List` of elements of `Parcelable` associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getParcelableListOrElse

android

inline fun <T : Parcelable> getParcelableListOrElse(
    key: String,
    defaultValue: () -> List<T>
): List<T>

Retrieves a List of elements of Parcelable associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> List<T>`	A function providing the default value if the `key` is not found or the retrieved value is not a list of `Parcelable`.

Returns
`List<T>`	The list of elements of `Parcelable` associated with the `key`, or the default value if the `key` is not found.

getParcelableOrElse

android

inline fun <T : Parcelable> getParcelableOrElse(key: String, defaultValue: () -> T): T

Retrieves a Parcelable object associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The key to retrieve the value for.
`defaultValue: () -> T`	A function providing the default `Parcelable` if the key is not found.

Returns
`T`	The `Parcelable` object associated with the key, or the default value if the key is not found.

getSavedState

Cmn android

Added in 1.3.0-alpha02

inline fun getSavedState(key: String): SavedState

Retrieves a SavedState object associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`SavedState`	The `SavedState` object associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getSavedStateOrElse

Cmn android

inline fun getSavedStateOrElse(key: String, defaultValue: () -> SavedState): SavedState

Retrieves a SavedState object associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> SavedState`	A function providing the default `SavedState` if the `key` is not found.

Returns
`SavedState`	The `SavedState` object associated with the `key`, or the default value if the `key` is not found.

getString

Cmn android

Added in 1.3.0-alpha02

inline fun getString(key: String): String

Retrieves a String value associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`String`	The `String` value associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getStringList

Cmn android

Added in 1.3.0-alpha02

inline fun getStringList(key: String): List<String>

Retrieves a List of elements of String associated with the specified key. Throws an IllegalStateException if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.

Returns
`List<String>`	The `List` of elements of `String` associated with the `key`.

Throws
`kotlin.IllegalStateException`	If the `key` is not found.

getStringListOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getStringListOrElse(key: String, defaultValue: () -> List<String>): List<String>

Retrieves a List of elements of String associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> List<String>`	A function providing the default value if the `key` is not found or the retrieved value is not a list of `String`.

Returns
`List<String>`	The list of elements of `String` associated with the `key`, or the default value if the `key` is not found.

getStringOrElse

Cmn android

Added in 1.3.0-alpha02

inline fun getStringOrElse(key: String, defaultValue: () -> String): String

Retrieves a String value associated with the specified key, or a default value if the key doesn't exist.

Parameters
`key: String`	The `key` to retrieve the value for.
`defaultValue: () -> String`	A function providing the default value if the `key` is not found.

Returns
`String`	The `String` value associated with the `key`, or the default value if the `key` is not found.

isEmpty

Cmn android

Added in 1.3.0-alpha02

inline fun isEmpty(): Boolean

Checks if the SavedState is empty (contains no key-value pairs).

Returns
`Boolean`	`true` if the `SavedState` is empty, `false` otherwise.

size

Cmn android

Added in 1.3.0-alpha02

inline fun size(): Int

Returns the number of key-value pairs in the SavedState.

Returns
`Int`	The size of the `SavedState`.

Extension functions

write

Cmn

Artifact: androidx.savedstate:savedstate

View Source

inline fun <T : Any?> SavedStateReader.write(block: SavedStateWriter.() -> T): T

Calls the specified function block with a SavedStateWriter value as its receiver and returns the block value.

Parameters
`block: SavedStateWriter.() -> T`	A lambda function that performs write operations using the `SavedStateWriter`.

Returns
`T`	The result of the lambda function's execution.

See also
`SavedStateReader`
`SavedStateWriter`