androidx.savedstate.serialization

Kotlin |Java

Classes

`SavedStateConfiguration`	Configuration of the current `SavedStateConfiguration` configured with `SavedStateConfiguration.Builder`.	Cmn
`SavedStateConfiguration.Builder`	Builder of the `SavedStateConfiguration` instance provided by `SavedStateConfig { ... }` factory function.	Cmn

Objects

ClassDiscriminatorMode

Defines which classes and objects should have their serial name included in the json as so-called class discriminator.

Cmn

Top-level functions summary

`SavedStateConfiguration`	`SavedStateConfiguration( from: SavedStateConfiguration, builderAction: SavedStateConfiguration.Builder.() -> Unit )` Creates an instance of `SavedStateConfiguration` configured from the optionally given `from` and adjusted with `builderAction`.	Cmn
`inline T`	`<T : Any> decodeFromSavedState( savedState: SavedState, configuration: SavedStateConfiguration )` Decode a serializable object from a `SavedState` with the default deserializer.	Cmn
`T`	`<T : Any> decodeFromSavedState( deserializer: <Error class: unknown class><T>, savedState: SavedState, configuration: SavedStateConfiguration )` Decodes and deserializes the given `SavedState` to the value of type `T` using the given `deserializer`.	Cmn
`inline SavedState`	`<T : Any> encodeToSavedState( value: T, configuration: SavedStateConfiguration )` Serializes the `value` of type `T` into an equivalent `SavedState` using KSerializer retrieved from the reified type parameter.	Cmn
`SavedState`	`<T : Any> encodeToSavedState( serializer: <Error class: unknown class><T>, value: T, configuration: SavedStateConfiguration )` Serializes and encodes the given `value` to `SavedState` using the given `serializer`.	Cmn

Extension functions summary

`inline ReadWriteProperty<Any?, T>`	`<T : Any?> SavedStateRegistryOwner.saved( key: String?, configuration: SavedStateConfiguration, noinline init: () -> T )` Returns a property delegate that manages the saving and restoring of a value of type `T` within the `SavedStateRegistry` of this `SavedStateRegistryOwner`.	Cmn
`ReadWriteProperty<Any?, T>`	`<T : Any?> SavedStateRegistryOwner.saved( serializer: <Error class: unknown class><T>, key: String?, configuration: SavedStateConfiguration, init: () -> T )` Returns a property delegate that manages the saving and restoring of a value of type `T` within the `SavedStateRegistry` of this `SavedStateRegistryOwner`.	Cmn

Top-level functions

SavedStateConfiguration

Cmn

Artifact: androidx.savedstate:savedstate

View Source

Added in 1.3.0

fun SavedStateConfiguration(
    from: SavedStateConfiguration = SavedStateConfiguration.DEFAULT,
    builderAction: SavedStateConfiguration.Builder.() -> Unit
): SavedStateConfiguration

Creates an instance of SavedStateConfiguration configured from the optionally given from and adjusted with builderAction.

import androidx.savedstate.serialization.SavedStateConfiguration
import androidx.savedstate.serialization.decodeFromSavedState
import androidx.savedstate.serialization.encodeToSavedState

val config = SavedStateConfiguration {
    serializersModule = SerializersModule {
        polymorphic(Any::class) { subclass(String::class) }
    }
}
val value = "foo"
val encoded =
    encodeToSavedState(
        serializer = PolymorphicSerializer(Any::class),
        value = value,
        configuration = config,
    )
val decoded =
    decodeFromSavedState(
        deserializer = PolymorphicSerializer(Any::class),
        savedState = encoded,
        configuration = config,
    )

Parameters
`from: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	An optional initial `SavedStateConfiguration` to start with. Defaults to `SavedStateConfiguration.DEFAULT`.
`builderAction: SavedStateConfiguration.Builder.() -> Unit`	A lambda function to configure the `Builder` for additional customization.

Returns
`SavedStateConfiguration`	A new `SavedStateConfiguration` instance configured based on the provided parameters.

decodeFromSavedState

Cmn

Artifact: androidx.savedstate:savedstate

View Source

inline fun <T : Any> decodeFromSavedState(
    savedState: SavedState,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT
): T

Decode a serializable object from a SavedState with the default deserializer.

Format not stable: The internal structure of the given SavedState is subject to change in future releases for optimization. While it is guaranteed to be compatible with encodeToSavedState, direct manipulation of its encoded format using keys is not recommended.

import androidx.savedstate.serialization.decodeFromSavedState

@Serializable data class User(val id: Int, val name: String)
val user = decodeFromSavedState<User>(userSavedState)

Parameters
`savedState: SavedState`	The `SavedState` to decode from.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.

Returns
`T`	The decoded object.

Throws
`SerializationException`	in case of any decoding-specific error.
`kotlin.IllegalArgumentException`	if the decoded input is not a valid instance of `T`.

See also
`encodeToSavedState`

decodeFromSavedState

Cmn

Artifact: androidx.savedstate:savedstate

View Source

fun <T : Any> decodeFromSavedState(
    deserializer: <Error class: unknown class><T>,
    savedState: SavedState,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT
): T

Decodes and deserializes the given SavedState to the value of type T using the given deserializer.

Format not stable: The internal structure of the given SavedState is subject to change in future releases for optimization. While it is guaranteed to be compatible with decodeFromSavedState, direct manipulation of its encoded format using keys is not recommended.

import androidx.savedstate.serialization.SavedStateConfiguration
import androidx.savedstate.serialization.decodeFromSavedState
import androidx.savedstate.serialization.encodeToSavedState

val config = SavedStateConfiguration {
    serializersModule = SerializersModule {
        polymorphic(Any::class) { subclass(String::class) }
    }
}
val value = "foo"
val encoded =
    encodeToSavedState(
        serializer = PolymorphicSerializer(Any::class),
        value = value,
        configuration = config,
    )
val decoded =
    decodeFromSavedState(
        deserializer = PolymorphicSerializer(Any::class),
        savedState = encoded,
        configuration = config,
    )

Parameters
`deserializer: <Error class: unknown class><T>`	The deserializer to use.
`savedState: SavedState`	The `SavedState` to decode from.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.

Returns
`T`	The deserialized object.

Throws
`SerializationException`	in case of any decoding-specific error.
`kotlin.IllegalArgumentException`	if the decoded input is not a valid instance of `T`.

See also
`encodeToSavedState`

encodeToSavedState

Cmn

Artifact: androidx.savedstate:savedstate

View Source

inline fun <T : Any> encodeToSavedState(
    value: T,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT
): SavedState

Serializes the value of type T into an equivalent SavedState using KSerializer retrieved from the reified type parameter.

Format not stable: The internal structure of the returned SavedState is subject to change in future releases for optimization. While it is guaranteed to be compatible with decodeFromSavedState, direct manipulation of its encoded format using keys is not recommended.

import androidx.savedstate.serialization.encodeToSavedState

@Serializable data class User(val id: Int, val name: String)
val user = User(123, "foo")
val savedState = encodeToSavedState(user)

Parameters
`value: T`	The serializable object to encode.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.

Returns
`SavedState`	The encoded `SavedState`.

Throws
`SerializationException`	in case of any encoding-specific error.

See also
`decodeFromSavedState`

encodeToSavedState

Cmn

Artifact: androidx.savedstate:savedstate

View Source

fun <T : Any> encodeToSavedState(
    serializer: <Error class: unknown class><T>,
    value: T,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT
): SavedState

Serializes and encodes the given value to SavedState using the given serializer.

import androidx.savedstate.serialization.SavedStateConfiguration
import androidx.savedstate.serialization.encodeToSavedState

val config = SavedStateConfiguration {
    serializersModule = SerializersModule {
        polymorphic(Any::class) { subclass(String::class) }
    }
}
val value = "foo"
val encoded =
    encodeToSavedState(
        serializer = PolymorphicSerializer(Any::class),
        value = value,
        configuration = config,
    )

Parameters
`serializer: <Error class: unknown class><T>`	The serializer to use.
`value: T`	The serializable object to encode.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.

Returns
`SavedState`	The encoded `SavedState`.

Throws
`SerializationException`	in case of any encoding-specific error.

See also
`decodeFromSavedState`

Extension functions

saved

Cmn

Artifact: androidx.savedstate:savedstate

View Source

inline fun <T : Any?> SavedStateRegistryOwner.saved(
    key: String? = null,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT,
    noinline init: () -> T
): ReadWriteProperty<Any?, T>

Returns a property delegate that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.

import androidx.activity.ComponentActivity

@Serializable data class User(val id: Int, val name: String)
class MyActivity : ComponentActivity() {
    val user by saved(key = "myKey") { User(id = 123, name = "John Doe") }
}

Parameters
`key: String? = null`	An optional `String` key to use for storing the value in the `SavedStateRegistry`. A default key will be generated if it's omitted or when 'null' is passed.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.
`noinline init: () -> T`	The function to provide the initial value of the property.

Returns
`ReadWriteProperty<Any?, T>`	A property delegate provider that manages the saving and restoring of the value.

saved

Cmn

Artifact: androidx.savedstate:savedstate

View Source

fun <T : Any?> SavedStateRegistryOwner.saved(
    serializer: <Error class: unknown class><T>,
    key: String? = null,
    configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT,
    init: () -> T
): ReadWriteProperty<Any?, T>

Returns a property delegate that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.

import androidx.activity.ComponentActivity

@Serializable data class User(val id: Int, val name: String)
class MyActivity : ComponentActivity() {
    val user by
        saved(key = "myKey", serializer = serializer()) { User(id = 123, name = "John Doe") }
}

Parameters
`serializer: <Error class: unknown class><T>`	The KSerializer to use for serializing and deserializing the value.
`key: String? = null`	An optional `String` key to use for storing the value in the `SavedStateRegistry`. A default key will be generated if it's omitted or when 'null' is passed.
`configuration: SavedStateConfiguration = SavedStateConfiguration.DEFAULT`	The `SavedStateConfiguration` to use. Defaults to `SavedStateConfiguration.DEFAULT`.
`init: () -> T`	The function to provide the initial value of the property.

Returns
`ReadWriteProperty<Any?, T>`	A property delegate provider that manages the saving and restoring of the value.