---
title: "Saver"
description: "The [Saver] describes how the object of [Original] class can be simplified and converted into
something which is [Saveable].

What types can be saved is defined by [SaveableStateRegistry], by default everything which can be
stored in the Bundle class can be saved. The implementations can check that the provided value
can be saved via [SaverScope.canBeSaved]

You can pass the implementations of this class as a parameter for [rememberSaveable]."
type: "interface"
---

<div class='type'>Interface</div>


<a id='references'></a>

<div class='sourceset sourceset-common'>Common</div>



```kotlin
public interface Saver<Original, Saveable : Any>
```


The `Saver` describes how the object of `Original` class can be simplified and converted into
something which is `Saveable`.

What types can be saved is defined by `SaveableStateRegistry`, by default everything which can be
stored in the Bundle class can be saved. The implementations can check that the provided value
can be saved via `SaverScope.canBeSaved`

You can pass the implementations of this class as a parameter for `rememberSaveable`.


## Functions

```kotlin
public fun SaverScope.save(value: Original): Saveable?
```


Convert the value into a saveable one. If null is returned the value will not be saved.


```kotlin
public fun restore(value: Saveable): Original?
```


Convert the restored value back to the original Class. If null is returned the value will not
be restored and would be initialized again instead.



## Code Examples

### CustomSaverSample
```kotlin
@Composable
fun CustomSaverSample() {
    data class Holder(var value: Int)
    // this Saver implementation converts Holder object which we don't know how to save
    // to Int which we can save
    val HolderSaver = Saver<Holder, Int>(save = { it.value }, restore = { Holder(it) })
}
```