Alex Vanyo
3 years ago
committed by
Don Turner
parent
707c9d04e7
commit
f9d8d45ecb
@ -1,91 +0,0 @@
|
||||
/*
|
||||
* Copyright 2022 The Android Open Source Project
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* https://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package com.google.samples.apps.nowinandroid.feature.foryou.util
|
||||
|
||||
import androidx.compose.runtime.MutableState
|
||||
import androidx.compose.runtime.getValue
|
||||
import androidx.compose.runtime.saveable.Saver
|
||||
import androidx.compose.runtime.saveable.autoSaver
|
||||
import androidx.compose.runtime.setValue
|
||||
import androidx.lifecycle.SavedStateHandle
|
||||
import androidx.lifecycle.viewmodel.compose.SavedStateHandleSaveableApi
|
||||
import androidx.lifecycle.viewmodel.compose.saveable
|
||||
import kotlin.properties.PropertyDelegateProvider
|
||||
import kotlin.properties.ReadOnlyProperty
|
||||
import kotlin.properties.ReadWriteProperty
|
||||
import kotlin.reflect.KProperty
|
||||
|
||||
// These are placeholder solutions for https://issuetracker.google.com/issues/224565154 and
|
||||
// https://issuetracker.google.com/issues/225014345.
|
||||
// With the following, it is possible to use the Compose Saver APIs to back values in the
|
||||
// SavedStateHandle to persist through process death, in a similar form as rememberSaveable
|
||||
|
||||
/**
|
||||
* A [PropertyDelegateProvider] allowing the use of [saveable] with the key provided by the name
|
||||
* of the property.
|
||||
*
|
||||
* https://issuetracker.google.com/issues/225014345
|
||||
*/
|
||||
@OptIn(SavedStateHandleSaveableApi::class)
|
||||
fun <T : Any> SavedStateHandle.saveable(
|
||||
saver: Saver<T, out Any> = autoSaver(),
|
||||
init: () -> T,
|
||||
): PropertyDelegateProvider<Any, ReadOnlyProperty<Any, T>> =
|
||||
PropertyDelegateProvider { _, property ->
|
||||
val value = saveable(
|
||||
key = property.name,
|
||||
saver = saver,
|
||||
init = init
|
||||
)
|
||||
|
||||
ReadOnlyProperty { _, _ -> value }
|
||||
}
|
||||
|
||||
/**
|
||||
* A nested [PropertyDelegateProvider] allowing the use of [saveable] with the key provided by the
|
||||
* name, as well as direct access to the value contained with [MutableState].
|
||||
*
|
||||
* This allows the main usage to look almost identical to
|
||||
* `rememberSaveable { mutableStateOf(...) }`:
|
||||
*
|
||||
* ```
|
||||
* val value by savedStateHandle.saveable { mutableStateOf("initialValue") }
|
||||
* ```
|
||||
*
|
||||
* https://issuetracker.google.com/issues/225014345
|
||||
*/
|
||||
@OptIn(SavedStateHandleSaveableApi::class)
|
||||
@JvmName("saveableMutableState")
|
||||
fun <T : Any> SavedStateHandle.saveable(
|
||||
stateSaver: Saver<T, out Any> = autoSaver(),
|
||||
init: () -> MutableState<T>,
|
||||
): PropertyDelegateProvider<Any, ReadWriteProperty<Any, T>> =
|
||||
PropertyDelegateProvider<Any, ReadWriteProperty<Any, T>> { _, property ->
|
||||
val mutableState = saveable(
|
||||
key = property.name,
|
||||
stateSaver = stateSaver,
|
||||
init = init
|
||||
)
|
||||
|
||||
object : ReadWriteProperty<Any, T> {
|
||||
override fun getValue(thisRef: Any, property: KProperty<*>): T =
|
||||
mutableState.getValue(thisRef, property)
|
||||
|
||||
override fun setValue(thisRef: Any, property: KProperty<*>, value: T) =
|
||||
mutableState.setValue(thisRef, property, value)
|
||||
}
|
||||
}
|
||||
Loading…
Reference in new issue