1 /*
2  * Copyright 2024 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package androidx.lifecycle.viewmodel.compose
18 
19 import androidx.compose.runtime.Composable
20 import androidx.compose.runtime.CompositionLocalProvider
21 import androidx.compose.runtime.ProvidedValue
22 import androidx.compose.runtime.compositionLocalOf
23 import androidx.lifecycle.ViewModelStoreOwner
24 
25 /** The CompositionLocal containing the current [ViewModelStoreOwner]. */
26 public object LocalViewModelStoreOwner {
<lambda>null27     private val LocalViewModelStoreOwner = compositionLocalOf<ViewModelStoreOwner?> { null }
28 
29     /**
30      * Returns current composition local value for the owner or `null` if one has not been provided
31      * nor is one available via [findViewTreeViewModelStoreOwner] on the current
32      * [androidx.compose.ui.platform.LocalView].
33      */
34     public val current: ViewModelStoreOwner?
35         @Composable get() = LocalViewModelStoreOwner.current ?: findViewTreeViewModelStoreOwner()
36 
37     /**
38      * Associates a [LocalViewModelStoreOwner] key to a value in a call to
39      * [CompositionLocalProvider].
40      */
providesnull41     public infix fun provides(
42         viewModelStoreOwner: ViewModelStoreOwner
43     ): ProvidedValue<ViewModelStoreOwner?> {
44         return LocalViewModelStoreOwner.provides(viewModelStoreOwner)
45     }
46 }
47 
findViewTreeViewModelStoreOwnernull48 @Composable internal expect fun findViewTreeViewModelStoreOwner(): ViewModelStoreOwner?
49