| /* |
| * Copyright 2019 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 |
| * |
| * http://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. |
| */ |
| |
| @file:Suppress("unused", "UNUSED_PARAMETER", "UNUSED_VARIABLE") |
| |
| package androidx.compose.runtime.samples |
| |
| import androidx.annotation.Sampled |
| import androidx.compose.runtime.Composable |
| import androidx.compose.runtime.key |
| |
| @Sampled |
| @Composable |
| fun locallyUniqueKeys() { |
| for (user in users) { |
| key(user.id) { UserPreview(user = user) } |
| } |
| |
| for (user in users.filter { isAdmin }) { |
| key(user.id) { Friend(friend = user) } |
| } |
| } |
| |
| @Sampled |
| @Composable |
| fun notAlwaysUniqueKeys() { |
| for ((child, parent) in relationships) { |
| key(parent.id) { |
| User(user = child) |
| User(user = parent) |
| } |
| } |
| } |
| |
| @Sampled |
| @Composable |
| fun moreCorrectUniqueKeys() { |
| for ((child, parent) in relationships) { |
| key(parent.id to child.id) { |
| User(user = child) |
| User(user = parent) |
| } |
| } |
| } |
| |
| @Composable private fun User(user: User) {} |
| |
| @Composable private fun UserPreview(user: User) {} |
| |
| @Composable private fun Friend(friend: User) {} |
| |
| private const val isAdmin = true |
| |
| private val users = listOf<User>() |
| private val relationships = mapOf<User, User>() |
| private val child = User() |