1 /* 2 * Copyright 2023 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 com.android.systemui.scene.shared.model 18 19 import com.android.compose.animation.scene.OverlayKey 20 import com.android.compose.animation.scene.SceneKey 21 import com.android.systemui.scene.ui.composable.SceneContainerTransitionsBuilder 22 23 /** Models the configuration of the scene container. */ 24 data class SceneContainerConfig( 25 26 /** 27 * The keys to all scenes in the container, sorted by z-order such that the last one renders on 28 * top of all previous ones. Scene keys within the same container must not repeat but it's okay 29 * to have the same scene keys in different containers. 30 * 31 * Note that this doesn't control how back navigation works; for that, we have 32 * [navigationDistances]. 33 */ 34 val sceneKeys: List<SceneKey>, 35 36 /** 37 * The key of the scene that is the initial current scene when the container is first set up, 38 * before taking any application state in to account. 39 */ 40 val initialSceneKey: SceneKey, 41 42 /** 43 * The keys to all overlays in the container, sorted by z-order such that the last one renders 44 * on top of all previous ones. Overlay keys within the same container must not repeat but it's 45 * okay to have the same overlay keys in different containers. 46 */ 47 val overlayKeys: List<OverlayKey> = emptyList(), 48 49 /** 50 * Navigation distance of each scene. 51 * 52 * The navigation distance is a measure of how many non-back user action "steps" away from the 53 * starting scene, each scene is. 54 * 55 * The framework uses these to help scene implementations decide which scene to go back to when 56 * the user attempts to navigate back on them, if they need that. 57 * 58 * In general, the more non-back user actions are needed to get to a scene, the greater that 59 * scene's distance should be. Navigating "back" then goes from scenes with a higher distance to 60 * scenes with a lower distance. 61 * 62 * Note that this is not the z-order of rendering; that's determined by the order of declaration 63 * of scenes in the [sceneKeys] list. 64 */ 65 val navigationDistances: Map<SceneKey, Int>, 66 67 /** 68 * Builds the comprehensive definition of all transitions between scenes and overlays in the 69 * scene container. 70 */ 71 val transitionsBuilder: SceneContainerTransitionsBuilder, 72 ) { 73 init { <lambda>null74 check(sceneKeys.isNotEmpty()) { "A container must have at least one scene key." } 75 <lambda>null76 check(sceneKeys.contains(initialSceneKey)) { 77 "The initial key \"$initialSceneKey\" is not present in this container." 78 } 79 <lambda>null80 check(navigationDistances.keys == sceneKeys.toSet()) { 81 "Scene keys and distance map must match." 82 } 83 } 84 } 85