[flexiglass] Composables for scenes and scene container.

Implements the composable functions for scene placeholders and the scene
container, which itself, is a placeholder. Instead of handling true
swipes and real UI, the placeholders have buttons for triggering a swipe
event and no transition animations between scenes. This entire system is
meant purely for testing the scene switching logic in previous CLs in
the Compose Gallery playground app.

Bug: 279501596
Test: Manually verified all scene transitions using the testbed app.
Change-Id: I4b81988b2ea6ef5388714674718e2f742dd1b3a4

packages/SystemUI/compose/facade/disabled/src/com/android/systemui/scene/shared/page/SceneModule.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.scene.shared.page
+
+import com.android.systemui.scene.shared.model.Scene
+import dagger.Module
+import dagger.multibindings.Multibinds
+
+@Module
+interface SceneModule {
+    @Multibinds fun scenes(): Set<Scene>
+}

packages/SystemUI/compose/facade/enabled/src/com/android/systemui/scene/ui/composable/SceneModule.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.scene.ui.composable
+
+import com.android.systemui.bouncer.ui.composable.BouncerScene
+import com.android.systemui.keyguard.ui.composable.LockScreenScene
+import com.android.systemui.qs.ui.composable.QuickSettingsScene
+import com.android.systemui.scene.shared.model.Scene
+import com.android.systemui.shade.ui.composable.ShadeScene
+import dagger.Module
+import dagger.Provides
+
+@Module
+object SceneModule {
+    @Provides
+    fun scenes(
+        bouncer: BouncerScene,
+        gone: GoneScene,
+        lockScreen: LockScreenScene,
+        qs: QuickSettingsScene,
+        shade: ShadeScene,
+    ): Set<Scene> {
+        return setOf(
+            bouncer,
+            gone,
+            lockScreen,
+            qs,
+            shade,
+        )
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/bouncer/ui/composable/BouncerScene.kt

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.bouncer.ui.composable
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.Button
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.android.systemui.bouncer.ui.viewmodel.BouncerViewModel
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import com.android.systemui.scene.ui.composable.ComposableScene
+import javax.inject.Inject
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/** The bouncer scene displays authentication challenges like PIN, password, or pattern. */
+@SysUISingleton
+class BouncerScene
+@Inject
+constructor(
+    private val viewModel: BouncerViewModel,
+) : ComposableScene {
+    override val key = SceneKey.Bouncer
+
+    override fun destinationScenes(): StateFlow<Map<UserAction, SceneModel>> =
+        MutableStateFlow<Map<UserAction, SceneModel>>(
+                mapOf(
+                    UserAction.Back to SceneModel(SceneKey.LockScreen),
+                )
+            )
+            .asStateFlow()
+
+    @Composable
+    override fun Content(
+        modifier: Modifier,
+    ) {
+        // TODO(b/280877228): implement the real UI.
+
+        Box(modifier = modifier) {
+            Column(
+                horizontalAlignment = Alignment.CenterHorizontally,
+                modifier = Modifier.align(Alignment.Center)
+            ) {
+                Text("Bouncer", style = MaterialTheme.typography.headlineLarge)
+                Row(
+                    horizontalArrangement = Arrangement.spacedBy(8.dp),
+                ) {
+                    Button(onClick = { viewModel.onAuthenticateButtonClicked() }) {
+                        Text("Authenticate")
+                    }
+                }
+            }
+        }
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/keyguard/ui/composable/LockScreenScene.kt

@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.keyguard.ui.composable
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.Button
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.android.systemui.common.shared.model.Icon
+import com.android.systemui.common.ui.compose.Icon
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.keyguard.ui.viewmodel.LockScreenSceneViewModel
+import com.android.systemui.scene.shared.model.Direction
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import com.android.systemui.scene.ui.composable.ComposableScene
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+
+/** The lock screen scene shows when the device is locked. */
+@SysUISingleton
+class LockScreenScene
+@Inject
+constructor(
+    @Application private val applicationScope: CoroutineScope,
+    private val viewModel: LockScreenSceneViewModel,
+) : ComposableScene {
+    override val key = SceneKey.LockScreen
+
+    override fun destinationScenes(): StateFlow<Map<UserAction, SceneModel>> =
+        viewModel.upDestinationSceneKey
+            .map { pageKey -> destinationScenes(up = pageKey) }
+            .stateIn(
+                scope = applicationScope,
+                started = SharingStarted.Eagerly,
+                initialValue = destinationScenes(up = viewModel.upDestinationSceneKey.value)
+            )
+
+    @Composable
+    override fun Content(
+        modifier: Modifier,
+    ) {
+        LockScreenScene(
+            viewModel = viewModel,
+            modifier = modifier,
+        )
+    }
+
+    private fun destinationScenes(
+        up: SceneKey,
+    ): Map<UserAction, SceneModel> {
+        return mapOf(
+            UserAction.Swipe(Direction.UP) to SceneModel(up),
+            UserAction.Swipe(Direction.DOWN) to SceneModel(SceneKey.Shade)
+        )
+    }
+}
+
+@Composable
+private fun LockScreenScene(
+    viewModel: LockScreenSceneViewModel,
+    modifier: Modifier = Modifier,
+) {
+    // TODO(b/280879610): implement the real UI.
+
+    val lockButtonIcon: Icon by viewModel.lockButtonIcon.collectAsState()
+
+    Box(modifier = modifier) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = Modifier.align(Alignment.Center)
+        ) {
+            Text("Lock screen", style = MaterialTheme.typography.headlineMedium)
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                Button(onClick = { viewModel.onLockButtonClicked() }) { Icon(lockButtonIcon) }
+
+                Button(onClick = { viewModel.onContentClicked() }) { Text("Open some content") }
+            }
+        }
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/qs/ui/composable/QuickSettingsScene.kt

@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.qs.ui.composable
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.Button
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.qs.ui.viewmodel.QuickSettingsSceneViewModel
+import com.android.systemui.scene.shared.model.Direction
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import com.android.systemui.scene.ui.composable.ComposableScene
+import javax.inject.Inject
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/** The Quick Settings (AKA "QS") scene shows the quick setting tiles. */
+@SysUISingleton
+class QuickSettingsScene
+@Inject
+constructor(
+    private val viewModel: QuickSettingsSceneViewModel,
+) : ComposableScene {
+    override val key = SceneKey.QuickSettings
+
+    override fun destinationScenes(): StateFlow<Map<UserAction, SceneModel>> =
+        MutableStateFlow<Map<UserAction, SceneModel>>(
+                mapOf(
+                    UserAction.Swipe(Direction.UP) to SceneModel(SceneKey.Shade),
+                )
+            )
+            .asStateFlow()
+
+    @Composable
+    override fun Content(
+        modifier: Modifier,
+    ) {
+        QuickSettingsScene(
+            viewModel = viewModel,
+            modifier = modifier,
+        )
+    }
+}
+
+@Composable
+private fun QuickSettingsScene(
+    viewModel: QuickSettingsSceneViewModel,
+    modifier: Modifier = Modifier,
+) {
+    // TODO(b/280887232): implement the real UI.
+
+    Box(modifier = modifier) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = Modifier.align(Alignment.Center)
+        ) {
+            Text("Quick settings", style = MaterialTheme.typography.headlineMedium)
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                Button(onClick = { viewModel.onContentClicked() }) { Text("Open some content") }
+            }
+        }
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/scene/ui/composable/ComposableScene.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.scene.ui.composable
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import com.android.systemui.scene.shared.model.Scene
+
+/** Compose-capable extension of [Scene]. */
+interface ComposableScene : Scene {
+    @Composable fun Content(modifier: Modifier)
+}

packages/SystemUI/compose/features/src/com/android/systemui/scene/ui/composable/GoneScene.kt

@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.scene.ui.composable
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.scene.shared.model.Direction
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import javax.inject.Inject
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/**
+ * "Gone" is not a real scene but rather the absence of scenes when we want to skip showing any
+ * content from the scene framework.
+ */
+@SysUISingleton
+class GoneScene @Inject constructor() : ComposableScene {
+    override val key = SceneKey.Gone
+
+    override fun destinationScenes(): StateFlow<Map<UserAction, SceneModel>> =
+        MutableStateFlow<Map<UserAction, SceneModel>>(
+                mapOf(
+                    UserAction.Swipe(Direction.DOWN) to SceneModel(SceneKey.Shade),
+                )
+            )
+            .asStateFlow()
+
+    @Composable
+    override fun Content(
+        modifier: Modifier,
+    ) {
+        /*
+         * TODO(b/279501596): once we start testing with the real Content Dynamics Framework,
+         *  replace this with an error to make sure it doesn't get rendered.
+         */
+        Box(modifier = modifier) {
+            Column(
+                horizontalAlignment = Alignment.CenterHorizontally,
+                modifier = Modifier.align(Alignment.Center)
+            ) {
+                Text("Gone", style = MaterialTheme.typography.headlineMedium)
+            }
+        }
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/scene/ui/composable/SceneContainer.kt

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2023 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:OptIn(ExperimentalAnimationApi::class)
+
+package com.android.systemui.scene.ui.composable
+
+import androidx.activity.compose.BackHandler
+import androidx.compose.animation.AnimatedContent
+import androidx.compose.animation.ExperimentalAnimationApi
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.material3.Button
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.android.systemui.scene.shared.model.Direction
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import com.android.systemui.scene.ui.viewmodel.SceneContainerViewModel
+import java.util.Locale
+
+/**
+ * Renders a container of a collection of "scenes" that the user can switch between using certain
+ * user actions (for instance, swiping up and down) or that can be switched automatically based on
+ * application business logic in response to certain events (for example, the device unlocking).
+ *
+ * It's possible for the application to host several such scene containers, the configuration system
+ * allows configuring each container with its own set of scenes. Scenes can be present in multiple
+ * containers.
+ *
+ * @param viewModel The UI state holder for this container.
+ * @param sceneByKey Mapping of [ComposableScene] by [SceneKey], ordered by z-order such that the
+ *   last scene is rendered on top of all other scenes. It's critical that this map contains exactly
+ *   and only the scenes on this container. In other words: (a) there should be no scene in this map
+ *   that is not in the configuration for this container and (b) all scenes in the configuration
+ *   must have entries in this map.
+ * @param modifier A modifier.
+ */
+@Composable
+fun SceneContainer(
+    viewModel: SceneContainerViewModel,
+    sceneByKey: Map<SceneKey, ComposableScene>,
+    modifier: Modifier = Modifier,
+) {
+    val currentScene: SceneModel by viewModel.currentScene.collectAsState()
+
+    AnimatedContent(
+        targetState = currentScene.key,
+        label = "scene container",
+        modifier = modifier,
+    ) { currentSceneKey ->
+        sceneByKey.forEach { (key, composableScene) ->
+            if (key == currentSceneKey) {
+                Scene(
+                    scene = composableScene,
+                    onSceneChanged = viewModel::setCurrentScene,
+                    modifier = Modifier.fillMaxSize(),
+                )
+            }
+        }
+    }
+}
+
+/** Renders the given [ComposableScene]. */
+@Composable
+private fun Scene(
+    scene: ComposableScene,
+    onSceneChanged: (SceneModel) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    // TODO(b/280880714): replace with the real UI and make sure to call onTransitionProgress.
+    Box(modifier) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = Modifier.align(Alignment.Center),
+        ) {
+            scene.Content(
+                modifier = Modifier,
+            )
+
+            val destinationScenes: Map<UserAction, SceneModel> by
+                scene.destinationScenes().collectAsState()
+            val swipeLeftDestinationScene = destinationScenes[UserAction.Swipe(Direction.LEFT)]
+            val swipeUpDestinationScene = destinationScenes[UserAction.Swipe(Direction.UP)]
+            val swipeRightDestinationScene = destinationScenes[UserAction.Swipe(Direction.RIGHT)]
+            val swipeDownDestinationScene = destinationScenes[UserAction.Swipe(Direction.DOWN)]
+            val backDestinationScene = destinationScenes[UserAction.Back]
+
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                DirectionalButton(Direction.LEFT, swipeLeftDestinationScene, onSceneChanged)
+                DirectionalButton(Direction.UP, swipeUpDestinationScene, onSceneChanged)
+                DirectionalButton(Direction.RIGHT, swipeRightDestinationScene, onSceneChanged)
+                DirectionalButton(Direction.DOWN, swipeDownDestinationScene, onSceneChanged)
+            }
+
+            if (backDestinationScene != null) {
+                BackHandler { onSceneChanged.invoke(backDestinationScene) }
+            }
+        }
+    }
+}
+
+@Composable
+private fun DirectionalButton(
+    direction: Direction,
+    destinationScene: SceneModel?,
+    onSceneChanged: (SceneModel) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Button(
+        onClick = { destinationScene?.let { onSceneChanged.invoke(it) } },
+        enabled = destinationScene != null,
+        modifier = modifier,
+    ) {
+        Text(direction.name.lowercase(Locale.getDefault()))
+    }
+}

packages/SystemUI/compose/features/src/com/android/systemui/shade/ui/composable/ShadeScene.kt

@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.shade.ui.composable
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.Button
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.scene.shared.model.Direction
+import com.android.systemui.scene.shared.model.SceneKey
+import com.android.systemui.scene.shared.model.SceneModel
+import com.android.systemui.scene.shared.model.UserAction
+import com.android.systemui.scene.ui.composable.ComposableScene
+import com.android.systemui.shade.ui.viewmodel.ShadeSceneViewModel
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+
+/** The shade scene shows scrolling list of notifications and some of the quick setting tiles. */
+@SysUISingleton
+class ShadeScene
+@Inject
+constructor(
+    @Application private val applicationScope: CoroutineScope,
+    private val viewModel: ShadeSceneViewModel,
+) : ComposableScene {
+    override val key = SceneKey.Shade
+
+    override fun destinationScenes(): StateFlow<Map<UserAction, SceneModel>> =
+        viewModel.upDestinationSceneKey
+            .map { sceneKey -> destinationScenes(up = sceneKey) }
+            .stateIn(
+                scope = applicationScope,
+                started = SharingStarted.Eagerly,
+                initialValue = destinationScenes(up = viewModel.upDestinationSceneKey.value),
+            )
+
+    @Composable
+    override fun Content(
+        modifier: Modifier,
+    ) {
+        ShadeScene(
+            viewModel = viewModel,
+            modifier = modifier,
+        )
+    }
+
+    private fun destinationScenes(
+        up: SceneKey,
+    ): Map<UserAction, SceneModel> {
+        return mapOf(
+            UserAction.Swipe(Direction.UP) to SceneModel(up),
+            UserAction.Swipe(Direction.DOWN) to SceneModel(SceneKey.QuickSettings),
+        )
+    }
+}
+
+@Composable
+private fun ShadeScene(
+    viewModel: ShadeSceneViewModel,
+    modifier: Modifier = Modifier,
+) {
+    // TODO(b/280887022): implement the real UI.
+
+    Box(modifier = modifier) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = Modifier.align(Alignment.Center)
+        ) {
+            Text("Shade", style = MaterialTheme.typography.headlineMedium)
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                Button(
+                    onClick = { viewModel.onContentClicked() },
+                ) {
+                    Text("Open some content")
+                }
+            }
+        }
+    }
+}

packages/SystemUI/src/com/android/systemui/dagger/ReferenceSystemUIModule.java

@@ -42,6 +42,7 @@ import com.android.systemui.qs.tileimpl.QSFactoryImpl;
 import com.android.systemui.recents.Recents;
 import com.android.systemui.recents.RecentsImplementation;
 import com.android.systemui.rotationlock.RotationLockModule;
+import com.android.systemui.scene.SceneContainerFrameworkModule;
 import com.android.systemui.screenshot.ReferenceScreenshotModule;
 import com.android.systemui.settings.dagger.MultiUserUtilsModule;
 import com.android.systemui.shade.NotificationShadeWindowControllerImpl;
@@ -74,12 +75,12 @@ import com.android.systemui.statusbar.policy.SensorPrivacyController;
 import com.android.systemui.statusbar.policy.SensorPrivacyControllerImpl;
 import com.android.systemui.volume.dagger.VolumeModule;
 
-import javax.inject.Named;
-
 import dagger.Binds;
 import dagger.Module;
 import dagger.Provides;
 
+import javax.inject.Named;
+
 /**
  * A dagger module for injecting default implementations of components of System UI.
  *
@@ -105,6 +106,7 @@ import dagger.Provides;
         QSModule.class,
         ReferenceScreenshotModule.class,
         RotationLockModule.class,
+        SceneContainerFrameworkModule.class,
         StatusBarEventsModule.class,
         StartCentralSurfacesModule.class,
         VolumeModule.class,

packages/SystemUI/src/com/android/systemui/scene/SceneContainerFrameworkModule.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package com.android.systemui.scene
+
+import com.android.systemui.scene.shared.page.SceneModule
+import dagger.Module
+
+@Module(
+    includes =
+        [
+            SceneModule::class,
+        ],
+)
+object SceneContainerFrameworkModule