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Commit 6078c273 authored by Fabián Kozynski's avatar Fabián Kozynski
Browse files

Add media to QSFragmentCompose 

This adds a basic media composable that tracks the visibility of the
host. Because the transitions between the hosts are handled by
QuickSettingsControllerImpl, there's nothing that needs to be done for
it.

The following has not been implemented yet:

* Proper clipping when expanding above FooterActions
* Proper padding and positioning for animations
* Media squishiness
* Landscape media

Test: atest QSFragmentComposeViewModelTest
Test: atest android.platform.test.scenario.sysui.media
Bug: 353253280
Fixes: 373580826
Flag: com.android.systemui.qs_ui_refactor_compose_fragment

Change-Id: I900f5393458d0b58d6ed28cc47260bd3f54b236d
parent cfe2434e

packages/SystemUI/multivalentTests/src/com/android/systemui/qs/composefragment/viewmodel/AbstractQSFragmentComposeViewModelTest.kt

+10 −2
Original line number Diff line number Diff line
@@ -24,12 +24,16 @@ import com.android.systemui.SysuiTestCase 
import com.android.systemui.kosmos.testDispatcher

import com.android.systemui.kosmos.testScope

import com.android.systemui.lifecycle.activateIn

import com.android.systemui.media.controls.domain.pipeline.legacyMediaDataManagerImpl

import com.android.systemui.media.controls.domain.pipeline.mediaDataManager

import com.android.systemui.qs.composefragment.dagger.usingMediaInComposeFragment

import com.android.systemui.testKosmos

import kotlinx.coroutines.Dispatchers

import kotlinx.coroutines.ExperimentalCoroutinesApi

import kotlinx.coroutines.test.TestResult

import kotlinx.coroutines.test.TestScope

import kotlinx.coroutines.test.resetMain

import kotlinx.coroutines.test.runCurrent

import kotlinx.coroutines.test.runTest

import kotlinx.coroutines.test.setMain

import org.junit.After
@@ -39,7 +43,7 @@ import org.junit.runner.RunWith 
@RunWith(AndroidJUnit4::class)

@OptIn(ExperimentalCoroutinesApi::class)

abstract class AbstractQSFragmentComposeViewModelTest : SysuiTestCase() {

    protected val kosmos = testKosmos()

    protected val kosmos = testKosmos().apply { mediaDataManager = legacyMediaDataManagerImpl }



    protected val lifecycleOwner =

        TestLifecycleOwner(
@@ -62,11 +66,15 @@ abstract class AbstractQSFragmentComposeViewModelTest : SysuiTestCase() { 
    }



    protected inline fun TestScope.testWithinLifecycle(

        crossinline block: suspend TestScope.() -> TestResult

        usingMedia: Boolean = true,

        crossinline block: suspend TestScope.() -> TestResult,

    ): TestResult {

        return runTest {

            kosmos.usingMediaInComposeFragment = usingMedia



            lifecycleOwner.setCurrentState(Lifecycle.State.RESUMED)

            underTest.activateIn(kosmos.testScope)

            runCurrent()

            block().also { lifecycleOwner.setCurrentState(Lifecycle.State.DESTROYED) }

        }

    }

packages/SystemUI/multivalentTests/src/com/android/systemui/qs/composefragment/viewmodel/QSFragmentComposeViewModelTest.kt

+103 −0
Original line number Diff line number Diff line
@@ -25,6 +25,15 @@ import androidx.test.filters.SmallTest 
import com.android.systemui.common.ui.data.repository.fakeConfigurationRepository

import com.android.systemui.coroutines.collectLastValue

import com.android.systemui.kosmos.testScope

import com.android.systemui.media.controls.domain.pipeline.legacyMediaDataManagerImpl

import com.android.systemui.media.controls.ui.controller.MediaHierarchyManager

import com.android.systemui.media.controls.ui.controller.mediaCarouselController

import com.android.systemui.media.controls.ui.view.MediaHostState

import com.android.systemui.media.controls.ui.view.qqsMediaHost

import com.android.systemui.media.controls.ui.view.qsMediaHost

import com.android.systemui.qs.composefragment.viewmodel.MediaState.ACTIVE_MEDIA

import com.android.systemui.qs.composefragment.viewmodel.MediaState.ANY_MEDIA

import com.android.systemui.qs.composefragment.viewmodel.MediaState.NO_MEDIA

import com.android.systemui.qs.fgsManagerController

import com.android.systemui.qs.panels.domain.interactor.tileSquishinessInteractor

import com.android.systemui.res.R
@@ -35,9 +44,11 @@ import com.android.systemui.statusbar.disableflags.data.repository.fakeDisableFl 
import com.android.systemui.statusbar.sysuiStatusBarStateController

import com.google.common.truth.Truth.assertThat

import kotlinx.coroutines.ExperimentalCoroutinesApi

import kotlinx.coroutines.test.TestScope

import kotlinx.coroutines.test.runCurrent

import org.junit.Test

import org.junit.runner.RunWith

import org.mockito.kotlin.whenever



@SmallTest

@RunWith(AndroidJUnit4::class)
@@ -185,6 +196,92 @@ class QSFragmentComposeViewModelTest : AbstractQSFragmentComposeViewModelTest() 
            }

        }



    @Test

    fun qqsMediaHost_initializedCorrectly() =

        with(kosmos) {

            testScope.testWithinLifecycle {

                assertThat(underTest.qqsMediaHost.location)

                    .isEqualTo(MediaHierarchyManager.LOCATION_QQS)

                assertThat(underTest.qqsMediaHost.expansion).isEqualTo(MediaHostState.EXPANDED)

                assertThat(underTest.qqsMediaHost.showsOnlyActiveMedia).isTrue()

                assertThat(underTest.qqsMediaHost.hostView).isNotNull()

            }

        }



    @Test

    fun qsMediaHost_initializedCorrectly() =

        with(kosmos) {

            testScope.testWithinLifecycle {

                assertThat(underTest.qsMediaHost.location)

                    .isEqualTo(MediaHierarchyManager.LOCATION_QS)

                assertThat(underTest.qsMediaHost.expansion).isEqualTo(MediaHostState.EXPANDED)

                assertThat(underTest.qsMediaHost.showsOnlyActiveMedia).isFalse()

                assertThat(underTest.qsMediaHost.hostView).isNotNull()

            }

        }



    @Test

    fun qqsMediaVisible_onlyWhenActiveMedia() =

        with(kosmos) {

            testScope.testWithinLifecycle {

                whenever(mediaCarouselController.isLockedAndHidden()).thenReturn(false)



                assertThat(underTest.qqsMediaVisible).isEqualTo(underTest.qqsMediaHost.visible)



                setMediaState(NO_MEDIA)

                assertThat(underTest.qqsMediaVisible).isFalse()



                setMediaState(ANY_MEDIA)

                assertThat(underTest.qqsMediaVisible).isFalse()



                setMediaState(ACTIVE_MEDIA)

                assertThat(underTest.qqsMediaVisible).isTrue()

            }

        }



    @Test

    fun qsMediaVisible_onAnyMedia() =

        with(kosmos) {

            testScope.testWithinLifecycle {

                whenever(mediaCarouselController.isLockedAndHidden()).thenReturn(false)



                assertThat(underTest.qsMediaVisible).isEqualTo(underTest.qsMediaHost.visible)



                setMediaState(NO_MEDIA)

                assertThat(underTest.qsMediaVisible).isFalse()



                setMediaState(ANY_MEDIA)

                assertThat(underTest.qsMediaVisible).isTrue()



                setMediaState(ACTIVE_MEDIA)

                assertThat(underTest.qsMediaVisible).isTrue()

            }

        }



    @Test

    fun notUsingMedia_mediaNotVisible() =

        with(kosmos) {

            testScope.testWithinLifecycle(usingMedia = false) {

                setMediaState(ACTIVE_MEDIA)



                assertThat(underTest.qqsMediaVisible).isFalse()

                assertThat(underTest.qsMediaVisible).isFalse()

            }

        }



    private fun TestScope.setMediaState(state: MediaState) {

        with(kosmos) {

            val activeMedia = state == ACTIVE_MEDIA

            val anyMedia = state != NO_MEDIA

            whenever(legacyMediaDataManagerImpl.hasActiveMediaOrRecommendation())

                .thenReturn(activeMedia)

            whenever(legacyMediaDataManagerImpl.hasAnyMediaOrRecommendation()).thenReturn(anyMedia)

            qqsMediaHost.updateViewVisibility()

            qsMediaHost.updateViewVisibility()

        }

        runCurrent()

    }



    companion object {

        private const val QS_DISABLE_FLAG = StatusBarManager.DISABLE2_QUICK_SETTINGS
@@ -195,3 +292,9 @@ class QSFragmentComposeViewModelTest : AbstractQSFragmentComposeViewModelTest() 
        private const val epsilon = 0.001f

    }

}



private enum class MediaState {

    ACTIVE_MEDIA,

    ANY_MEDIA,

    NO_MEDIA,

}

packages/SystemUI/src/com/android/systemui/qs/composefragment/QSFragmentCompose.kt

+65 −16
Original line number Diff line number Diff line
@@ -38,12 +38,14 @@ import androidx.compose.animation.fadeIn 
import androidx.compose.animation.fadeOut

import androidx.compose.animation.togetherWith

import androidx.compose.foundation.ScrollState

import androidx.compose.foundation.layout.Arrangement.spacedBy

import androidx.compose.foundation.layout.Box

import androidx.compose.foundation.layout.Column

import androidx.compose.foundation.layout.Spacer

import androidx.compose.foundation.layout.WindowInsets

import androidx.compose.foundation.layout.fillMaxSize

import androidx.compose.foundation.layout.fillMaxWidth

import androidx.compose.foundation.layout.height

import androidx.compose.foundation.layout.navigationBars

import androidx.compose.foundation.layout.offset

import androidx.compose.foundation.layout.windowInsetsPadding
@@ -73,13 +75,14 @@ import androidx.compose.ui.semantics.CustomAccessibilityAction 
import androidx.compose.ui.semantics.customActions

import androidx.compose.ui.semantics.semantics

import androidx.compose.ui.unit.IntOffset

import androidx.compose.ui.unit.dp

import androidx.compose.ui.unit.round

import androidx.compose.ui.util.fastRoundToInt

import androidx.compose.ui.viewinterop.AndroidView

import androidx.lifecycle.Lifecycle

import androidx.lifecycle.compose.collectAsStateWithLifecycle

import androidx.lifecycle.lifecycleScope

import androidx.lifecycle.repeatOnLifecycle

import com.android.app.tracing.coroutines.launchTraced as launch

import com.android.compose.animation.scene.ContentKey

import com.android.compose.animation.scene.ElementKey

import com.android.compose.animation.scene.ElementMatcher
@@ -98,10 +101,7 @@ import com.android.systemui.compose.modifiers.sysuiResTag 
import com.android.systemui.dump.DumpManager

import com.android.systemui.lifecycle.repeatWhenAttached

import com.android.systemui.lifecycle.setSnapshotBinding

import com.android.systemui.media.controls.ui.controller.MediaHierarchyManager

import com.android.systemui.media.controls.ui.view.MediaHost

import com.android.systemui.media.dagger.MediaModule.QS_PANEL

import com.android.systemui.media.dagger.MediaModule.QUICK_QS_PANEL

import com.android.systemui.plugins.qs.QS

import com.android.systemui.plugins.qs.QSContainerController

import com.android.systemui.qs.composefragment.SceneKeys.QuickQuickSettings
@@ -127,7 +127,6 @@ import com.android.systemui.util.println 
import java.io.PrintWriter

import java.util.function.Consumer

import javax.inject.Inject

import javax.inject.Named

import kotlinx.coroutines.CompletableDeferred

import kotlinx.coroutines.awaitCancellation

import kotlinx.coroutines.coroutineScope
@@ -135,6 +134,7 @@ import kotlinx.coroutines.flow.Flow 
import kotlinx.coroutines.flow.MutableStateFlow

import kotlinx.coroutines.flow.collectLatest

import kotlinx.coroutines.flow.map

import kotlinx.coroutines.launch



@SuppressLint("ValidFragment")

class QSFragmentCompose
@@ -142,11 +142,11 @@ class QSFragmentCompose 
constructor(

    private val qsFragmentComposeViewModelFactory: QSFragmentComposeViewModel.Factory,

    private val dumpManager: DumpManager,

    @Named(QUICK_QS_PANEL) private val qqsMediaHost: MediaHost,

    @Named(QS_PANEL) private val qsMediaHost: MediaHost,

) : LifecycleFragment(), QS, Dumpable {



    private val scrollListener = MutableStateFlow<QS.ScrollListener?>(null)

    private val collapsedMediaVisibilityChangedListener =

        MutableStateFlow<(Consumer<Boolean>)?>(null)

    private val heightListener = MutableStateFlow<QS.HeightListener?>(null)

    private val qsContainerController = MutableStateFlow<QSContainerController?>(null)
@@ -183,8 +183,6 @@ constructor( 
        QSComposeFragment.isUnexpectedlyInLegacyMode()

        viewModel = qsFragmentComposeViewModelFactory.create(lifecycleScope)



        qqsMediaHost.init(MediaHierarchyManager.LOCATION_QQS)

        qsMediaHost.init(MediaHierarchyManager.LOCATION_QS)

        setListenerCollections()

        lifecycleScope.launch { viewModel.activate() }

    }
@@ -491,7 +489,7 @@ constructor( 
    }



    override fun setCollapsedMediaVisibilityChangedListener(listener: Consumer<Boolean>?) {

        // TODO (b/353253280)

        collapsedMediaVisibilityChangedListener.value = listener

    }



    override fun setScrollListener(scrollListener: QS.ScrollListener?) {
@@ -534,6 +532,7 @@ constructor( 
            lifecycle.repeatOnLifecycle(Lifecycle.State.STARTED) {

                this@QSFragmentCompose.view?.setSnapshotBinding {

                    scrollListener.value?.onQsPanelScrollChanged(scrollState.value)

                    collapsedMediaVisibilityChangedListener.value?.accept(viewModel.qqsMediaVisible)

                }

                launch {

                    setListenerJob(
@@ -569,7 +568,7 @@ constructor( 
                .squishiness

                .collectAsStateWithLifecycle()



        Column(modifier = Modifier.sysuiResTag("quick_qs_panel")) {

        Column(modifier = Modifier.sysuiResTag(ResIdTags.quickQsPanel)) {

            Box(

                modifier =

                    Modifier.fillMaxWidth()
@@ -581,6 +580,9 @@ constructor( 
                                leftFromRoot + coordinates.size.width,

                                topFromRoot + coordinates.size.height,

                            )

                            if (squishiness == 1f) {

                                viewModel.qqsHeight = coordinates.size.height

                            }

                        }

                        // Use an approach layout to determien the height without squishiness, as

                        // that's the value that NPVC and QuickSettingsController care about
@@ -595,8 +597,7 @@ constructor( 
                        .padding(top = { qqsPadding }, bottom = { bottomPadding })

            ) {

                if (viewModel.isQsEnabled) {

                    QuickQuickSettings(

                        viewModel = viewModel.containerViewModel.quickQuickSettingsViewModel,

                    Column(

                        modifier =

                            Modifier.collapseExpandSemanticAction(

                                    stringResource(
@@ -608,7 +609,16 @@ constructor( 
                                        QuickSettingsShade.Dimensions.Padding.roundToPx()

                                    }

                                ),

                        verticalArrangement =

                            spacedBy(dimensionResource(R.dimen.qs_tile_margin_vertical)),

                    ) {

                        QuickQuickSettings(

                            viewModel = viewModel.containerViewModel.quickQuickSettingsViewModel

                        )

                        if (viewModel.qqsMediaVisible) {

                            MediaObject(mediaHost = viewModel.qqsMediaHost)

                        }

                    }

                }

            }

            Spacer(modifier = Modifier.weight(1f))
@@ -645,22 +655,35 @@ constructor( 
                                }

                                .onSizeChanged { viewModel.qsScrollHeight = it.height }

                                .verticalScroll(scrollState)

                                .sysuiResTag(ResIdTags.qsScroll)

                    ) {

                        Spacer(

                            modifier = Modifier.height { qqsPadding + qsExtraPadding.roundToPx() }

                        )

                        QuickSettingsLayout(

                            viewModel = viewModel.containerViewModel,

                            modifier = Modifier.sysuiResTag("quick_settings_panel"),

                            modifier = Modifier.sysuiResTag(ResIdTags.quickSettingsPanel),

                        )

                        Spacer(modifier = Modifier.height(8.dp))

                        if (viewModel.qsMediaVisible) {

                            MediaObject(

                                mediaHost = viewModel.qsMediaHost,

                                modifier =

                                    Modifier.padding(

                                        horizontal = {

                                            QuickSettingsShade.Dimensions.Padding.roundToPx()

                                        }

                                    ),

                            )

                        }

                    }

                }

                QuickSettingsTheme {

                    FooterActions(

                        viewModel = viewModel.footerActionsViewModel,

                        qsVisibilityLifecycleOwner = this@QSFragmentCompose,

                        modifier =

                            Modifier.sysuiResTag("qs_footer_actions")

                            Modifier.sysuiResTag(ResIdTags.qsFooterActions)

                                .element(ElementKeys.FooterActions),

                    )

                }
@@ -914,3 +937,29 @@ private fun Modifier.gesturesDisabled(disabled: Boolean) = 
    } else {

        this

    }



@Composable

private fun MediaObject(mediaHost: MediaHost, modifier: Modifier = Modifier) {

    Box {

        AndroidView(

            modifier = modifier,

            factory = {

                mediaHost.hostView.apply {

                    layoutParams =

                        FrameLayout.LayoutParams(

                            FrameLayout.LayoutParams.MATCH_PARENT,

                            FrameLayout.LayoutParams.WRAP_CONTENT,

                        )

                }

            },

            onReset = {},

        )

    }

}



private object ResIdTags {

    const val quickSettingsPanel = "quick_settings_panel"

    const val quickQsPanel = "quick_qs_panel"

    const val qsScroll = "expanded_qs_scroll_view"

    const val qsFooterActions = "qs_footer_actions"

}

packages/SystemUI/src/com/android/systemui/qs/composefragment/dagger/QSFragmentComposeModule.kt

0 → 100644
+40 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2024 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.composefragment.dagger



import android.content.Context

import com.android.systemui.dagger.SysUISingleton

import com.android.systemui.dagger.qualifiers.Application

import com.android.systemui.util.Utils

import dagger.Module

import dagger.Provides

import javax.inject.Named



@Module

interface QSFragmentComposeModule {



    companion object {

        const val QS_USING_MEDIA_PLAYER = "compose_fragment_using_media_player"



        @Provides

        @SysUISingleton

        @Named(QS_USING_MEDIA_PLAYER)

        fun providesUsingMedia(@Application context: Context): Boolean {

            return Utils.useQsMediaPlayer(context)

        }

    }

}

packages/SystemUI/src/com/android/systemui/qs/composefragment/viewmodel/QSFragmentComposeViewModel.kt

+73 −3
Original line number Diff line number Diff line
@@ -38,8 +38,14 @@ import com.android.systemui.keyguard.shared.model.Edge 
import com.android.systemui.keyguard.shared.model.KeyguardState

import com.android.systemui.lifecycle.ExclusiveActivatable

import com.android.systemui.lifecycle.Hydrator

import com.android.systemui.media.controls.ui.controller.MediaHierarchyManager

import com.android.systemui.media.controls.ui.view.MediaHost

import com.android.systemui.media.controls.ui.view.MediaHostState

import com.android.systemui.media.dagger.MediaModule.QS_PANEL

import com.android.systemui.media.dagger.MediaModule.QUICK_QS_PANEL

import com.android.systemui.plugins.statusbar.StatusBarStateController

import com.android.systemui.qs.FooterActionsController

import com.android.systemui.qs.composefragment.dagger.QSFragmentComposeModule

import com.android.systemui.qs.footer.ui.viewmodel.FooterActionsViewModel

import com.android.systemui.qs.panels.domain.interactor.TileSquishinessInteractor

import com.android.systemui.qs.panels.ui.viewmodel.PaginatedGridViewModel
@@ -60,10 +66,14 @@ import dagger.assisted.Assisted 
import dagger.assisted.AssistedFactory

import dagger.assisted.AssistedInject

import java.io.PrintWriter

import javax.inject.Named

import kotlinx.coroutines.ExperimentalCoroutinesApi

import kotlinx.coroutines.awaitCancellation

import kotlinx.coroutines.channels.awaitClose

import kotlinx.coroutines.coroutineScope

import kotlinx.coroutines.flow.Flow

import kotlinx.coroutines.flow.callbackFlow

import kotlinx.coroutines.flow.flowOf

import kotlinx.coroutines.flow.map

import kotlinx.coroutines.flow.onStart
@@ -84,6 +94,9 @@ constructor( 
    private val largeScreenHeaderHelper: LargeScreenHeaderHelper,

    private val squishinessInteractor: TileSquishinessInteractor,

    private val paginatedGridViewModel: PaginatedGridViewModel,

    @Named(QUICK_QS_PANEL) val qqsMediaHost: MediaHost,

    @Named(QS_PANEL) val qsMediaHost: MediaHost,

    @Named(QSFragmentComposeModule.QS_USING_MEDIA_PLAYER) private val usingMedia: Boolean,

    @Assisted private val lifecycleScope: LifecycleCoroutineScope,

) : Dumpable, ExclusiveActivatable() {
@@ -222,6 +235,30 @@ constructor( 
        }

    }



    val showingMirror: Boolean

        get() = containerViewModel.brightnessSliderViewModel.showMirror



    // The initial values in these two are not meaningful. The flow will emit on start the correct

    // values. This is because we need to lazily fetch them after initMediaHosts.

    val qqsMediaVisible by

        hydrator.hydratedStateOf(

            traceName = "qqsMediaVisible",

            initialValue = usingMedia,

            source =

                if (usingMedia) {

                    mediaHostVisible(qqsMediaHost)

                } else {

                    flowOf(false)

                },

        )



    val qsMediaVisible by

        hydrator.hydratedStateOf(

            traceName = "qsMediaVisible",

            initialValue = usingMedia,

            source = if (usingMedia) mediaHostVisible(qsMediaHost) else flowOf(false),

        )



    private var qsBounds by mutableStateOf(Rect())



    private val constrainedSquishinessFraction: Float
@@ -259,9 +296,6 @@ constructor( 
                    .onStart { emit(sysuiStatusBarStateController.state) },

        )



    val showingMirror: Boolean

        get() = containerViewModel.brightnessSliderViewModel.showMirror



    private val isKeyguardState: Boolean

        get() = statusBarState == StatusBarState.KEYGUARD
@@ -323,6 +357,7 @@ constructor( 
        )



    override suspend fun onActivated(): Nothing {

        initMediaHosts() // init regardless of using media (same as current QS).

        coroutineScope {

            launch { hydrateSquishinessInteractor() }

            launch { hydrator.activate() }
@@ -331,6 +366,19 @@ constructor( 
        }

    }



    private fun initMediaHosts() {

        qqsMediaHost.apply {

            expansion = MediaHostState.EXPANDED

            showsOnlyActiveMedia = true

            init(MediaHierarchyManager.LOCATION_QQS)

        }

        qsMediaHost.apply {

            expansion = MediaHostState.EXPANDED

            showsOnlyActiveMedia = false

            init(MediaHierarchyManager.LOCATION_QS)

        }

    }



    private suspend fun hydrateSquishinessInteractor() {

        snapshotFlow { constrainedSquishinessFraction }

            .collect { squishinessInteractor.setSquishinessValue(it) }
@@ -373,6 +421,10 @@ constructor( 
                println("qqsHeight", "${qqsHeight}px")

                println("qsScrollHeight", "${qsScrollHeight}px")

            }

            printSection("Media") {

                println("qqsMediaVisible", qqsMediaVisible)

                println("qsMediaVisible", qsMediaVisible)

            }

        }

    }
@@ -390,3 +442,21 @@ private fun Float.constrainSquishiness(): Float { 
}



private val SHORT_PARALLAX_AMOUNT = 0.1f



/**

 * Returns a flow to track the visibility of a [MediaHost]. The flow will emit on start the visible

 * state of the view.

 */

private fun mediaHostVisible(mediaHost: MediaHost): Flow<Boolean> {

    return callbackFlow {

            val listener: (Boolean) -> Unit = { visible: Boolean -> trySend(visible) }

            mediaHost.addVisibilityChangeListener(listener)



            awaitClose { mediaHost.removeVisibilityChangeListener(listener) }

        }

        // Need to use this to set initial state because on creation of the media host, the

        // view visibility is not in sync with [MediaHost.visible], which is what we track with

        // the listener. The correct state is set as part of init, so we need to get the state

        // lazily.

        .onStart { emit(mediaHost.visible) }

}