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leanback-to-compose-tv-migration【开发与工程】Provides instructions and architectural patterns for migrating Android TV applications from legacy Leanback UI Toolkit, Android Views, or Support Fragments to Jetpack Compose for TV (androidx.tv). Use this skill for Leanback to Compose migrations, including browse screen, settings screen, authentication screen, login screen, or video playback screen …
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name: leanback-to-compose-tv-migration description: Provides instructions and architectural patterns for migrating Android TV applications from legacy Leanback UI Toolkit, Android Views, or Support Fragments to Jetpack Compose for TV (androidx.tv). Use this skill for Leanback to Compose migrations, including browse screen, settings screen, authentication screen, login screen, or video playback screen migrations, or when replacing BrowseSupportFragment, LeanbackSettingsFragment, PreferenceFragment, BaseLeanbackPreferenceFragmentCompat, VideoSupportFragment, GuidedStepSupportFragment, SearchSupportFragment, VerticalGridSupportFragment, Presenter, ArrayObjectAdapter, or CursorMapper with modern Compose equivalents, implementing immersive carousels with focus memory, Media3 video playback with PlayerSurface, or custom 10-foot hero layouts. license: Complete terms in LICENSE.txt metadata: author: Google LLC last-updated: '2026-09-18' keywords:
A "10-foot UI" is a design paradigm for televisions that tailors an interface for viewing from approximately 3 meters (10 feet) away. When designing for this experience, account for these key characteristics:
Up, Down, Left, Right) with components organized into clear spatial grids and carousels without focus traps.When migrating an Android TV application to Jetpack Compose, you must use
androidx.tv libraries and follow these 10-foot UI patterns:
androidx.tv.material3.* (androidx.tv:tv-material) over mobile androidx.compose.material3.*. TV Material 3 provides built-in D-Pad focus handling, focus zoom scaling, and TV-optimized typography and shapes. To set up Compose for TV dependencies, follow Compose for TV setup.CompactCard, ClassicCard, or WideCardContainer with scale = CardDefaults.scale(focusedScale = 1.1f) to provide standard TV focus animation.AsyncImage(model, contentDescription, ...) without passing an explicit ImageLoader parameter, you must include io.coil-kt:coil-compose in your Gradle dependencies.import androidx.tv.material3.Surface, import androidx.tv.material3.ListItem) instead of using wildcard imports (import androidx.tv.material3.*).BrowseScreen as BrowseScreen.kt, PlaybackScreen as PlaybackScreen.kt, and AuthenticationScreen as AuthenticationScreen.kt). Don't use generic prefixes like Main.horizontal = 48.dp or 32.dp, vertical = 24.dp) to root containers, carousels, and top bars to prevent clipping.Modifier.widthIn(max = 600.dp) on text columns for long-form text.androidx.media3:media3-ui-compose in app/build.gradle when modernizing media playback screens.AndroidView wrappers to embed View-based components into Jetpack Compose screens. All migrated screens must use Compose components or Media3 Compose surfaces (PlayerSurface).Jetpack Compose for TV (androidx.tv.material3) requires explicit focus
management, as components don't receive initial focus automatically and
navigation uses 2D spatial coordinates. To configure TV D-pad navigation, follow
instructions in TV Navigation guide.
You must assign initial focus to the primary interactive element on every screen
(such as the first action button, card, or ListItem) using FocusRequester
when entering a screen. Define val focusRequester = remember { FocusRequester() }, attach Modifier.focusRequester(focusRequester) to the primary element, and
request focus inside LaunchedEffect(Unit) { focusRequester.requestFocus() }:
val focusRequester = remember { FocusRequester() }
val focusManager = LocalFocusManager.current
LaunchedEffect(Unit) {
focusRequester.requestFocus()
}
Note: For screens with dynamic state or pagers (like OnboardingScreen using
HorizontalPager), you must pass the state key to LaunchedEffect (for example
LaunchedEffect(pagerState.currentPage)) so that focus is re-applied when the
page changes.
When interactive elements sit on opposite sides of the display, standard 2D spatial navigation fails to find targets across them. This creates focus traps where users are unable to navigate out of an area using the D-pad.
For symmetrical, bidirectional D-pad navigation without focus traps, you must
rely on Compose's 2D spatial focus engine whenever possible. When connecting
adjacent UI elements across scrollable containers (like LazyColumn or
LazyRow), don't set directional overrides (up = ..., down = ...) targeting
individual items inside lazy lists. When an item scrolls off-screen during
vertical navigation, its FocusRequester becomes uninitialized, throwing
IllegalStateException during focus searches:
Row(
modifier = Modifier
.fillMaxWidth()
.padding(horizontal = 48.dp, vertical = 16.dp),
horizontalArrangement = Arrangement.End
) {
Button(
onClick = { /* Search */ },
modifier = Modifier.focusRequester(topBarFocusRequester)
) { Text("Search") }
}
Modifier.focusRestorer)When navigating vertically between horizontal carousels (LazyRow), Compose's
default 2D spatial focus engine searches along the X coordinate of the focused
item. If a user scrolls right in Row 1 (for example to Item 4 at X=800dp) and
presses DOWN to navigate to Row 2, spatial routing focuses whatever item sits at
X=800dp in Row 2.
To make every row maintain its own recollection of card focus (restoring focus
to the previously visited item when revisited), you must attach
Modifier.focusRestorer (with no arguments) directly to the LazyRow.
Don't pass custom fallback FocusRequester lambdas in lazy containers, as
calling requestFocus on an unattached or off-screen item during rapid D-pad
scrolling throws IllegalStateException.
LazyRow(
modifier = Modifier.focusRestorer(),
contentPadding = PaddingValues(horizontal = 48.dp),
horizontalArrangement = Arrangement.spacedBy(16.dp)
) {
itemsIndexed(videos) { vidIndex, video ->
CompactCard(
onClick = { onVideoClick(video) },
image = {
AsyncImage(
model = video.cardImageUrl,
contentDescription = video.title,
contentScale = ContentScale.Crop,
modifier = Modifier.fillMaxSize()
)
},
title = { Text(video.title) },
modifier = Modifier
.then(
if (catIndex == 0 && vidIndex == 0) {
Modifier.focusRequester(firstCardFocusRequester)
} else {
Modifier
}
)
.onFocusChanged { focusState ->
if (focusState.isFocused) {
focusedVideo = video
focusedCategoryIndex = catIndex
}
}
)
}
}
When migrating search bars or login forms from Leanback
(SearchSupportFragment, GuidedStepSupportFragment), don't use bare
BasicTextField containers or empty Surface(onClick = {}) wrappers, as they
prevent D-pad CENTER from attaching the virtual keyboard (IME).
onPreviewKeyEvent) : Wrap standard M3 TextField inside a focusable TV Surface(onClick = { focusRequester.requestFocus() }, scale = ClickableSurfaceDefaults.scale(focusedScale = 1.01f), border = ClickableSurfaceDefaults.border(focusedBorder = Border(BorderStroke(2.dp, Color.White)))) to provide a focused border outline and D-pad focus scaling. You must attach Modifier.onPreviewKeyEvent on the text field or wrapper to intercept Key.Back and Key.Escape so the user's able to remove focus from the input field without exiting the screen.Key.Back and Key.Escape on KeyUp in onPreviewKeyEvent to stop editing (clearing focus), the user's able to return to D-pad form navigation without being trapped in the text field or accidentally exiting the screen.KeyboardActions(onNext = { focusManager.moveFocus(FocusDirection.Down) }) with ImeAction.Next on top fields to route focus down to the next input box, and ImeAction.Done on the bottom field to route focus directly to the submit button:Surface(
onClick = { focusRequester.requestFocus() },
border = ClickableSurfaceDefaults.border(focusedBorder = Border(border = BorderStroke(2.dp, Color.White))),
modifier = Modifier
.fillMaxWidth()
.focusRequester(focusRequester)
) {
OutlinedTextField(
value = username,
onValueChange = { username = it },
label = { Text("Username") },
singleLine = true,
keyboardOptions = KeyboardOptions(imeAction = ImeAction.Next),
keyboardActions = KeyboardActions(onNext = { focusManager.moveFocus(FocusDirection.Down) }),
modifier = Modifier
.fillMaxWidth()
.onPreviewKeyEvent { event ->
if (event.type == KeyEventType.KeyDown && (event.key == Key.Enter || event.key == Key.NumPadEnter)) {
focusManager.moveFocus(FocusDirection.Down)
true
} else false
}
)
}
Surface(
onClick = {},
border = ClickableSurfaceDefaults.border(focusedBorder = Border(border = BorderStroke(2.dp, Color.White))),
modifier = Modifier.fillMaxWidth()
) {
OutlinedTextField(
value = password,
onValueChange = { password = it },
label = { Text("Password") },
singleLine = true,
visualTransformation = PasswordVisualTransformation(),
keyboardOptions = KeyboardOptions(imeAction = ImeAction.Done),
keyboardActions = KeyboardActions(onDone = { onLoginSuccess() }),
modifier = Modifier
.fillMaxWidth()
.onPreviewKeyEvent { event ->
if (event.type == KeyEventType.KeyDown && (event.key == Key.Enter || event.key == Key.NumPadEnter)) {
onLoginSuccess()
true
} else false
}
)
}
When implementing scrollable lists or grids in Jetpack Compose for TV, you must
use standard LazyColumn, LazyRow, and LazyVerticalGrid from
androidx.compose.foundation.lazy and androidx.compose.foundation.lazy.grid.
For catalog browsing layouts, follow instructions in Catalog Browser guide.
BringIntoViewSpec : When defining a custom pivot scroll line for catalog rows using BringIntoViewSpec and CompositionLocalProvider(LocalBringIntoViewSpec provides ...), you must ensure your project compiles against Compose Foundation 1.7.0+ by adding implementation platform('androidx.compose:compose-bom:2024.06.00') (or newer) or implementation 'androidx.compose.foundation:foundation:1.7.0' in app/build.gradle. Without Compose Foundation 1.7.0+, import androidx.compose.foundation.gestures.LocalBringIntoViewSpec will fail with Unresolved reference: LocalBringIntoViewSpec.Modifier.focusRestorer) : Annotate your composable with @OptIn(ExperimentalFocusRestorerApi::class, ExperimentalComposeUiApi::class) and attach Modifier.focusRestorer on every category LazyRow to remember and restore the last focused card when navigating vertically across catalog rows.When populated with focusable TV Material 3 components (CompactCard,
ListItem, Button), standard Compose lazy containers handle 2D D-Pad focus
routing, focus memory, and edge scrolling automatically:
@Composable
fun CatalogBrowser(
featuredContentList: List<Movie>,
sectionList: List<Section>,
modifier: Modifier = Modifier,
onItemSelected: (Movie) -> Unit = {},
) {
LazyColumn(
modifier = modifier.fillMaxSize(),
verticalArrangement = Arrangement.spacedBy(16.dp)
) {
items(sectionList.size) { index ->
val section = sectionList[index]
SectionRow(section, onItemSelected = onItemSelected)
}
}
}
When migrating legacy Leanback video playback (VideoSupportFragment /
PlaybackGlue), use Compose Media3 PlayerSurface
(androidx.media3.ui.compose.PlayerSurface) combined with a translucent
transport controls overlay:
PlayPauseButton) : Over the PlayerSurface, you must layer a translucent bottom controls bar (Box(modifier = Modifier.align(Alignment.BottomCenter))) containing explicit Media3 UI Compose buttons: at minimum PlayPauseButton, SeekBackButton, and SeekForwardButton. Never leave the transport controls overlay empty. To use these composables, you must add implementation 'androidx.media3:media3-ui-compose-material3:1.6.0' alongside androidx.media3:media3-ui-compose in your app/build.gradle dependencies.onPreviewKeyEvent) : To support seeking backward and forward with the remote control D-pad, attach Modifier.onPreviewKeyEvent on the container or controls overlay and intercept Compose Key.DirectionLeft and Key.DirectionRight (for example, keyEvent.key == Key.DirectionLeft) to seek backward and forward by 10 seconds (exoPlayer.seekTo(exoPlayer.currentPosition - 10000)). Never use legacy Android View keycodes (KeyEvent.KEYCODE_DPAD_LEFT or nativeKeyEvent.keyCode).PlayerView or StyledPlayerView in AndroidView { ... }. You must use PlayerSurface (androidx.media3.ui.compose.PlayerSurface) with ExoPlayer for video rendering in Compose for TV.To migrate an app cleanly without breaking compilation or introducing circular dependencies, execute in five distinct phases:
TvTheme.kt wrapping TvMaterialTheme with custom ColorScheme, Typography, and Shapes.MovieCard, SectionHeader, LoadingIndicator, ErrorState.ErrorDialog, OnboardingScreen, and SettingsScreen.BaseLeanbackPreferenceFragmentCompat, BaseLeanbackPreferenceFragment, or LeanbackSettingsFragment to use Compose, for example by using ListItem + Switch bound directly to SharedPreferences and replacing the findPreference implementation.FocusRequester, for example on the first ListItem.Fragment classes with activities of type ComponentActivity that declaratively use components in Compose.res/values/styles.xml and res/values/themes.xml (such as removing preferenceTheme that points to @style/PreferenceThemeOverlay.v14.Leanback) that aren't supported once leanback dependencies are removed:@Composable
fun TvSettingsScreen(
modifier: Modifier = Modifier
) {
var autoPlayNext by remember { mutableStateOf(true) }
var highQualityAudio by remember { mutableStateOf(false) }
Column(
modifier = modifier
.fillMaxSize()
.padding(48.dp)
) {
Text(
text = "Settings",
style = MaterialTheme.typography.headlineMedium,
modifier = Modifier.padding(bottom = 24.dp)
)
LazyColumn(
verticalArrangement = Arrangement.spacedBy(12.dp),
contentPadding = PaddingValues(vertical = 8.dp)
) {
item {
ListItem(
selected = false,
onClick = { autoPlayNext = !autoPlayNext },
headlineContent = { Text("Autoplay Next Video") },
supportingContent = { Text("Automatically start playing next item in queue") },
trailingContent = {
Switch(
checked = autoPlayNext,
onCheckedChange = null
)
}
)
}
item {
ListItem(
selected = false,
onClick = { highQualityAudio = !highQualityAudio },
headlineContent = { Text("High Quality Audio") },
supportingContent = { Text("Use spatial audio and multi-channel output when available") },
trailingContent = {
Switch(
checked = highQualityAudio,
onCheckedChange = null
)
}
)
}
}
}
}
VerticalGridScreen (LazyVerticalGrid), SearchScreen (BasicTextField with live list filtering), and BrowseScreen (LazyColumn of LazyRows).ArrayObjectAdapter, ListRowPresenter, CardPresenter, and HeaderItem classes.VideoDetailsScreen and GuidedStepScreen.PlaybackScreen using Compose Media3 PlayerSurface (androidx.media3.ui.compose.PlayerSurface) paired with a translucent bottom overlay containing Media3 Compose transport controls (such as PlayPauseButton, SeekBackButton, SeekForwardButton)..java activities, fragments, presenters, and XML layout files.ComponentActivity or FragmentActivity calling setContent { ... }.res/values/styles.xml and res/values/themes.xml (for example, any styles inheriting from Theme.Leanback or referencing lb_ styles).| Legacy Leanback / View Class | Modern Jetpack Compose Equivalent |
|---|---|
BrowseSupportFragment / MainFragment | BrowseScreen (LazyColumn containing categorized LazyRows + Hero Banner) |
DetailsSupportFragment | VideoDetailsScreen (Poster image, text column, action buttons, related LazyRow) |
VideoSupportFragment / PlaybackGlue | PlaybackScreen (Media3 ExoPlayer + Compose PlayerSurface) |
GuidedStepSupportFragment | GuidedStepScreen (Split-screen layout: 40% left guidance pane, 60% right actions pane) |
SearchSupportFragment | SearchScreen (BasicTextField + live filtering + LazyVerticalGrid) |
VerticalGridSupportFragment | VerticalGridScreen (LazyVerticalGrid(columns = GridCells.Fixed(5))) |
ArrayObjectAdapter / Presenter | Declarative @Composable functions observing immutable State<List<T>> |
CursorMapper / LoaderManager / CursorLoader | Kotlin Coroutines / withContext(Dispatchers.IO) in a Repository object |
OnboardingSupportFragment | OnboardingScreen (HorizontalPager + D-Pad navigation buttons) |
LeanbackSettingsFragment / PreferenceFragment | SettingsScreen (FocusRequester on first ListItem + trailing Switch bound to SharedPreferences) |
BrowseScreen)When building a 10-foot TV browse screen or Immersive List, don't place a hero
banner before or outside a scrolling list, and don't fight Compose's automatic
BringIntoView system with programmatic animateScrollToItem calls.
Instead, use BringIntoViewSpec with LocalBringIntoViewSpec from Compose
Foundation to define exact TV pivot scrolling (for example, pivoting active rows
at 35% from the top edge of the display). Combine this with a reshaping
immersive row: when lower rows are focused (focusedCategoryIndex > 0), hide
the hero text and display a normal section header on Row 0:
@Composable
fun ImmersiveBrowseScreen(
categories: Map<String, List<Video>>,
onVideoClick: (Video) -> Unit
) {
var focusedVideo by remember { mutableStateOf<Video?>(null) }
var focusedCategoryIndex by remember { mutableStateOf(0) }
val listState = rememberLazyListState()
val topBarFocusRequester = remember { FocusRequester() }
val firstCardFocusRequester = remember { FocusRequester() }
Box(modifier = Modifier.fillMaxSize()) {
AsyncImage(
model = focusedVideo?.bgImageUrl,
contentDescription = null,
contentScale = ContentScale.Crop,
modifier = Modifier.fillMaxSize()
)
PositionFocusedItemInLazyLayout(parentFraction = 0.35f, childFraction = 0.5f) {
LazyColumn(
state = listState,
contentPadding = PaddingValues(top = 36.dp, bottom = 64.dp),
verticalArrangement = Arrangement.spacedBy(28.dp),
modifier = Modifier.fillMaxSize()
) {
item {
Row(
modifier = Modifier
.fillMaxWidth()
.padding(horizontal = 48.dp, vertical = 16.dp),
horizontalArrangement = Arrangement.End
) {
Button(
onClick = { /* Search */ },
modifier = Modifier.focusRequester(topBarFocusRequester)
) { Text("Search") }
}
}
itemsIndexed(categories.entries.toList()) { catIndex, (categoryName, videos) ->
Column {
if (catIndex == 0 && focusedCategoryIndex == 0) {
Column(
modifier = Modifier
.heightIn(min = 200.dp)
.padding(horizontal = 48.dp)
) {
Text(
text = focusedVideo?.title ?: "",
style = MaterialTheme.typography.displayMedium
)
Text(
text = focusedVideo?.description ?: "",
style = MaterialTheme.typography.bodyLarge
)
}
} else {
Text(
text = categoryName,
style = MaterialTheme.typography.titleMedium,
modifier = Modifier.padding(horizontal = 48.dp, vertical = 8.dp)
)
}
LazyRow(
modifier = Modifier.focusRestorer(),
contentPadding = PaddingValues(horizontal = 48.dp),
horizontalArrangement = Arrangement.spacedBy(16.dp)
) {
itemsIndexed(videos) { vidIndex, video ->
CompactCard(
onClick = { onVideoClick(video) },
image = {
AsyncImage(
model = video.cardImageUrl,
contentDescription = video.title,
contentScale = ContentScale.Crop,
modifier = Modifier.fillMaxSize()
)
},
title = { Text(video.title) },
modifier = Modifier
.then(
if (catIndex == 0 && vidIndex == 0) {
Modifier.focusRequester(firstCardFocusRequester)
} else {
Modifier
}
)
.onFocusChanged { focusState ->
if (focusState.isFocused) {
focusedVideo = video
focusedCategoryIndex = catIndex
}
}
)
}
}
}
}
}
}
}
}
@OptIn(ExperimentalFoundationApi::class)
@Composable
private fun PositionFocusedItemInLazyLayout(
parentFraction: Float = 0.35f,
childFraction: Float = 0.5f,
content: @Composable () -> Unit,
) {
val bringIntoViewSpec = remember(parentFraction, childFraction) {
object : BringIntoViewSpec {
override fun calculateScrollDistance(
offset: Float,
size: Float,
containerSize: Float
): Float {
if (offset >= 0f && offset <= containerSize * 0.45f) {
return 0f
}
val initialTargetForLeadingEdge = parentFraction * containerSize - (childFraction * size)
val targetForLeadingEdge = if (size <= containerSize && (containerSize - initialTargetForLeadingEdge) < size) {
containerSize - size
} else {
initialTargetForLeadingEdge
}
return offset - targetForLeadingEdge
}
}
}
CompositionLocalProvider(LocalBringIntoViewSpec provides bringIntoViewSpec, content = content)
}
PlaybackScreen)Implement a custom playback screen using
androidx.media3.ui.compose.PlayerSurface as the video rendering canvas. Layer
Material3 transport controls (SeekBackButton, PlayPauseButton,
SeekForwardButton from androidx.media3:media3-ui-compose-material3) over the
surface in a translucent bottom overlay, and handle D-pad remote key events with
an auto-hide timeout:
@OptIn(UnstableApi::class)
@Composable
fun Media3PlaybackScreen(
video: Video,
onFinish: () -> Unit,
modifier: Modifier = Modifier
) {
val context = LocalContext.current
val exoPlayer = remember(context) { ExoPlayer.Builder(context).build() }
var showControls by remember { mutableStateOf(true) }
val focusRequester = remember { FocusRequester() }
val coroutineScope = rememberCoroutineScope()
var autoHideJob by remember { mutableStateOf<Job?>(null) }
fun scheduleAutoHide() {
autoHideJob?.cancel()
autoHideJob = coroutineScope.launch {
delay(5000)
showControls = false
}
}
DisposableEffect(exoPlayer) {
val listener = object : Player.Listener {
override fun onPlaybackStateChanged(playbackState: Int) {
if (playbackState == Player.STATE_ENDED) {
onFinish()
}
}
}
exoPlayer.addListener(listener)
onDispose {
autoHideJob?.cancel()
exoPlayer.removeListener(listener)
exoPlayer.release()
}
}
LaunchedEffect(video) {
focusRequester.requestFocus()
scheduleAutoHide()
val mediaItem = MediaItem.fromUri(video.videoUrl)
exoPlayer.setMediaItem(mediaItem)
exoPlayer.prepare()
exoPlayer.playWhenReady = true
}
Box(
modifier = modifier
.fillMaxSize()
.background(Color.Black)
.focusRequester(focusRequester)
.focusable()
.onPreviewKeyEvent { event ->
if (event.type == KeyEventType.KeyDown) {
when (event.key) {
Key.DirectionCenter, Key.Enter, Key.NumPadEnter, Key.MediaPlayPause, Key.Spacebar -> {
if (exoPlayer.isPlaying) exoPlayer.pause() else exoPlayer.play()
showControls = true
scheduleAutoHide()
true
}
Key.DirectionLeft, Key.MediaRewind -> {
val newPos = (exoPlayer.currentPosition - 10_000L).coerceAtLeast(0L)
exoPlayer.seekTo(newPos)
showControls = true
scheduleAutoHide()
true
}
Key.DirectionRight, Key.MediaFastForward -> {
val duration = exoPlayer.duration.coerceAtLeast(0L)
val newPos = (exoPlayer.currentPosition + 10_000L).coerceAtMost(duration)
exoPlayer.seekTo(newPos)
showControls = true
scheduleAutoHide()
true
}
Key.DirectionUp, Key.DirectionDown -> {
showControls = !showControls
if (showControls) scheduleAutoHide() else autoHideJob?.cancel()
true
}
else -> false
}
} else false
},
contentAlignment = Alignment.Center
) {
PlayerSurface(
player = exoPlayer,
modifier = Modifier.fillMaxSize()
)
if (showControls) {
Box(
modifier = Modifier
.fillMaxSize()
.background(Color(0x80000000))
.padding(48.dp),
contentAlignment = Alignment.BottomCenter
) {
Row(
horizontalArrangement = Arrangement.spacedBy(24.dp),
verticalAlignment = Alignment.CenterVertically
) {
SeekBackButton(player = exoPlayer)
PlayPauseButton(player = exoPlayer)
SeekForwardButton(player = exoPlayer)
}
}
}
}
}
Replace legacy LoaderManager.LoaderCallbacks<Cursor> and CursorObjectAdapter
with a repository returning a Flow that observes database changes and triggers
asynchronous fetching when empty:
object VideoFlowRepository {
fun getVideosFlow(context: Context, contentUri: Uri): Flow<List<Video>> = callbackFlow {
val contentObserver = object : ContentObserver(Handler(Looper.getMainLooper())) {
override fun onChange(selfChange: Boolean) {
trySend(queryVideos(context, contentUri))
}
}
context.contentResolver.registerContentObserver(
contentUri,
true,
contentObserver
)
val initialVideos = queryVideos(context, contentUri)
trySend(initialVideos)
awaitClose {
context.contentResolver.unregisterContentObserver(contentObserver)
}
}.flowOn(Dispatchers.IO)
private fun queryVideos(context: Context, uri: Uri): List<Video> {
// Query database or ContentProvider
return emptyList()
}
}