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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.
npx skill4agent add android/skills leanback-to-compose-tv-migrationUpDownLeftRightandroidx.tvandroidx.tv.material3.*androidx.tv:tv-materialandroidx.compose.material3.*CompactCardClassicCardWideCardContainerscale = CardDefaults.scale(focusedScale = 1.1f)AsyncImage(model, contentDescription, ...)ImageLoaderio.coil-kt:coil-composeimport androidx.tv.material3.Surfaceimport androidx.tv.material3.ListItemimport androidx.tv.material3.*BrowseScreenBrowseScreen.ktPlaybackScreenPlaybackScreen.ktAuthenticationScreenAuthenticationScreen.ktMainhorizontal = 48.dp32.dpvertical = 24.dpModifier.widthIn(max = 600.dp)androidx.media3:media3-ui-composeapp/build.gradleAndroidViewPlayerSurfaceandroidx.tv.material3ListItemFocusRequesterval focusRequester = remember { FocusRequester() }Modifier.focusRequester(focusRequester)LaunchedEffect(Unit) { focusRequester.requestFocus() }val focusRequester = remember { FocusRequester() }
val focusManager = LocalFocusManager.current
LaunchedEffect(Unit) {
focusRequester.requestFocus()
}
OnboardingScreenHorizontalPagerLaunchedEffectLaunchedEffect(pagerState.currentPage)LazyColumnLazyRowup = ...down = ...FocusRequesterIllegalStateExceptionRow(
modifier = Modifier
.fillMaxWidth()
.padding(horizontal = 48.dp, vertical = 16.dp),
horizontalArrangement = Arrangement.End
) {
Button(
onClick = { /* Search */ },
modifier = Modifier.focusRequester(topBarFocusRequester)
) { Text("Search") }
}
Modifier.focusRestorerLazyRowModifier.focusRestorerLazyRowFocusRequesterrequestFocusIllegalStateExceptionLazyRow(
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
}
}
)
}
}
SearchSupportFragmentGuidedStepSupportFragmentBasicTextFieldSurface(onClick = {})onPreviewKeyEventTextFieldSurface(onClick = { focusRequester.requestFocus() }, scale = ClickableSurfaceDefaults.scale(focusedScale = 1.01f), border = ClickableSurfaceDefaults.border(focusedBorder = Border(BorderStroke(2.dp, Color.White))))Modifier.onPreviewKeyEventKey.BackKey.EscapeKey.BackKey.EscapeKeyUponPreviewKeyEventKeyboardActions(onNext = { focusManager.moveFocus(FocusDirection.Down) })ImeAction.NextImeAction.DoneSurface(
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
}
)
}
LazyColumnLazyRowLazyVerticalGridandroidx.compose.foundation.lazyandroidx.compose.foundation.lazy.gridBringIntoViewSpecBringIntoViewSpecCompositionLocalProvider(LocalBringIntoViewSpec provides ...)implementation platform('androidx.compose:compose-bom:2024.06.00')implementation 'androidx.compose.foundation:foundation:1.7.0'app/build.gradleimport androidx.compose.foundation.gestures.LocalBringIntoViewSpecUnresolved reference: LocalBringIntoViewSpecModifier.focusRestorer@OptIn(ExperimentalFocusRestorerApi::class, ExperimentalComposeUiApi::class)Modifier.focusRestorerLazyRowCompactCardListItemButton@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)
}
}
}
VideoSupportFragmentPlaybackGluePlayerSurfaceandroidx.media3.ui.compose.PlayerSurfacePlayPauseButtonPlayerSurfaceBox(modifier = Modifier.align(Alignment.BottomCenter))PlayPauseButtonSeekBackButtonSeekForwardButtonimplementation 'androidx.media3:media3-ui-compose-material3:1.6.0'androidx.media3:media3-ui-composeapp/build.gradleonPreviewKeyEventModifier.onPreviewKeyEventKey.DirectionLeftKey.DirectionRightkeyEvent.key == Key.DirectionLeftexoPlayer.seekTo(exoPlayer.currentPosition - 10000)KeyEvent.KEYCODE_DPAD_LEFTnativeKeyEvent.keyCodePlayerViewStyledPlayerViewAndroidView { ... }PlayerSurfaceandroidx.media3.ui.compose.PlayerSurfaceExoPlayerTvTheme.ktTvMaterialThemeColorSchemeTypographyShapesMovieCardSectionHeaderLoadingIndicatorErrorStateErrorDialogOnboardingScreenSettingsScreenBaseLeanbackPreferenceFragmentCompatBaseLeanbackPreferenceFragmentLeanbackSettingsFragmentListItemSwitchSharedPreferencesfindPreferenceFocusRequesterListItemFragmentComponentActivityres/values/styles.xmlres/values/themes.xmlpreferenceTheme@style/PreferenceThemeOverlay.v14.Leanback@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
)
}
)
}
}
}
}
VerticalGridScreenLazyVerticalGridSearchScreenBasicTextFieldBrowseScreenLazyColumnLazyRowArrayObjectAdapterListRowPresenterCardPresenterHeaderItemVideoDetailsScreenGuidedStepScreenPlaybackScreenPlayerSurfaceandroidx.media3.ui.compose.PlayerSurfacePlayPauseButtonSeekBackButtonSeekForwardButton.javaComponentActivityFragmentActivitysetContent { ... }res/values/styles.xmlres/values/themes.xmlTheme.Leanbacklb_| Legacy Leanback / View Class | Modern Jetpack Compose Equivalent |
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| Declarative |
| Kotlin Coroutines / |
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BrowseScreenBringIntoViewanimateScrollToItemBringIntoViewSpecLocalBringIntoViewSpecfocusedCategoryIndex > 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)
}
PlaybackScreenandroidx.media3.ui.compose.PlayerSurfaceSeekBackButtonPlayPauseButtonSeekForwardButtonandroidx.media3:media3-ui-compose-material3@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)
}
}
}
}
}
LoaderManager.LoaderCallbacks<Cursor>CursorObjectAdapterFlowobject 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()
}
}