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ui: Fix recompose loop during scroll (2fps vertical)

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Focus requesters were stored in snapshot-state maps and written during
composition of every list item: each write invalidated the reading
scope, which recomposed the (whole page of) items, wrote again, ...
This feedback loop is why vertical scrolling ran at ~2fps on the TV
while the same build scrolled fine in the emulator's short bursts.
Plain HashMaps kill the loop - focus handling needs no recomposition.
This commit is contained in:
Jeena 2026-10-11 05:17:12 +00:00
parent f7273121ae
commit 5ea1ca5124
2 changed files with 2 additions and 2 deletions
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2
app/src/main/java/net/jeena/jtubetv/ui/screens/ChannelsScreen.kt
View file

@ -237,7 +237,7 @@ private fun ChannelCardRow(
onLeftAtStart: () -> Unit, onLeftAtStart: () -> Unit,
) { ) {
val rowState = androidx.compose.foundation.lazy.rememberLazyListState() val rowState = androidx.compose.foundation.lazy.rememberLazyListState()
val focusRequesters = remember { mutableMapOf<Int, FocusRequester>() } val focusRequesters = remember { HashMap<Int, FocusRequester>() }
var focusedIndex by remember { mutableIntStateOf(-1) } var focusedIndex by remember { mutableIntStateOf(-1) }
var clickedIndex by remember { mutableIntStateOf(-1) } var clickedIndex by remember { mutableIntStateOf(-1) }

2
app/src/main/java/net/jeena/jtubetv/ui/screens/HomeRows.kt
View file

@ -260,7 +260,7 @@ fun FocusScrollRow(
afterItem: @Composable (index: Int, video: VideoDto) -> Unit = { _, _ -> }, afterItem: @Composable (index: Int, video: VideoDto) -> Unit = { _, _ -> },
) { ) {
val rowState = rememberLazyListState() val rowState = rememberLazyListState()
val focusRequesters = remember { androidx.compose.runtime.mutableStateMapOf<Int, FocusRequester>() } val focusRequesters = remember { HashMap<Int, FocusRequester>() }
var focusedIndex by remember { androidx.compose.runtime.mutableStateOf(-1) } var focusedIndex by remember { androidx.compose.runtime.mutableStateOf(-1) }
// BACK from playback: scroll to + focus the card that was opened (user request). // BACK from playback: scroll to + focus the card that was opened (user request).
LaunchedEffect(restoreToken) { LaunchedEffect(restoreToken) {