[Wear] Scroll again to the next session in onResume

wearApp/src/main/java/fr/paug/androidmakers/wear/ui/common/SaveableLaunchedEffect.kt

@@ -0,0 +1,20 @@
+package fr.paug.androidmakers.wear.ui.common
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.saveable.rememberSaveable
+
+@Composable
+fun SaveableLaunchedEffect(
+  key: Any,
+  block: suspend () -> Unit
+) {
+  val lastLaunchedKey = rememberSaveable { mutableStateOf<Any?>(null) }
+  if (lastLaunchedKey.value != key) {
+    lastLaunchedKey.value = key
+    LaunchedEffect(Unit) {
+      block()
+    }
+  }
+}

wearApp/src/main/java/fr/paug/androidmakers/wear/ui/main/MainActivity.kt

@@ -17,6 +17,8 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.core.app.ActivityCompat
 import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.compose.LocalLifecycleOwner
 import androidx.navigation.NavType
 import androidx.navigation.navArgument
 import androidx.wear.compose.foundation.SwipeToDismissBoxState
@@ -39,6 +41,7 @@ import fr.paug.androidmakers.wear.ui.session.list.SessionListScreen
 import fr.paug.androidmakers.wear.ui.settings.SettingsScreen
 import fr.paug.androidmakers.wear.ui.signin.SignInScreen
 import fr.paug.androidmakers.wear.ui.theme.AndroidMakersWearTheme
+import kotlinx.coroutines.flow.map
 import org.koin.androidx.compose.koinViewModel
 import org.koin.core.parameter.parametersOf
 
@@ -86,6 +89,8 @@ fun WearApp(
 
   AndroidMakersWearTheme {
     AppScaffold {
+      val isResumed by LocalLifecycleOwner.current.lifecycle.currentStateFlow.map { it == Lifecycle.State.RESUMED }
+        .collectAsState(false)
       SwipeDismissableNavHost(
         navController = navController,
         startDestination = Navigation.main,
@@ -94,6 +99,7 @@ fun WearApp(
         composable(Navigation.main) {
           MainScreen(
             viewModel = viewModel,
+            isResumed = isResumed,
             swipeToDismissBoxState = swipeToDismissBoxState,
             onSignInClick = onSignInClick,
             onSignOutClick = { viewModel.signOut() },
@@ -125,6 +131,7 @@ fun WearApp(
 @Composable
 fun MainScreen(
   viewModel: MainViewModel,
+  isResumed: Boolean,
   swipeToDismissBoxState: SwipeToDismissBoxState,
   onSignInClick: () -> Unit,
   onSignOutClick: () -> Unit,
@@ -140,7 +147,8 @@ fun MainScreen(
     modifier = Modifier
       .fillMaxSize()
       .edgeSwipeToDismiss(swipeToDismissBoxState),
-    state = pagerState
+    state = pagerState,
+    beyondViewportPageCount = 2,
   ) { page ->
     when (page) {
       0 -> {
@@ -156,6 +164,7 @@ fun MainScreen(
         SessionListScreen(
           sessions = sessionsDay1,
           title = stringResource(id = R.string.main_day1),
+          isResumed = isResumed,
           onSessionClick = onSessionClick
         )
       }
@@ -164,6 +173,7 @@ fun MainScreen(
         SessionListScreen(
           sessions = sessionsDay2,
           title = stringResource(id = R.string.main_day2),
+          isResumed = isResumed,
           onSessionClick = onSessionClick
         )
       }

wearApp/src/main/java/fr/paug/androidmakers/wear/ui/session/list/SessionListScreen.kt

@@ -14,7 +14,6 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.rounded.Bookmark
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
-import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.alpha
@@ -45,6 +44,7 @@ import com.google.android.horologist.compose.material.ResponsiveListHeader
 import fr.paug.androidmakers.wear.R
 import fr.paug.androidmakers.wear.ui.common.Loading
 import fr.paug.androidmakers.wear.ui.common.PulsatingRedDot
+import fr.paug.androidmakers.wear.ui.common.SaveableLaunchedEffect
 import fr.paug.androidmakers.wear.ui.session.UISession
 import fr.paug.androidmakers.wear.ui.session.uiSessions
 import fr.paug.androidmakers.wear.ui.theme.amRed
@@ -53,6 +53,7 @@ import fr.paug.androidmakers.wear.ui.theme.amRed
 fun SessionListScreen(
   sessions: List<UISession>?,
   title: String,
+  isResumed: Boolean,
   onSessionClick: (String) -> Unit,
 ) {
   if (sessions == null) {
@@ -61,6 +62,7 @@ fun SessionListScreen(
     SessionList(
       sessions = sessions,
       title = title,
+      isResumed = isResumed,
       onSessionClick = onSessionClick,
     )
   }
@@ -70,6 +72,7 @@ fun SessionListScreen(
 private fun SessionList(
   sessions: List<UISession>,
   title: String,
+  isResumed: Boolean,
   onSessionClick: (String) -> Unit,
 ) {
   val columnState = rememberResponsiveColumnState(
@@ -79,13 +82,13 @@ private fun SessionList(
     )
   )
 
-  // Approximation of about half the height of a card, so the card is centered when scrolling to it.
-  // Maybe there's a way to get the actual height?
-  val scrollOffset = with(LocalDensity.current) { 80.dp.roundToPx() }
-
-  val nextSessionIndex = sessions.nextSessionIndex()
-  if (nextSessionIndex > 0) {
-    LaunchedEffect(Unit) {
+  val density = LocalDensity.current
+  SaveableLaunchedEffect(isResumed) {
+    val nextSessionIndex = sessions.nextSessionIndex()
+    if (nextSessionIndex > 0) {
+      // Approximation of about half the height of a card, so the card is centered when scrolling to it.
+      // Maybe there's a way to get the actual height?
+      val scrollOffset = with(density) { 80.dp.roundToPx() }
       columnState.state.scrollToItem(
         // Add 1 to the index to account for the title
         index = nextSessionIndex + 1,
@@ -220,12 +223,12 @@ private fun SessionItem(
 @WearPreviewFontScales
 @Composable
 private fun LoadingSessionListScreenPreview() {
-  SessionListScreen(null, stringResource(id = R.string.main_day1), {})
+  SessionListScreen(null, stringResource(id = R.string.main_day1), true, {})
 }
 
 @WearPreviewDevices
 @WearPreviewFontScales
 @Composable
 private fun LoadedSessionListScreenPreview() {
-  SessionListScreen(uiSessions, stringResource(id = R.string.main_day1), {})
+  SessionListScreen(uiSessions, stringResource(id = R.string.main_day1), true, {})
 }