Release v2.22.5 (#381)

When you reopened the app the next morning, the month view still marked yesterday as today and still had the day you picked the evening before selected.

- New `TodaySource` gives the current date. It rechecks once a minute while a calendar is visible, and also reacts to the system's date, time and time-zone broadcasts. Month, Week/Day/3-day, Agenda and the shared date that every view opens on all use it.
- On a day change, a view still showing the old today moves to the new one, and Split clears the previous day's selection. A view you navigated elsewhere stays where it is.
- Month and Week take today from the live value instead of their cached page data.
- The issue only mentions the month view. The same stale today also affected Week, Day, Agenda and switching between views, so all of them are fixed.
- versionName 2.22.5 / versionCode 2220599, CHANGELOG, What's New in all 17 locales.

Closes #373

Co-authored-by: Jean-Luc Makiola <business@jeanlucmakiola.de>
Reviewed-on: https://codeberg.org/jlmakiola/calendula/pulls/381

app/src/main/java/de/jeanlucmakiola/calendula/data/di/DataModule.kt

@@ -20,6 +20,8 @@ import de.jeanlucmakiola.calendula.data.contacts.ContactSpecialDatesDataSource
 import de.jeanlucmakiola.calendula.data.contacts.SpecialDatesCalendarSpec
 import de.jeanlucmakiola.calendula.data.reminders.ProviderReminderInstanceSource
 import de.jeanlucmakiola.calendula.data.reminders.ReminderInstanceSource
+import de.jeanlucmakiola.calendula.data.time.AndroidTodaySource
+import de.jeanlucmakiola.calendula.data.time.TodaySource
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.Dispatchers
 import javax.inject.Singleton
@@ -61,6 +63,12 @@ abstract class DataBindModule {
     abstract fun bindSpecialDatesCalendarSpec(
         impl: AndroidSpecialDatesCalendarSpec,
     ): SpecialDatesCalendarSpec
+
+    @Binds
+    @Singleton
+    abstract fun bindTodaySource(
+        impl: AndroidTodaySource,
+    ): TodaySource
 }
 
 @Module

app/src/main/java/de/jeanlucmakiola/calendula/data/time/TodaySource.kt

@@ -0,0 +1,63 @@
+package de.jeanlucmakiola.calendula.data.time
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import androidx.core.content.ContextCompat
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.callbackFlow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.onStart
+import kotlinx.coroutines.flow.transformLatest
+import kotlinx.datetime.LocalDate
+import kotlinx.datetime.TimeZone
+import kotlinx.datetime.toLocalDateTime
+import javax.inject.Inject
+import kotlin.time.Clock
+
+/** The current local date, re-emitted whenever it changes (#373). */
+interface TodaySource {
+    val today: Flow<LocalDate>
+}
+
+/**
+ * Re-reads the date on every minute boundary while collected, and at once on the
+ * system's date, time and zone broadcasts, which can arrive late or not at all.
+ */
+@OptIn(ExperimentalCoroutinesApi::class)
+class AndroidTodaySource @Inject constructor(
+    @ApplicationContext private val context: Context,
+) : TodaySource {
+
+    override val today: Flow<LocalDate> = callbackFlow {
+        val receiver = object : BroadcastReceiver() {
+            override fun onReceive(context: Context, intent: Intent) {
+                trySend(Unit)
+            }
+        }
+        val filter = IntentFilter().apply {
+            addAction(Intent.ACTION_DATE_CHANGED)
+            addAction(Intent.ACTION_TIME_CHANGED)
+            addAction(Intent.ACTION_TIMEZONE_CHANGED)
+        }
+        ContextCompat.registerReceiver(context, receiver, filter, ContextCompat.RECEIVER_NOT_EXPORTED)
+        awaitClose { context.unregisterReceiver(receiver) }
+    }
+        .onStart { emit(Unit) }
+        .transformLatest {
+            while (true) {
+                emit(currentDate())
+                delay(MINUTE_MILLIS - Clock.System.now().toEpochMilliseconds() % MINUTE_MILLIS)
+            }
+        }
+        .distinctUntilChanged()
+}
+
+private const val MINUTE_MILLIS = 60_000L
+
+fun currentDate(): LocalDate = Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault()).date

app/src/main/java/de/jeanlucmakiola/calendula/ui/CalendarHost.kt

@@ -150,6 +150,15 @@ fun CalendarHost(
     // The date every view opens on and carries along (#184); tapping a day
     // anywhere focuses it and opens the day view there.
     val focus = rememberSaveable(saver = ViewFocusSaver) { ViewFocus(localToday()) }
+    // A focus still on yesterday follows the date over, so the next view opened
+    // doesn't land on the old day (#373); one moved elsewhere stays put.
+    val today = viewModel.today.collectAsStateWithLifecycle().value
+    var focusToday by rememberSaveable { mutableStateOf(today.toString()) }
+    LaunchedEffect(today) {
+        val old = LocalDate.parse(focusToday)
+        if (old != today && focus.date == old) focus.date = today
+        focusToday = today.toString()
+    }
 
     val switchScope = rememberCoroutineScope()
     val switchTo: ((List<CalendarView>) -> List<CalendarView>) -> Unit = { move ->

app/src/main/java/de/jeanlucmakiola/calendula/ui/CalendarHostViewModel.kt

@@ -4,12 +4,15 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
+import de.jeanlucmakiola.calendula.data.time.TodaySource
+import de.jeanlucmakiola.calendula.data.time.currentDate
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.IMPLEMENTED_VIEWS
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.stateIn
+import kotlinx.datetime.LocalDate
 import javax.inject.Inject
 
 /**
@@ -21,8 +24,16 @@ import javax.inject.Inject
 @HiltViewModel
 class CalendarHostViewModel @Inject constructor(
     prefs: SettingsPrefs,
+    todaySource: TodaySource,
 ) : ViewModel() {
 
+    /** Today, kept current across midnight so the shared focus can follow it (#373). */
+    val today: StateFlow<LocalDate> = todaySource.today.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.WhileSubscribed(5_000L),
+        initialValue = currentDate(),
+    )
+
     val defaultView: StateFlow<CalendarView?> = prefs.defaultView.stateIn(
         scope = viewModelScope,
         started = SharingStarted.WhileSubscribed(5_000L),

app/src/main/java/de/jeanlucmakiola/calendula/ui/agenda/AgendaViewModel.kt

@@ -8,6 +8,8 @@ import de.jeanlucmakiola.calendula.data.di.IoDispatcher
 import de.jeanlucmakiola.calendula.data.prefs.PastEventDisplay
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 import de.jeanlucmakiola.calendula.data.prefs.firstDayOfWeek
+import de.jeanlucmakiola.calendula.data.time.TodaySource
+import de.jeanlucmakiola.calendula.data.time.currentDate
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.domain.FailureReason
@@ -21,6 +23,7 @@ import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.datetime.DateTimeUnit
 import kotlinx.datetime.DayOfWeek
@@ -30,8 +33,6 @@ import kotlinx.datetime.atStartOfDayIn
 import kotlinx.datetime.atTime
 import kotlinx.datetime.plus
 import kotlinx.datetime.toInstant
-import kotlinx.datetime.toLocalDateTime
-import kotlin.time.Clock
 import kotlin.time.Instant
 import javax.inject.Inject
 
@@ -40,6 +41,7 @@ import javax.inject.Inject
 class AgendaViewModel @Inject constructor(
     private val repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     @IoDispatcher private val io: CoroutineDispatcher,
 ) : ViewModel() {
 
@@ -84,11 +86,25 @@ class AgendaViewModel @Inject constructor(
     private val zone = TimeZone.currentSystemDefault()
 
     private val todayDate: LocalDate
-        get() = Clock.System.now().toLocalDateTime(zone).date
+        get() = currentDate()
 
     private val _anchor = MutableStateFlow(todayDate)
     val anchor: StateFlow<LocalDate> = _anchor
 
+    private var lastToday = todayDate
+
+    /**
+     * Today, kept current across midnight (#373). An agenda still starting on
+     * yesterday moves on to the new day; one jumped elsewhere stays put.
+     */
+    private val today: StateFlow<LocalDate> = todaySource.today
+        .onEach { date ->
+            val old = lastToday
+            lastToday = date
+            if (old != date && _anchor.value == old) _anchor.value = date
+        }
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000L), todayDate)
+
     // A transient, in-view override of the saved agenda range. Held in memory
     // (not persisted), so it survives view switches and rotation within the
     // session but resets to the saved default when the app is relaunched.
@@ -113,8 +129,9 @@ class AgendaViewModel @Inject constructor(
             combine(
                 repository.calendars(),
                 repository.instances(window),
-            ) { calendars, instances ->
-                buildState(params, calendars, instances)
+                today,
+            ) { calendars, instances, today ->
+                buildState(params, calendars, instances, today)
             }
         }
         .catch { emit(AgendaUiState.Failure(FailureReason.ProviderUnavailable)) }
@@ -156,6 +173,7 @@ class AgendaViewModel @Inject constructor(
         params: AgendaParams,
         calendars: List<CalendarSource>,
         instances: List<EventInstance>,
+        today: LocalDate,
     ): AgendaUiState {
         calendarListFailure(calendars)?.let { return AgendaUiState.Failure(it) }
         val anchor = params.anchor
@@ -166,7 +184,7 @@ class AgendaViewModel @Inject constructor(
         val days = groupAgendaDays(anchor, rangeEnd, instances, zone)
         return AgendaUiState.Success(
             anchor = anchor,
-            today = todayDate,
+            today = today,
             days = days,
             range = params.range,
             rangeIsOverride = params.rangeIsOverride,

app/src/main/java/de/jeanlucmakiola/calendula/ui/month/MonthScreen.kt

@@ -87,6 +87,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.compositionLocalOf
 import androidx.compose.runtime.staticCompositionLocalOf
 import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
@@ -197,13 +198,17 @@ import kotlinx.datetime.TimeZone
 import kotlinx.datetime.plus
 import kotlinx.datetime.YearMonth
 import kotlinx.datetime.toJavaLocalDate
-import kotlinx.datetime.toLocalDateTime
-import kotlin.time.Clock
 import kotlin.time.Instant
 import java.time.format.TextStyle as JavaTextStyle
 import java.util.Locale
 
 private val LocalTodayPulse = staticCompositionLocalOf { 0 }
+
+/** Live today for the pages, whose cached states may have been built before midnight (#373). */
+private val LocalMonthToday = compositionLocalOf<LocalDate?> { null }
+
+private fun MonthUiState.Success.withToday(today: LocalDate?): MonthUiState.Success =
+    if (today == null || today == this.today) this else copy(today = today)
 private val LocalOpenWeek = staticCompositionLocalOf<((LocalDate) -> Unit)?> { null }
 
 /** A brief push from today's full cell into its immediate neighbours. */
@@ -319,12 +324,7 @@ fun MonthScreen(
     }
     val dense = viewStyle == MonthViewStyle.Dense
 
-    // Today, from whichever state is driving; the clock only covers the first
-    // frame, before either has loaded.
-    val today = when {
-        scrolling -> (continuousState as? ContinuousMonthUiState.Success)?.today
-        else -> (state as? MonthUiState.Success)?.today
-    } ?: Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault()).date
+    val today by viewModel.today.collectAsStateWithLifecycle()
 
     // The two scrolling styles index their items differently — Continuous by
     // month (which the week start can't move), Dense by week (which it can) — so
@@ -520,6 +520,7 @@ fun MonthScreen(
                 LocalDimCutoff provides dimCutoff,
                 LocalMonthDrag provides chipDrag,
                 LocalTodayPulse provides todayPulse,
+                LocalMonthToday provides today,
                 LocalOpenWeek provides onOpenWeek,
             ) {
                 if (scrolling) {
@@ -773,6 +774,7 @@ private fun MonthPage(
 ) {
     val ym = yearMonthForIndex(index)
     val state by remember(ym, weekStart) { monthState(ym, weekStart) }.collectAsStateWithLifecycle()
+    val today = LocalMonthToday.current
     val chipDrag = LocalMonthDrag.current
     val morph = LocalMonthMorph.current
     val viewMorph = LocalViewMorph.current
@@ -782,7 +784,7 @@ private fun MonthPage(
         LocalViewMorph provides viewMorph.takeIf { morphActive },
     ) {
         when (val s = state) {
-            is MonthUiState.Success -> page(index, s)
+            is MonthUiState.Success -> page(index, s.withToday(today))
             else -> loading()
         }
     }
@@ -1388,7 +1390,8 @@ private fun SplitMonthContent(
             val ym = yearMonthForIndex(index)
             val pageState by remember(ym, weekStart) { monthState(ym, weekStart) }
                 .collectAsStateWithLifecycle()
-            val page = pageState as? MonthUiState.Success ?: return@HorizontalPager
+            val page = (pageState as? MonthUiState.Success)?.withToday(LocalMonthToday.current)
+                ?: return@HorizontalPager
             // Only the settled page carries the drag and the morph tags: its
             // neighbours repeat some of its dates and would claim them.
             val active = index == pagerState.settledPage

app/src/main/java/de/jeanlucmakiola/calendula/ui/month/MonthViewModel.kt

@@ -7,6 +7,8 @@ import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
 import de.jeanlucmakiola.calendula.data.di.IoDispatcher
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 import de.jeanlucmakiola.calendula.data.prefs.firstDayOfWeek
+import de.jeanlucmakiola.calendula.data.time.TodaySource
+import de.jeanlucmakiola.calendula.data.time.currentDate
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.domain.FailureReason
@@ -45,7 +47,6 @@ import kotlinx.datetime.minus
 import kotlinx.datetime.plus
 import kotlinx.datetime.toInstant
 import kotlinx.datetime.toLocalDateTime
-import kotlin.time.Clock
 import kotlin.time.Instant
 import javax.inject.Inject
 
@@ -57,6 +58,7 @@ private const val MONTH_CACHE_SPAN = 2
 class MonthViewModel @Inject constructor(
     private val repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     @IoDispatcher private val io: CoroutineDispatcher,
 ) : ViewModel() {
 
@@ -90,7 +92,18 @@ class MonthViewModel @Inject constructor(
         )
 
     private val todayDate: LocalDate
-        get() = Clock.System.now().toLocalDateTime(zone).date
+        get() = currentDate()
+
+    private var lastToday = todayDate
+
+    /** Today, kept current across midnight so a grid left open doesn't mark yesterday (#373). */
+    val today: StateFlow<LocalDate> = todaySource.today
+        .onEach { date ->
+            val old = lastToday
+            lastToday = date
+            if (old != date) followToday(old, date)
+        }
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000L), todayDate)
 
     private val _month = MutableStateFlow(YearMonth(todayDate.year, todayDate.month))
     val month: StateFlow<YearMonth> = _month
@@ -139,8 +152,9 @@ class MonthViewModel @Inject constructor(
         combine(
             repository.calendars(),
             repository.instances(monthGridRange(ym, ws, zone)),
-        ) { calendars, instances ->
-            buildState(ym, ws, calendars, instances)
+            today,
+        ) { calendars, instances, today ->
+            buildState(ym, ws, calendars, instances, today)
         }
             .catch { emit(MonthUiState.Failure(FailureReason.ProviderUnavailable)) }
             .flowOn(io)
@@ -211,8 +225,9 @@ class MonthViewModel @Inject constructor(
                 combine(
                     repository.calendars(),
                     repository.instances(range),
-                ) { calendars, instances ->
-                    buildContinuousState(window, ws, style, calendars, instances)
+                    today,
+                ) { calendars, instances, today ->
+                    buildContinuousState(window, ws, style, calendars, instances, today)
                 }
             }
             // A load landing is the cue to reach further out. Widening from here
@@ -257,6 +272,7 @@ class MonthViewModel @Inject constructor(
         style: MonthViewStyle,
         calendars: List<CalendarSource>,
         instances: List<EventInstance>,
+        today: LocalDate,
     ): ContinuousMonthUiState {
         calendarListFailure(calendars)?.let { return ContinuousMonthUiState.Failure(it) }
         // Bucketed once for the whole window: a row then takes the handful of
@@ -283,7 +299,7 @@ class MonthViewModel @Inject constructor(
             emptyMap()
         }
         return ContinuousMonthUiState.Success(
-            today = todayDate,
+            today = today,
             monthsByIndex = months,
             weeksByIndex = weeks,
             weekStart = weekStart,
@@ -333,6 +349,18 @@ class MonthViewModel @Inject constructor(
         _selectedDate.value = null
     }
 
+    /**
+     * The date rolled over from [old] to [new]. A paged grid still on [old]'s
+     * month moves on to [new]'s and drops the day picked yesterday; one browsed
+     * elsewhere stays put. The scrolling styles only repaint the today marker.
+     */
+    private fun followToday(old: LocalDate, new: LocalDate) {
+        if (viewStyle.value.isScrolling) return
+        if (_month.value != YearMonth(old.year, old.month)) return
+        _month.value = YearMonth(new.year, new.month)
+        _selectedDate.value = null
+    }
+
     /**
      * Track [_month] to the month a scrolling style is showing. Those styles
      * navigate by scroll position and never set [_month] themselves, so it would
@@ -358,12 +386,13 @@ class MonthViewModel @Inject constructor(
         weekStart: DayOfWeek,
         calendars: List<CalendarSource>,
         instances: List<EventInstance>,
+        today: LocalDate,
     ): MonthUiState {
         calendarListFailure(calendars)?.let { return MonthUiState.Failure(it) }
         val weeks = layoutMonthWeeks(ym, weekStart, instances, zone)
         return MonthUiState.Success(
             month = ym,
-            today = todayDate,
+            today = today,
             weeks = weeks,
             instancesByDay = instancesByDay(weeks.flatMap { it.days }, instances, zone),
             zone = zone,

app/src/main/java/de/jeanlucmakiola/calendula/ui/week/WeekScreen.kt

@@ -461,6 +461,7 @@ private fun PagedTimelineScreen(
         CompositionLocalProvider(LocalDimCutoff provides dimCutoff) {
             WeekContent(
                 state = state,
+                today = today,
                 pagerState = pagerState,
                 grid = grid,
                 kind = kind,
@@ -482,6 +483,7 @@ private fun PagedTimelineScreen(
 @Composable
 private fun WeekContent(
     state: WeekUiState,
+    today: LocalDate,
     pagerState: PagerState,
     grid: PageGrid,
     kind: TimelineKind,
@@ -536,7 +538,7 @@ private fun WeekContent(
                     is WeekUiState.Success -> if (morph != null) {
                         TimelineMorphFrame(
                             morph = morph,
-                            today = s.today,
+                            today = today,
                             scrollState = scrollState,
                             dragController = dragController,
                             onEventClick = onEventClick,
@@ -549,7 +551,7 @@ private fun WeekContent(
                         grid = grid,
                         kind = kind,
                         span = span,
-                        today = s.today,
+                        today = today,
                         initialStripHeight = handoffStrip ?: s.allDayStripHeight(),
                         scrollState = scrollState,
                         dragController = dragController,
@@ -618,7 +620,10 @@ private fun WeekPager(
             }
             ViewMorphPage(active = morphPageActive(page, pagerState.settledPage)) {
                 WeekPage(
-                    state = loaded ?: empty,
+                    // A cached page may predate midnight; today comes off the clock (#373).
+                    state = remember(loaded, empty, today) {
+                        loaded?.takeIf { it.today != today }?.copy(today = today) ?: loaded ?: empty
+                    },
                     headerBias = kind.headerBias,
                     allDayHeight = allDayHeight,
                     scrollState = scrollState,

app/src/main/java/de/jeanlucmakiola/calendula/ui/week/WeekViewModel.kt

@@ -7,6 +7,8 @@ import de.jeanlucmakiola.calendula.data.calendar.CalendarRepository
 import de.jeanlucmakiola.calendula.data.di.IoDispatcher
 import de.jeanlucmakiola.calendula.data.prefs.SettingsPrefs
 import de.jeanlucmakiola.calendula.data.prefs.resolveFirstDay
+import de.jeanlucmakiola.calendula.data.time.TodaySource
+import de.jeanlucmakiola.calendula.data.time.currentDate
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.domain.displayPriority
@@ -27,6 +29,7 @@ import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.flowOn
 import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.datetime.DateTimeUnit
 import kotlinx.datetime.DayOfWeek
@@ -40,7 +43,6 @@ import kotlinx.datetime.plus
 import kotlinx.datetime.toInstant
 import kotlinx.datetime.toLocalDateTime
 import java.util.Locale
-import kotlin.time.Clock
 import kotlin.time.Instant
 import javax.inject.Inject
 import kotlin.math.abs
@@ -73,6 +75,7 @@ fun positionOf(anchor: LocalDate, rule: (LocalDate) -> PageGrid): PagerPosition
 abstract class PagedTimelineViewModel(
     private val repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     private val io: CoroutineDispatcher,
     gridRule: Flow<(LocalDate) -> PageGrid>,
     initialRule: (LocalDate) -> PageGrid,
@@ -89,7 +92,7 @@ abstract class PagedTimelineViewModel(
         )
 
     private val todayDate: LocalDate
-        get() = Clock.System.now().toLocalDateTime(zone).date
+        get() = currentDate()
 
     // A day on the visible page; the page itself comes from the grid, so a
     // settings change re-frames the same days instead of jumping.
@@ -103,6 +106,17 @@ abstract class PagedTimelineViewModel(
     val rule: StateFlow<(LocalDate) -> PageGrid> =
         gridRule.stateIn(viewModelScope, SharingStarted.Eagerly, initialRule)
 
+    private var lastToday = todayDate
+
+    /** Today, kept current across midnight so a page left open doesn't mark yesterday (#373). */
+    private val today: StateFlow<LocalDate> = todaySource.today
+        .onEach { date ->
+            val old = lastToday
+            lastToday = date
+            if (old != date) followToday(old, date)
+        }
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000L), todayDate)
+
     private val position: StateFlow<PagerPosition> =
         combine(_anchor, rule) { anchor, rule -> positionOf(anchor, rule) }
             .distinctUntilChanged()
@@ -141,8 +155,9 @@ abstract class PagedTimelineViewModel(
         combine(
             repository.calendars(),
             repository.instances(spanRange(span.start, span.count, zone)),
-        ) { calendars, instances ->
-            buildState(span, calendars, instances)
+            today,
+        ) { calendars, instances, today ->
+            buildState(span, calendars, instances, today)
         }
             .catch { emit(WeekUiState.Failure(FailureReason.ProviderUnavailable)) }
             .flowOn(io)
@@ -163,12 +178,20 @@ abstract class PagedTimelineViewModel(
     }
 
     fun goToToday() = jumpTo(todayDate)
+
+    /** The date rolled over; a page still showing [old] follows on to [new], one browsed elsewhere stays. */
+    private fun followToday(old: LocalDate, new: LocalDate) {
+        val anchor = _anchor.value
+        val grid = rule.value(anchor)
+        if (grid.pageFor(anchor) == grid.pageFor(old)) _anchor.value = new
+    }
     fun goToDate(date: LocalDate) = jumpTo(date)
 
     private fun buildState(
         span: DaySpan,
         calendars: List<CalendarSource>,
         instances: List<EventInstance>,
+        today: LocalDate,
     ): WeekUiState {
         calendarListFailure(calendars)?.let { return WeekUiState.Failure(it) }
         val days = (0 until span.count).map { span.start.plus(it, DateTimeUnit.DAY) }
@@ -176,7 +199,7 @@ abstract class PagedTimelineViewModel(
         val timed = instances.filterNot { it.isAllDay }
         return WeekUiState.Success(
             weekStart = span.start,
-            today = todayDate,
+            today = today,
             days = days,
             allDaySpans = layoutAllDay(allDay, days, zone),
             timedByDay = days.associateWith { day -> layoutDay(timed, day, zone) },
@@ -189,10 +212,12 @@ abstract class PagedTimelineViewModel(
 class WeekViewModel @Inject constructor(
     repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     @IoDispatcher io: CoroutineDispatcher,
 ) : PagedTimelineViewModel(
     repository = repository,
     settingsPrefs = settingsPrefs,
+    todaySource = todaySource,
     io = io,
     gridRule = settingsPrefs.weekStart.map { pref ->
         val grid = WeekGrid(pref.resolveFirstDay(Locale.getDefault()))
@@ -211,10 +236,12 @@ class WeekViewModel @Inject constructor(
 class MultiDayViewModel @Inject constructor(
     repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     @IoDispatcher io: CoroutineDispatcher,
 ) : PagedTimelineViewModel(
     repository = repository,
     settingsPrefs = settingsPrefs,
+    todaySource = todaySource,
     io = io,
     gridRule = settingsPrefs.multiDayCount.map { count ->
         { anchor: LocalDate -> DaysGrid.startingAt(anchor, count) }
@@ -227,10 +254,12 @@ class MultiDayViewModel @Inject constructor(
 class DayViewModel @Inject constructor(
     repository: CalendarRepository,
     settingsPrefs: SettingsPrefs,
+    todaySource: TodaySource,
     @IoDispatcher io: CoroutineDispatcher,
 ) : PagedTimelineViewModel(
     repository = repository,
     settingsPrefs = settingsPrefs,
+    todaySource = todaySource,
     io = io,
     gridRule = flowOf { _: LocalDate -> DayGrid },
     initialRule = { DayGrid },