chore(release): prepare v2.9.0

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,41 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.9.0] — 2026-06-25
+
+### Added
+- Choose the view Calendula opens on. A new **Default view** setting (Settings →
+  Appearance) lets you pick Month, Week, Day or Agenda as the view shown each
+  time you start the app, instead of always opening on Week. Thanks to
+  @devinside for the suggestion ([#1]).
+- The month widget is now interactive: tap any day to open it, or tap an event to
+  open its details. Previously only the month's prev/next/today controls
+  responded. Thanks to @devinside for spotting this ([#2]).
+- Predictive back. Swiping back from a screen — an event, the editor, search or
+  settings — now follows your finger, shrinking the screen to preview what's
+  behind so you can see where Back will take you before you let go; slide it back
+  to cancel. The preview needs Android 14 or newer; on older versions Back works
+  as before.
+- Respect for "Remove animations". If you've turned animations off in your
+  device's Accessibility settings, Calendula now honours it everywhere: motion
+  collapses to a quick fade and the back preview is skipped.
+
+### Changed
+- Smoother, more consistent motion throughout. Expanding sections, list updates
+  in search and agenda, and the onboarding screens now animate the same way
+  across the app, instead of some places sliding or growing while others popped
+  in. Switching between Month, Week, Day and Agenda now cross-fades rather than
+  snapping, while paging within a view keeps its slide.
+
+### Fixed
+- Home-screen widgets now back out the way you came in. A day or event opened
+  from the Agenda widget keeps you in the agenda context, and from the Month
+  widget in the month context — pressing Back returns there instead of dropping
+  you on the week view. More broadly, the app now keeps a real view history:
+  switching views and drilling into a day are retraced by Back one step at a
+  time, down to your default view before the app exits. Thanks to @devinside for
+  reporting ([#2]).
+
 ## [2.8.0] — 2026-06-23
 
 ### Added
@@ -572,3 +607,6 @@ automatically, with zero telemetry and no internet permission.
 - Gitea release workflow: signed release APK + F-Droid metadata sync to Hetzner
 - F-Droid metadata stubs (DE + EN short/full descriptions)
 - `.planning/` project-tracking documents
+
+[#1]: https://codeberg.org/jlmakiola/calendula/issues/1
+[#2]: https://codeberg.org/jlmakiola/calendula/issues/2

app/build.gradle.kts

@@ -28,8 +28,8 @@ android {
         // which builds this version and then creates the matching vX.Y.Z tag +
         // release itself (versionCode is pinned to MAJOR*10000 + MINOR*100 +
         // PATCH from versionName, e.g. 2.7.2 -> 20702). See docs/RELEASING.md.
-        versionCode = 20800
+        versionCode = 20900
-        versionName = "2.8.0"
+        versionName = "2.9.0"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }

app/src/main/AndroidManifest.xml

@@ -39,6 +39,7 @@
     <application
         android:name=".CalendulaApp"
         android:allowBackup="true"
+        android:enableOnBackInvokedCallback="true"
         android:dataExtractionRules="@xml/data_extraction_rules"
         android:fullBackupContent="@xml/backup_rules"
         android:icon="@mipmap/ic_launcher"

app/src/main/java/de/jeanlucmakiola/calendula/MainActivity.kt

@@ -22,6 +22,7 @@ import de.jeanlucmakiola.calendula.data.crash.CrashReporter
 import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.calendula.ui.RootScreen
 import de.jeanlucmakiola.calendula.ui.WidgetNavRequest
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.crash.CrashReportActivity
 import de.jeanlucmakiola.calendula.ui.crash.CrashReportDialog
 import de.jeanlucmakiola.calendula.ui.crash.submitCrashReport
@@ -140,18 +141,38 @@ class MainActivity : AppCompatActivity() {
         return uri.takeIf { it.scheme == "content" || it.scheme == "file" }
     }
 
-    private fun Intent.navRequestOrNull(): WidgetNavRequest? = when {
+    private fun Intent.navRequestOrNull(): WidgetNavRequest? {
+        val source = sourceViewOrNull()
+        val eventId = getLongExtra(EXTRA_EVENT_ID, -1L)
+        return when {
             // Launcher long-press "New event" shortcut. Static shortcut intents
             // can't carry typed extras, so the action alone signals create-on-today.
             action == ACTION_NEW_EVENT -> WidgetNavRequest.Create(null)
             getBooleanExtra(EXTRA_CREATE, false) ->
                 WidgetNavRequest.Create(getStringExtra(EXTRA_DATE_ISO))
-        getStringExtra(EXTRA_DATE_ISO) != null ->
+            // A widget event tap carries both the occurrence and its source view;
-            WidgetNavRequest.OpenDate(getStringExtra(EXTRA_DATE_ISO)!!)
+            // reminders (no source) fall through to [detailKeyOrNull] instead.
+            source != null && eventId != -1L -> WidgetNavRequest.OpenEvent(
+                eventId = eventId,
+                beginMillis = getLongExtra(EXTRA_BEGIN_MILLIS, 0L),
+                endMillis = getLongExtra(EXTRA_END_MILLIS, 0L),
+                source = source,
+            )
+            source != null && getStringExtra(EXTRA_DATE_ISO) != null ->
+                WidgetNavRequest.OpenDate(getStringExtra(EXTRA_DATE_ISO)!!, source)
             else -> null
         }
+    }
+
+    /** The view the launching widget represents, if any (see [EXTRA_SOURCE_VIEW]). */
+    private fun Intent.sourceViewOrNull(): CalendarView? =
+        getStringExtra(EXTRA_SOURCE_VIEW)
+            ?.let { name -> CalendarView.entries.firstOrNull { it.name == name } }
 
     private fun Intent.detailKeyOrNull(): LongArray? {
+        // A widget event tap (source present) is routed through [navRequestOrNull]
+        // so it can also set the base view; only sourceless reminder taps land here.
+        if (sourceViewOrNull() != null) return null
         val eventId = getLongExtra(EXTRA_EVENT_ID, -1L)
         if (eventId == -1L) return null
         return longArrayOf(
@@ -168,6 +189,10 @@ class MainActivity : AppCompatActivity() {
         private const val EXTRA_DATE_ISO = "de.jeanlucmakiola.calendula.extra.DATE_ISO"
         private const val EXTRA_CREATE = "de.jeanlucmakiola.calendula.extra.CREATE"
 
+        // The [CalendarView] (by name) of the widget a launch came from. Roots the
+        // in-app back stack in that view; absent for non-widget launches (reminders).
+        private const val EXTRA_SOURCE_VIEW = "de.jeanlucmakiola.calendula.extra.SOURCE_VIEW"
+
         // Fired by the launcher long-press "New event" shortcut (res/xml/
         // shortcuts.xml hardcodes this string — keep the two in sync).
         const val ACTION_NEW_EVENT = "de.jeanlucmakiola.calendula.action.NEW_EVENT"
@@ -190,14 +215,35 @@ class MainActivity : AppCompatActivity() {
             addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
         }
 
-        /** Open the day view anchored on [date] (home-screen widgets). */
+        /**
-        fun openDateIntent(context: Context, date: LocalDate): Intent =
+         * Open the day view anchored on [date], drilled in over the launching
+         * widget's [source] view (home-screen widgets). Backing out of the day
+         * returns to [source], then to the default home view.
+         */
+        fun openDateIntent(context: Context, date: LocalDate, source: CalendarView): Intent =
             Intent(context, MainActivity::class.java).apply {
                 data = "calendula://date/$date".toUri()
                 putExtra(EXTRA_DATE_ISO, date.toString())
+                putExtra(EXTRA_SOURCE_VIEW, source.name)
                 addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
             }
 
+        /**
+         * Open one occurrence's detail from a widget event tap, rooting the back
+         * stack in the widget's [source] view. Same occurrence-key shape as
+         * [eventDetailIntent]; the [source] extra is what distinguishes a widget
+         * tap (sets the base view) from a reminder tap (leaves it untouched).
+         */
+        fun openEventIntent(
+            context: Context,
+            eventId: Long,
+            beginMillis: Long,
+            endMillis: Long,
+            source: CalendarView,
+        ): Intent = eventDetailIntent(context, eventId, beginMillis, endMillis).apply {
+            putExtra(EXTRA_SOURCE_VIEW, source.name)
+        }
+
         /** Open the create-event form prefilled for [date] (home-screen widgets). */
         fun openCreateIntent(context: Context, date: LocalDate): Intent =
             Intent(context, MainActivity::class.java).apply {

app/src/main/java/de/jeanlucmakiola/calendula/data/prefs/SettingsPrefs.kt

@@ -7,6 +7,7 @@ import androidx.datastore.preferences.core.edit
 import androidx.datastore.preferences.core.intPreferencesKey
 import androidx.datastore.preferences.core.stringPreferencesKey
 import de.jeanlucmakiola.calendula.domain.EventFormField
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import kotlinx.datetime.DayOfWeek
@@ -69,6 +70,20 @@ class SettingsPrefs @Inject constructor(
         store.edit { it[WEEK_START_KEY] = pref.name }
     }
 
+    /**
+     * The calendar view the app opens on (M1). Defaults to [CalendarView.Week] —
+     * the historical hard-coded startup view — so existing users see no change
+     * until they pick another. Also the bottom of the in-app view back stack, so
+     * back from any other view returns here before exiting.
+     */
+    val defaultView: Flow<CalendarView> = store.data.map { prefs ->
+        prefs[DEFAULT_VIEW_KEY].toEnum(CalendarView.Week)
+    }
+
+    suspend fun setDefaultView(view: CalendarView) {
+        store.edit { it[DEFAULT_VIEW_KEY] = view.name }
+    }
+
     /**
      * Optional event-form fields shown by default (the rest hide behind
      * "more fields"). Stored comma-joined by enum name: an absent key means
@@ -244,6 +259,7 @@ class SettingsPrefs @Inject constructor(
         internal val THEME_MODE_KEY = stringPreferencesKey("theme_mode")
         internal val DYNAMIC_COLOR_KEY = booleanPreferencesKey("dynamic_color")
         internal val WEEK_START_KEY = stringPreferencesKey("week_start")
+        internal val DEFAULT_VIEW_KEY = stringPreferencesKey("default_view")
         internal val FORM_FIELDS_KEY = stringPreferencesKey("event_form_default_fields")
         internal val REMINDERS_ENABLED_KEY = booleanPreferencesKey("reminders_enabled")
         internal val REMINDER_ONBOARDING_KEY = booleanPreferencesKey("reminder_onboarding_done")

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

@@ -1,5 +1,7 @@
 package de.jeanlucmakiola.calendula.ui
 
+import androidx.activity.compose.BackHandler
+import androidx.compose.animation.AnimatedContent
 import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.animation.fadeIn
 import androidx.compose.animation.fadeOut
@@ -12,15 +14,22 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.listSaver
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
+import androidx.hilt.navigation.compose.hiltViewModel
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.domain.EventForm
 import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.ui.agenda.AgendaScreen
 import de.jeanlucmakiola.calendula.ui.calendars.CalendarsScreen
+import de.jeanlucmakiola.calendula.ui.common.calendarFadeThrough
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
+import de.jeanlucmakiola.calendula.ui.common.drillToDay
 import de.jeanlucmakiola.calendula.ui.common.rememberCalendarSlideSpec
+import de.jeanlucmakiola.calendula.ui.common.selectView
+import de.jeanlucmakiola.calendula.ui.common.viewBaseStack
 import de.jeanlucmakiola.calendula.ui.day.DayScreen
 import de.jeanlucmakiola.calendula.ui.detail.EventDetailScreen
 import de.jeanlucmakiola.calendula.ui.edit.EventEditScreen
@@ -35,14 +44,24 @@ import kotlinx.datetime.toLocalDateTime
 import kotlin.time.Clock
 
 /**
- * Holds the active top-level view (spec M1) and swaps between the calendar
+ * Holds the top-level view back stack (spec M1) and swaps between the calendar
  * screens. Each screen owns its own ViewModel and date anchor; the view-switcher
  * pill in their top bars writes back here via [onSelectView].
  *
+ * The stack's bottom is the user's [CalendarHostViewModel.defaultView] home view.
+ * A lateral switch (pill / drawer) builds a visit history so back retraces it
+ * (see [selectView]); a widget launch resets the stack to its own view; a date
+ * tap drills the day view on top. Pressing back pops one level, and the
+ * base-level [BackHandler] hands off to the system to exit once only the home
+ * view remains. So back from a widget-opened screen returns to that widget's
+ * view, then home; and back through pill switches walks the views in reverse.
+ *
  * [requestedDetailKey] is an externally requested occurrence (a tapped
  * reminder notification routed through MainActivity): it opens the detail
  * overlay exactly like an event tap and is cleared via [onDetailKeyConsumed]
- * so a later recomposition can't re-open it.
+ * so a later recomposition can't re-open it. (A widget event tap instead arrives
+ * as [WidgetNavRequest.OpenEvent], which also roots the back stack in the
+ * widget's view.)
  */
 @Composable
 fun CalendarHost(
@@ -53,15 +72,24 @@ fun CalendarHost(
     onWidgetNavConsumed: () -> Unit = {},
     requestedImportUri: android.net.Uri? = null,
     onImportConsumed: () -> Unit = {},
+    viewModel: CalendarHostViewModel = hiltViewModel(),
 ) {
-    var view by rememberSaveable { mutableStateOf(CalendarView.Week) }
+    // Wait for the persisted default view before seeding the stack, so the app
-    val onSelectView: (CalendarView) -> Unit = { view = it }
+    // opens straight on the user's choice instead of flashing a placeholder and
+    // correcting it. Brief blank first frame, matching the onboarding gate above.
+    val defaultView = viewModel.defaultView.collectAsStateWithLifecycle().value ?: return
+
+    var viewStack by rememberSaveable(stateSaver = viewStackSaver) {
+        mutableStateOf(listOf(defaultView))
+    }
+    val view = viewStack.last()
+    val onSelectView: (CalendarView) -> Unit = { viewStack = viewStack.selectView(it) }
 
     // Tapping a day in the month grid opens the day view anchored to that date.
     var pendingDayIso by rememberSaveable { mutableStateOf<String?>(null) }
     val onOpenDay: (LocalDate) -> Unit = { date ->
         pendingDayIso = date.toString()
-        view = CalendarView.Day
+        viewStack = viewStack.drillToDay()
     }
 
     // The event-detail screen (S4) is a full-screen destination hoisted here so
@@ -156,17 +184,30 @@ fun CalendarHost(
         importForm = null
     }
 
-    // A home-screen widget launch asks to open a date (→ day view) or start a
+    // A home-screen widget launch asks to open a date (→ day view), open an
-    // create. Handled once and cleared, mirroring [requestedDetailKey].
+    // event's detail, or start a create. Handled once and cleared, mirroring
+    // [requestedDetailKey]. Date/event opens root the stack in the widget's own
+    // view so backing out returns there (then home), not to the default.
     LaunchedEffect(widgetNavRequest) {
         when (val req = widgetNavRequest) {
             is WidgetNavRequest.OpenDate -> {
-                // Reveal the day view: drop any overlay that would cover it, so
+                // Drill the day view in over the widget's view: drop any overlay
-                // an external date-open doesn't land under an open Settings/form.
+                // that would cover it, so the open doesn't land under Settings/form.
                 dismissCoveringOverlays()
                 createDateIso = null
                 pendingDayIso = req.dateIso
-                view = CalendarView.Day
+                viewStack = viewBaseStack(defaultView, req.source).drillToDay()
+                onWidgetNavConsumed()
+            }
+            is WidgetNavRequest.OpenEvent -> {
+                // Root the stack in the widget's view, then open the occurrence
+                // detail over it (same key shape as a tapped event / reminder).
+                dismissCoveringOverlays()
+                createDateIso = null
+                viewStack = viewBaseStack(defaultView, req.source)
+                val key = longArrayOf(req.eventId, req.beginMillis, req.endMillis)
+                heldKey = key
+                detailKey = key
                 onWidgetNavConsumed()
             }
             is WidgetNavRequest.Create -> {
@@ -189,10 +230,29 @@ fun CalendarHost(
 
     val slideSpec = rememberCalendarSlideSpec()
 
+    // Base-level back: pop the view stack while no overlay covers it (each overlay
+    // owns its own BackHandler and takes precedence). Disabled at the home view,
+    // so back there falls through to the system and exits the app.
+    val anyOverlayVisible = showSearch || detailKey != null || createDateIso != null ||
+        editKey != null || showSettings || showCalendars || importUri != null ||
+        importForm != null
+    BackHandler(enabled = !anyOverlayVisible && viewStack.size > 1) {
+        viewStack = viewStack.dropLast(1)
+    }
+
     Box(modifier = modifier.fillMaxSize()) {
-        when (view) {
+        // Switching between the peer views (month/week/day/agenda) is lateral
+        // navigation, so it fades through rather than sliding — paging *within* a
+        // view keeps the directional slide. AnimatedContent keyed on the view type.
+        val viewSwitch = calendarFadeThrough()
+        AnimatedContent(
+            targetState = view,
+            transitionSpec = { viewSwitch },
+            label = "view-switch",
+        ) { currentView ->
+            when (currentView) {
                 CalendarView.Week -> WeekScreen(
-                selectedView = view,
+                    selectedView = currentView,
                     onSelectView = onSelectView,
                     onEventClick = onEventClick,
                     onOpenSettings = onOpenSettings,
@@ -200,7 +260,7 @@ fun CalendarHost(
                     onCreateEvent = onCreateEvent,
                 )
                 CalendarView.Day -> DayScreen(
-                selectedView = view,
+                    selectedView = currentView,
                     onSelectView = onSelectView,
                     onEventClick = onEventClick,
                     onOpenSettings = onOpenSettings,
@@ -209,7 +269,7 @@ fun CalendarHost(
                     initialDateIso = pendingDayIso,
                 )
                 CalendarView.Month -> MonthScreen(
-                selectedView = view,
+                    selectedView = currentView,
                     onSelectView = onSelectView,
                     onOpenDay = onOpenDay,
                     onOpenSettings = onOpenSettings,
@@ -217,7 +277,7 @@ fun CalendarHost(
                     onCreateEvent = onCreateEvent,
                 )
                 CalendarView.Agenda -> AgendaScreen(
-                selectedView = view,
+                    selectedView = currentView,
                     onSelectView = onSelectView,
                     onEventClick = onEventClick,
                     onOpenSettings = onOpenSettings,
@@ -225,6 +285,7 @@ fun CalendarHost(
                     onCreateEvent = onCreateEvent,
                 )
             }
+        }
 
         // Search overlay — below detail/edit in the Box so a tapped result's
         // detail screen draws on top, and closing it returns to the results.
@@ -338,3 +399,9 @@ fun CalendarHost(
         }
     }
 }
+
+/** Persists the view back stack across config change / process death by ordinal. */
+private val viewStackSaver = listSaver<List<CalendarView>, Int>(
+    save = { stack -> stack.map(CalendarView::ordinal) },
+    restore = { ordinals -> ordinals.map { CalendarView.entries[it] } },
+)

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

@@ -0,0 +1,29 @@
+package de.jeanlucmakiola.calendula.ui
+
+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.ui.common.CalendarView
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.stateIn
+import javax.inject.Inject
+
+/**
+ * Supplies [CalendarHost] with the user's default startup view (M1). Held as a
+ * nullable [StateFlow] so the host can wait for DataStore's first emission before
+ * seeding its view back stack — rendering nothing for that first frame rather
+ * than flashing the old hard-coded Week view and then correcting it.
+ */
+@HiltViewModel
+class CalendarHostViewModel @Inject constructor(
+    prefs: SettingsPrefs,
+) : ViewModel() {
+
+    val defaultView: StateFlow<CalendarView?> = prefs.defaultView.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.WhileSubscribed(5_000L),
+        initialValue = null,
+    )
+}

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

@@ -2,6 +2,9 @@ package de.jeanlucmakiola.calendula.ui
 
 import android.Manifest
 import android.content.pm.PackageManager
+import androidx.compose.animation.Crossfade
+import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
+import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.mutableStateOf
@@ -20,6 +23,7 @@ import de.jeanlucmakiola.calendula.ui.permission.PermissionScreen
 import de.jeanlucmakiola.calendula.ui.permission.ReminderOnboardingScreen
 import de.jeanlucmakiola.calendula.ui.permission.ReminderOnboardingViewModel
 
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
 @Composable
 fun RootScreen(
     modifier: Modifier = Modifier,
@@ -51,13 +55,19 @@ fun RootScreen(
         onDispose { lifecycle.removeObserver(obs) }
     }
 
-    if (hasPermission) {
+    // Cross-fade the one-time onboarding gates so granting permission / finishing
+    // onboarding eases into the next screen instead of snapping. A fade carries no
+    // spatial motion, so it stays appropriate under "remove animations" too.
+    val gateSpec = MaterialTheme.motionScheme.fastEffectsSpec<Float>()
+    Crossfade(targetState = hasPermission, animationSpec = gateSpec, label = "permissionGate") { granted ->
+        if (granted) {
             // Second onboarding gate (v1.4, one-time): reminder notifications.
             // Null until DataStore's first emission — render nothing for that
             // frame instead of flashing the wrong screen.
             val reminderOnboarding: ReminderOnboardingViewModel = hiltViewModel()
             val onboardingDone by reminderOnboarding.onboardingDone.collectAsStateWithLifecycle()
-        when (onboardingDone) {
+            Crossfade(targetState = onboardingDone, animationSpec = gateSpec, label = "onboardingGate") { done ->
+                when (done) {
                     true -> CalendarHost(
                         modifier = modifier,
                         requestedDetailKey = requestedDetailKey,
@@ -73,6 +83,7 @@ fun RootScreen(
                     )
                     null -> {}
                 }
+            }
         } else {
             PermissionScreen(
                 onGranted = { hasPermission = true },
@@ -80,3 +91,4 @@ fun RootScreen(
             )
         }
     }
+}

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

@@ -1,14 +1,28 @@
 package de.jeanlucmakiola.calendula.ui
 
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
+
 /**
  * A navigation a home-screen widget asked the app to perform when launched.
  * Parsed from the launch intent in MainActivity and consumed once by
- * [CalendarHost] (event taps reuse the existing reminder detail-key channel, so
+ * [CalendarHost]. Every request carries the [source] view of the widget it came
- * they are not modelled here).
+ * from (the agenda widget → [CalendarView.Agenda], the month widget →
+ * [CalendarView.Month]) so the in-app back stack roots itself in that view:
+ * backing out of the opened date/event returns to the widget's own view, not the
+ * default home. (Reminder notifications are not widgets — they keep the separate
+ * detail-key channel and leave the base view untouched.)
  */
 sealed interface WidgetNavRequest {
-    /** Open the day view anchored on [dateIso] (an ISO `yyyy-MM-dd` date). */
+    /** Open the day view anchored on [dateIso] (an ISO `yyyy-MM-dd` date), over [source]. */
-    data class OpenDate(val dateIso: String) : WidgetNavRequest
+    data class OpenDate(val dateIso: String, val source: CalendarView) : WidgetNavRequest
+
+    /** Open one occurrence's detail (an agenda-widget event tap), over [source]. */
+    data class OpenEvent(
+        val eventId: Long,
+        val beginMillis: Long,
+        val endMillis: Long,
+        val source: CalendarView,
+    ) : WidgetNavRequest
 
     /** Open the create-event form prefilled for [dateIso] (today when null). */
     data class Create(val dateIso: String?) : WidgetNavRequest

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

@@ -47,6 +47,7 @@ import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.common.calendarAnimateItem
 import de.jeanlucmakiola.calendula.ui.common.CalendarDrawer
 import de.jeanlucmakiola.calendula.ui.common.CalendarFabColumn
 import de.jeanlucmakiola.calendula.ui.common.CalendarFailure
@@ -190,6 +191,7 @@ private fun AgendaList(
                 AgendaEventRow(
                     event = event,
                     position = positionOf(index, day.events.size),
+                    modifier = calendarAnimateItem(),
                     onClick = { onEventClick(event) },
                 )
             }
@@ -221,11 +223,13 @@ private fun AgendaDayHeader(date: LocalDate, today: LocalDate) {
 private fun AgendaEventRow(
     event: EventInstance,
     position: Position,
+    modifier: Modifier = Modifier,
     onClick: () -> Unit,
 ) {
     val dark = isSystemInDarkTheme()
     val title = event.title.ifBlank { stringResource(R.string.event_untitled) }
     GroupedRow(
+        modifier = modifier,
         title = title,
         summary = agendaTimeSummary(event),
         position = position,

app/src/main/java/de/jeanlucmakiola/calendula/ui/calendars/CalendarsScreen.kt

@@ -4,7 +4,6 @@ import android.accounts.AccountManager
 import android.content.Context
 import android.content.Intent
 import android.provider.Settings
-import androidx.activity.compose.BackHandler
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.background
@@ -73,6 +72,7 @@ import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.ui.common.CALENDAR_COLOR_PALETTE
 import de.jeanlucmakiola.calendula.ui.common.CalendarColorChip
+import de.jeanlucmakiola.calendula.ui.common.predictiveBack
 import de.jeanlucmakiola.calendula.ui.common.CollapsingScaffold
 import de.jeanlucmakiola.calendula.ui.common.ColorSwatchRow
 import de.jeanlucmakiola.calendula.ui.common.GroupedRow
@@ -295,10 +295,9 @@ private fun CalendarEditor(
     var confirmDelete by remember { mutableStateOf(false) }
     val dark = isSystemInDarkTheme()
 
-    BackHandler(onBack = onClose)
-
     Scaffold(
         modifier = Modifier
+            .predictiveBack(onBack = onClose)
             .fillMaxSize()
             .background(MaterialTheme.colorScheme.surface),
         topBar = {

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/CalendarTransitions.kt

@@ -1,14 +1,56 @@
 package de.jeanlucmakiola.calendula.ui.common
 
+import android.provider.Settings
+import androidx.activity.BackEventCompat
+import androidx.activity.compose.PredictiveBackHandler
 import androidx.compose.animation.ContentTransform
+import androidx.compose.animation.EnterTransition
+import androidx.compose.animation.ExitTransition
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.FastOutSlowInEasing
 import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.expandVertically
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
+import androidx.compose.animation.shrinkVertically
 import androidx.compose.animation.slideInHorizontally
+import androidx.compose.animation.slideInVertically
 import androidx.compose.animation.slideOutHorizontally
 import androidx.compose.animation.togetherWith
+import androidx.compose.foundation.lazy.LazyItemScope
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.IntOffset
+import androidx.compose.ui.unit.dp
+import kotlin.coroutines.cancellation.CancellationException
+
+/**
+ * Whether the user has asked the system to remove animations (Settings →
+ * Accessibility → "Remove animations", which sets the global animator duration
+ * scale to 0). Compose animations do *not* honour this platform flag on their
+ * own, so the shared motion helpers in this file check it and fall back to a
+ * quick cross-fade — opacity only, no spatial movement — to respect the
+ * vestibular intent of the setting while keeping state changes legible.
+ *
+ * Read once at composition; the scale changes rarely and only takes full effect
+ * after a process restart anyway.
+ */
+@Composable
+fun rememberReduceMotion(): Boolean {
+    val resolver = LocalContext.current.contentResolver
+    return remember(resolver) {
+        Settings.Global.getFloat(resolver, Settings.Global.ANIMATOR_DURATION_SCALE, 1f) == 0f
+    }
+}
 
 /**
  * The M3 Expressive spatial spring used for the month/week slide: the *fast*
@@ -24,17 +66,160 @@ fun rememberCalendarSlideSpec(): FiniteAnimationSpec<IntOffset> =
     MaterialTheme.motionScheme.fastSpatialSpec()
 
 /**
- * Horizontal slide for navigating between adjacent months/weeks.
+ * The fast effects spec from the active motion scheme, for opacity (fade)
+ * transitions. Captured in composable scope alongside [rememberCalendarSlideSpec]
+ * for use in non-composable transition lambdas and as the reduced-motion fallback.
+ */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun rememberCalendarFadeSpec(): FiniteAnimationSpec<Float> =
+    MaterialTheme.motionScheme.fastEffectsSpec()
+
+/**
+ * Horizontal slide for navigating between adjacent months/weeks/days.
  *
  * @param slideDir     +1 = forward (incoming from the right), -1 = back, 0 = jump
  *                     (e.g. "today"); a jump reuses the forward direction.
  * @param spec         spatial animation spec, typically [rememberCalendarSlideSpec].
+ * @param fadeSpec     effects spec for the reduced-motion fade, typically
+ *                     [rememberCalendarFadeSpec].
+ * @param reduceMotion when true, swap the directional slide for a plain cross-fade.
  */
 fun calendarSlideTransition(
     slideDir: Int,
     spec: FiniteAnimationSpec<IntOffset>,
+    fadeSpec: FiniteAnimationSpec<Float>,
+    reduceMotion: Boolean,
 ): ContentTransform {
+    if (reduceMotion) {
+        return fadeIn(fadeSpec).togetherWith(fadeOut(fadeSpec))
+    }
     val dir = if (slideDir == 0) 1 else slideDir
     return slideInHorizontally(spec) { w -> dir * w }
         .togetherWith(slideOutHorizontally(spec) { w -> -dir * w })
 }
+
+/**
+ * Cross-fade [ContentTransform] for swapping whole screens or content blocks
+ * where there is no meaningful spatial direction (e.g. onboarding gates). Pure
+ * opacity, so it doubles as its own reduced-motion form.
+ */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun calendarFadeThrough(): ContentTransform {
+    val fade = MaterialTheme.motionScheme.fastEffectsSpec<Float>()
+    return fadeIn(fade).togetherWith(fadeOut(fade))
+}
+
+/**
+ * Enter transition for a vertically-revealed section (expandable rows, inline
+ * fields): height grows from the top while fading in. Under reduced motion the
+ * height growth is dropped, leaving a quick fade.
+ *
+ * Pair with [calendarCollapseExit]. This is the promoted form of the pattern
+ * originally inlined in the event edit form, so every expandable surface in the
+ * app reveals the same way.
+ */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun calendarExpandEnter(reduceMotion: Boolean = rememberReduceMotion()): EnterTransition {
+    val fade = fadeIn(MaterialTheme.motionScheme.fastEffectsSpec())
+    return if (reduceMotion) {
+        fade
+    } else {
+        expandVertically(MaterialTheme.motionScheme.fastSpatialSpec()) + fade
+    }
+}
+
+/** Exit counterpart to [calendarExpandEnter]: shrink + fade, or fade only under reduced motion. */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun calendarCollapseExit(reduceMotion: Boolean = rememberReduceMotion()): ExitTransition {
+    val fade = fadeOut(MaterialTheme.motionScheme.fastEffectsSpec())
+    return if (reduceMotion) {
+        fade
+    } else {
+        shrinkVertically(MaterialTheme.motionScheme.fastSpatialSpec()) + fade
+    }
+}
+
+/**
+ * Enter transition for content revealed by an `AnimatedContent`/`AnimatedVisibility`
+ * (e.g. search results once a query resolves): a gentle rise + fade. Reduced
+ * motion keeps the fade only.
+ */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun calendarItemEnter(reduceMotion: Boolean = rememberReduceMotion()): EnterTransition {
+    val fade = fadeIn(MaterialTheme.motionScheme.fastEffectsSpec())
+    return if (reduceMotion) {
+        fade
+    } else {
+        fade + slideInVertically(MaterialTheme.motionScheme.fastSpatialSpec()) { h -> h / 6 }
+    }
+}
+
+/**
+ * Shared [LazyItemScope.animateItem] wiring so list rows fade/relocate with the
+ * app's motion scheme instead of Compose's default spring. Returns a bare
+ * [Modifier] under reduced motion so rows snap into place. Requires the list to
+ * supply stable item keys.
+ */
+@OptIn(ExperimentalMaterial3ExpressiveApi::class)
+@Composable
+fun LazyItemScope.calendarAnimateItem(reduceMotion: Boolean = rememberReduceMotion()): Modifier =
+    if (reduceMotion) {
+        Modifier
+    } else {
+        Modifier.animateItem(
+            fadeInSpec = MaterialTheme.motionScheme.fastEffectsSpec(),
+            placementSpec = MaterialTheme.motionScheme.fastSpatialSpec(),
+            fadeOutSpec = MaterialTheme.motionScheme.fastEffectsSpec(),
+        )
+    }
+
+/**
+ * Standard Android predictive-back transform for a full-screen overlay: as the
+ * back gesture is dragged, the surface scales toward ~90%, shifts toward the
+ * swiped edge and rounds its corners, previewing what's behind. Completing the
+ * gesture invokes [onBack]; cancelling springs it back.
+ *
+ * A drop-in replacement for a screen's own `BackHandler(onBack)` — register it
+ * once and apply the returned [Modifier] to that screen's root so the preview
+ * respects the same back semantics. Under reduced motion the visual preview is
+ * skipped (the back still works); on API < 34 the system delivers no progress,
+ * so it degrades to a plain back.
+ */
+@Composable
+fun Modifier.predictiveBack(
+    onBack: () -> Unit,
+    enabled: Boolean = true,
+    reduceMotion: Boolean = rememberReduceMotion(),
+): Modifier {
+    val progress = remember { Animatable(0f) }
+    var fromLeftEdge by remember { mutableStateOf(true) }
+
+    PredictiveBackHandler(enabled = enabled) { events ->
+        try {
+            events.collect { event ->
+                fromLeftEdge = event.swipeEdge == BackEventCompat.EDGE_LEFT
+                progress.snapTo(FastOutSlowInEasing.transform(event.progress))
+            }
+            onBack()
+            progress.snapTo(0f)
+        } catch (_: CancellationException) {
+            progress.animateTo(0f)
+        }
+    }
+
+    if (reduceMotion) return this
+    return this.graphicsLayer {
+        val p = progress.value
+        val scale = 1f - 0.1f * p
+        scaleX = scale
+        scaleY = scale
+        translationX = (if (fromLeftEdge) 1f else -1f) * 24.dp.toPx() * p
+        shape = RoundedCornerShape(32.dp.toPx() * p)
+        clip = p > 0f
+    }
+}

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/CalendarView.kt

@@ -49,3 +49,31 @@ fun CalendarView.next(available: List<CalendarView> = IMPLEMENTED_VIEWS): Calend
     if (i < 0) return available.firstOrNull() ?: CalendarView.Month
     return available[(i + 1) % available.size]
 }
+
+/**
+ * The top-level view back stack (bottom → top): the [default] home view always
+ * sits at the bottom. Pressing back pops one level until only the home view
+ * remains, then the system exits the app. Three operations move it:
+ *
+ * - [selectView] — a lateral switch (the pill or the drawer). It keeps a visit
+ *   history so back retraces it: switching to a not-yet-visited view pushes it on
+ *   top; switching to one already in the stack pops back to it (collapsing the
+ *   loop, so the depth stays bounded by the number of distinct views). Selecting
+ *   the home view collapses to just `[default]`.
+ * - [viewBaseStack] — the stack a widget launch resets to: just `[default]` when
+ *   the widget's view is the home view, else `[default, source]`. A widget entry
+ *   starts a fresh context rather than extending in-app history.
+ * - [drillToDay] — pushes the day view on top (a date tap from the month grid or
+ *   a widget), unless the day view is already current.
+ */
+fun List<CalendarView>.selectView(target: CalendarView): List<CalendarView> {
+    val existing = indexOf(target)
+    return if (existing >= 0) take(existing + 1) else this + target
+}
+
+fun viewBaseStack(default: CalendarView, source: CalendarView): List<CalendarView> =
+    if (source == default) listOf(default) else listOf(default, source)
+
+/** Push the day view as a drill-in over the current stack (no-op if already on it). */
+fun List<CalendarView>.drillToDay(): List<CalendarView> =
+    if (lastOrNull() == CalendarView.Day) this else this + CalendarView.Day

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/GroupedList.kt

@@ -1,6 +1,5 @@
 package de.jeanlucmakiola.calendula.ui.common
 
-import androidx.activity.compose.BackHandler
 import androidx.compose.animation.core.animateDpAsState
 import androidx.compose.foundation.background
 import androidx.compose.foundation.interaction.MutableInteractionSource
@@ -73,11 +72,11 @@ fun CollapsingScaffold(
     actions: @Composable RowScope.() -> Unit = {},
     content: @Composable ColumnScope.() -> Unit,
 ) {
-    BackHandler(onBack = onBack)
     val scrollBehavior =
         TopAppBarDefaults.exitUntilCollapsedScrollBehavior(rememberTopAppBarState())
     Scaffold(
         modifier = modifier
+            .predictiveBack(onBack = onBack)
             .fillMaxSize()
             .background(MaterialTheme.colorScheme.surface)
             .nestedScroll(scrollBehavior.nestedScrollConnection),

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/Picker.kt

@@ -173,7 +173,11 @@ fun ReminderDefaultPicker(
             },
             onClick = { customExpanded = !customExpanded },
         )
-        AnimatedVisibility(visible = customExpanded) {
+        AnimatedVisibility(
+            visible = customExpanded,
+            enter = calendarExpandEnter(),
+            exit = calendarCollapseExit(),
+        ) {
             CustomReminderEditor(
                 amountText = amountText,
                 onAmountChange = { amountText = it },

app/src/main/java/de/jeanlucmakiola/calendula/ui/day/DayScreen.kt

@@ -75,6 +75,8 @@ import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.NowLine
 import de.jeanlucmakiola.calendula.ui.common.ViewSwitcherPill
 import de.jeanlucmakiola.calendula.ui.common.calendarSlideTransition
+import de.jeanlucmakiola.calendula.ui.common.rememberCalendarFadeSpec
+import de.jeanlucmakiola.calendula.ui.common.rememberReduceMotion
 import de.jeanlucmakiola.calendula.ui.common.next
 import de.jeanlucmakiola.calendula.ui.common.pastelize
 import de.jeanlucmakiola.calendula.ui.common.rememberCalendarSlideSpec
@@ -237,6 +239,8 @@ private fun DayContent(
     val threshold = with(density) { 24.dp.toPx() }
     var dragAccum by remember { mutableFloatStateOf(0f) }
     val slideSpec = rememberCalendarSlideSpec()
+    val fadeSpec = rememberCalendarFadeSpec()
+    val reduceMotion = rememberReduceMotion()
 
     // Hoisted above the per-day AnimatedContent so the vertical scroll position
     // survives day-to-day swipes. We only centre on noon once, on first entry
@@ -287,7 +291,7 @@ private fun DayContent(
                 DayUiState.Loading -> "loading"
             }
         },
-        transitionSpec = { calendarSlideTransition(slideDir, slideSpec) },
+        transitionSpec = { calendarSlideTransition(slideDir, slideSpec, fadeSpec, reduceMotion) },
         label = "day-transition",
     ) { s ->
         when (s) {

app/src/main/java/de/jeanlucmakiola/calendula/ui/detail/EventDetailScreen.kt

@@ -6,7 +6,6 @@ import android.content.Context
 import android.content.Intent
 import android.content.pm.PackageManager
 import android.net.Uri
-import androidx.activity.compose.BackHandler
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.background
@@ -92,6 +91,7 @@ import de.jeanlucmakiola.calendula.domain.EventInstance
 import de.jeanlucmakiola.calendula.domain.EventStatus
 import de.jeanlucmakiola.calendula.domain.RecurringWriteScope
 import de.jeanlucmakiola.calendula.domain.Reminder
+import de.jeanlucmakiola.calendula.ui.common.predictiveBack
 import de.jeanlucmakiola.calendula.ui.common.CalendarFailure
 import de.jeanlucmakiola.calendula.ui.common.OptionCard
 import de.jeanlucmakiola.calendula.ui.common.currentLocale
@@ -132,8 +132,6 @@ fun EventDetailScreen(
     val state by viewModel.state.collectAsStateWithLifecycle()
     val deleteState by viewModel.deleteState.collectAsStateWithLifecycle()
 
-    BackHandler(onBack = onBack)
-
     val context = LocalContext.current
     val scope = rememberCoroutineScope()
     val snackbarHostState = remember { SnackbarHostState() }
@@ -214,6 +212,7 @@ fun EventDetailScreen(
     }
 
     Scaffold(
+        modifier = Modifier.predictiveBack(onBack = onBack),
         snackbarHost = { SnackbarHost(snackbarHostState) },
         topBar = {
             TopAppBar(

app/src/main/java/de/jeanlucmakiola/calendula/ui/edit/EventEditScreen.kt

@@ -8,14 +8,9 @@ import android.content.pm.PackageManager
 import android.net.Uri
 import android.provider.ContactsContract
 import android.util.Patterns
-import androidx.activity.compose.BackHandler
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.animation.expandVertically
-import androidx.compose.animation.fadeIn
-import androidx.compose.animation.fadeOut
-import androidx.compose.animation.shrinkVertically
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
 import androidx.compose.foundation.isSystemInDarkTheme
@@ -63,7 +58,6 @@ import androidx.compose.material3.DropdownMenu
 import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.FilterChip
-import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
@@ -121,6 +115,9 @@ import de.jeanlucmakiola.calendula.domain.RecurringWriteScope
 import de.jeanlucmakiola.calendula.domain.SimpleRecurrence
 import de.jeanlucmakiola.calendula.domain.parseSimpleRecurrence
 import de.jeanlucmakiola.calendula.domain.toRRule
+import de.jeanlucmakiola.calendula.ui.common.calendarCollapseExit
+import de.jeanlucmakiola.calendula.ui.common.calendarExpandEnter
+import de.jeanlucmakiola.calendula.ui.common.predictiveBack
 import de.jeanlucmakiola.calendula.ui.common.CALENDAR_COLOR_PALETTE
 import de.jeanlucmakiola.calendula.ui.common.CalendarDatePickerDialog
 import de.jeanlucmakiola.calendula.ui.common.ColorSwatchRow
@@ -202,8 +199,6 @@ fun EventEditScreen(
         viewModel.reset()
         onClose()
     }
-    BackHandler(onBack = close)
-
     // The event vanished between the detail screen and the edit tap — fall
     // back to the detail screen, which shows its own failure state.
     LaunchedEffect(loadFailed) {
@@ -253,6 +248,7 @@ fun EventEditScreen(
     }
 
     Scaffold(
+        modifier = Modifier.predictiveBack(onBack = close),
         snackbarHost = { SnackbarHost(snackbarHostState) },
         topBar = {
             TopAppBar(
@@ -410,7 +406,6 @@ private enum class PickerTarget { StartDate, StartTime, EndDate, EndTime }
  * spring open with the expressive spatial spec instead of popping in.
  * (Initially-visible sections render without animating.)
  */
-@OptIn(ExperimentalMaterial3ExpressiveApi::class)
 @Composable
 private fun OptionalFormSection(
     visible: Boolean,
@@ -418,10 +413,8 @@ private fun OptionalFormSection(
 ) {
     AnimatedVisibility(
         visible = visible,
-        enter = expandVertically(MaterialTheme.motionScheme.fastSpatialSpec()) +
+        enter = calendarExpandEnter(),
-            fadeIn(MaterialTheme.motionScheme.fastEffectsSpec()),
+        exit = calendarCollapseExit(),
-        exit = shrinkVertically(MaterialTheme.motionScheme.fastSpatialSpec()) +
-            fadeOut(MaterialTheme.motionScheme.fastEffectsSpec()),
     ) {
         Column(modifier = Modifier.fillMaxWidth(), content = content)
     }

app/src/main/java/de/jeanlucmakiola/calendula/ui/imports/ImportScreen.kt

@@ -1,7 +1,6 @@
 package de.jeanlucmakiola.calendula.ui.imports
 
 import android.net.Uri
-import androidx.activity.compose.BackHandler
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -39,6 +38,7 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventForm
 import de.jeanlucmakiola.calendula.domain.ics.IcsParseWarning
+import de.jeanlucmakiola.calendula.ui.common.predictiveBack
 import de.jeanlucmakiola.calendula.ui.common.OptionCard
 
 /**
@@ -57,7 +57,6 @@ fun ImportScreen(
 ) {
     LaunchedEffect(uri) { viewModel.load(uri) }
     val state by viewModel.state.collectAsStateWithLifecycle()
-    BackHandler(onBack = onClose)
 
     // A single event isn't shown here — it opens the create form for review.
     LaunchedEffect(state) {
@@ -65,7 +64,9 @@ fun ImportScreen(
     }
 
     Scaffold(
-        modifier = Modifier.fillMaxSize(),
+        modifier = Modifier
+            .predictiveBack(onBack = onClose)
+            .fillMaxSize(),
         topBar = {
             TopAppBar(
                 title = { Text(stringResource(R.string.import_title)) },

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

@@ -66,6 +66,8 @@ import de.jeanlucmakiola.calendula.ui.common.CalendarFailure
 import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.ViewSwitcherPill
 import de.jeanlucmakiola.calendula.ui.common.calendarSlideTransition
+import de.jeanlucmakiola.calendula.ui.common.rememberCalendarFadeSpec
+import de.jeanlucmakiola.calendula.ui.common.rememberReduceMotion
 import de.jeanlucmakiola.calendula.ui.common.currentLocale
 import de.jeanlucmakiola.calendula.ui.common.rememberCalendarSlideSpec
 import de.jeanlucmakiola.calendula.ui.common.next
@@ -217,6 +219,8 @@ private fun MonthContent(
     val threshold = with(density) { 6.dp.toPx() }
     var dragAccum by remember { mutableFloatStateOf(0f) }
     val slideSpec = rememberCalendarSlideSpec()
+    val fadeSpec = rememberCalendarFadeSpec()
+    val reduceMotion = rememberReduceMotion()
 
     val swipeModifier = Modifier.pointerInput(Unit) {
         detectHorizontalDragGestures(
@@ -243,7 +247,7 @@ private fun MonthContent(
                 MonthUiState.Loading -> "loading"
             }
         },
-        transitionSpec = { calendarSlideTransition(slideDir, slideSpec) },
+        transitionSpec = { calendarSlideTransition(slideDir, slideSpec, fadeSpec, reduceMotion) },
         label = "month-transition",
     ) { s ->
         when (s) {

app/src/main/java/de/jeanlucmakiola/calendula/ui/search/SearchScreen.kt

@@ -1,6 +1,5 @@
 package de.jeanlucmakiola.calendula.ui.search
 
-import androidx.activity.compose.BackHandler
 import androidx.compose.foundation.background
 import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.Arrangement
@@ -49,6 +48,8 @@ import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.common.calendarAnimateItem
+import de.jeanlucmakiola.calendula.ui.common.predictiveBack
 import de.jeanlucmakiola.calendula.ui.common.GroupedRow
 import de.jeanlucmakiola.calendula.ui.common.InlineTextField
 import de.jeanlucmakiola.calendula.ui.common.Position
@@ -88,10 +89,8 @@ fun SearchScreen(
         focusRequester.requestFocus()
         keyboard?.show()
     }
-    BackHandler(onBack = onBack)
-
     Scaffold(
-        modifier = modifier,
+        modifier = modifier.predictiveBack(onBack = onBack),
         containerColor = MaterialTheme.colorScheme.surface,
         topBar = {
             TopAppBar(
@@ -174,6 +173,7 @@ private fun SearchResults(
             SearchResultRow(
                 event = event,
                 position = positionOf(index, events.size),
+                modifier = calendarAnimateItem(),
                 onClick = { onEventClick(event) },
             )
         }
@@ -184,10 +184,12 @@ private fun SearchResults(
 private fun SearchResultRow(
     event: EventInstance,
     position: Position,
+    modifier: Modifier = Modifier,
     onClick: () -> Unit,
 ) {
     val dark = isSystemInDarkTheme()
     GroupedRow(
+        modifier = modifier,
         title = event.title,
         summary = searchSummary(event),
         position = position,

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsScreen.kt

@@ -88,8 +88,12 @@ import de.jeanlucmakiola.calendula.qs.NewEventTileService
 import de.jeanlucmakiola.calendula.ui.crash.CrashReportDialog
 import de.jeanlucmakiola.calendula.ui.crash.openIssueTracker
 import de.jeanlucmakiola.calendula.ui.crash.submitCrashReport
+import de.jeanlucmakiola.calendula.ui.common.calendarCollapseExit
+import de.jeanlucmakiola.calendula.ui.common.calendarExpandEnter
 import de.jeanlucmakiola.calendula.ui.common.CollapsingScaffold
 import de.jeanlucmakiola.calendula.ui.common.GroupedRow
+import de.jeanlucmakiola.calendula.ui.common.IMPLEMENTED_VIEWS
+import de.jeanlucmakiola.calendula.ui.common.labelRes
 import de.jeanlucmakiola.calendula.ui.common.CalendarColorChip
 import de.jeanlucmakiola.calendula.ui.common.OptionPicker
 import de.jeanlucmakiola.calendula.ui.common.Position
@@ -404,6 +408,7 @@ private fun AppearanceScreen(
 ) {
     var showTheme by remember { mutableStateOf(false) }
     var showWeekStart by remember { mutableStateOf(false) }
+    var showDefaultView by remember { mutableStateOf(false) }
 
     CollapsingScaffold(
         title = stringResource(R.string.settings_section_appearance),
@@ -415,6 +420,12 @@ private fun AppearanceScreen(
             position = Position.Top,
             onClick = { showTheme = true },
         )
+        GroupedRow(
+            title = stringResource(R.string.settings_default_view),
+            summary = stringResource(state.defaultView.labelRes),
+            position = Position.Middle,
+            onClick = { showDefaultView = true },
+        )
         GroupedRow(
             title = stringResource(R.string.settings_dynamic_color),
             summary = if (state.dynamicColorAvailable) {
@@ -464,6 +475,16 @@ private fun AppearanceScreen(
             onDismiss = { showWeekStart = false },
         )
     }
+    if (showDefaultView) {
+        OptionPicker(
+            title = stringResource(R.string.settings_default_view),
+            options = IMPLEMENTED_VIEWS,
+            selected = state.defaultView,
+            label = { stringResource(it.labelRes) },
+            onSelect = viewModel::setDefaultView,
+            onDismiss = { showDefaultView = false },
+        )
+    }
 }
 
 @Composable
@@ -655,7 +676,11 @@ private fun NotificationsScreen(
                         }
                     },
                 )
-                AnimatedVisibility(visible = expanded) {
+                AnimatedVisibility(
+                    visible = expanded,
+                    enter = calendarExpandEnter(),
+                    exit = calendarCollapseExit(),
+                ) {
                     Column {
                         val timed = state.perCalendarReminderOverride.choiceFor(calendar.id)
                         GroupedRow(

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsUiState.kt

@@ -5,6 +5,7 @@ import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventFormField
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 
 /**
  * Settings screen state (M4). Persisted preferences are instant to read, so
@@ -17,6 +18,8 @@ data class SettingsUiState(
     val dynamicColor: Boolean = true,
     val dynamicColorAvailable: Boolean = true,
     val weekStart: WeekStartPref = WeekStartPref.AUTO,
+    /** The calendar view the app opens on, and the home of the view back stack (M1). */
+    val defaultView: CalendarView = CalendarView.Week,
     /** Optional event-form fields shown by default (rest behind "more fields"). */
     val defaultFormFields: Set<EventFormField> = SettingsPrefs.DEFAULT_FORM_FIELDS,
     /** Whether Calendula posts reminder notifications (v1.4). */

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsViewModel.kt

@@ -11,6 +11,7 @@ import de.jeanlucmakiola.calendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.calendula.data.prefs.WeekStartPref
 import de.jeanlucmakiola.calendula.domain.CalendarSource
 import de.jeanlucmakiola.calendula.domain.EventFormField
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.StateFlow
@@ -72,8 +73,10 @@ class SettingsViewModel @Inject constructor(
             ) { overrides, allDayOverrides, calendars ->
                 ReminderOverrides(overrides, allDayOverrides, calendars)
             },
-        ) { base, defaults, overrides ->
+            prefs.defaultView,
+        ) { base, defaults, overrides, defaultView ->
             base.copy(
+                defaultView = defaultView,
                 allowColorOnUnsupportedCalendars = defaults.allowColor,
                 defaultReminderMinutes = defaults.defaultReminder,
                 defaultAllDayReminderMinutes = defaults.allDayReminder,
@@ -115,6 +118,10 @@ class SettingsViewModel @Inject constructor(
         viewModelScope.launch { prefs.setWeekStart(pref) }
     }
 
+    fun setDefaultView(view: CalendarView) {
+        viewModelScope.launch { prefs.setDefaultView(view) }
+    }
+
     fun setFormFieldDefault(field: EventFormField, enabled: Boolean) {
         viewModelScope.launch { prefs.setFormFieldDefault(field, enabled) }
     }

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

@@ -80,6 +80,8 @@ import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.NowLine
 import de.jeanlucmakiola.calendula.ui.common.ViewSwitcherPill
 import de.jeanlucmakiola.calendula.ui.common.calendarSlideTransition
+import de.jeanlucmakiola.calendula.ui.common.rememberCalendarFadeSpec
+import de.jeanlucmakiola.calendula.ui.common.rememberReduceMotion
 import de.jeanlucmakiola.calendula.ui.common.currentLocale
 import de.jeanlucmakiola.calendula.ui.common.rememberCalendarSlideSpec
 import de.jeanlucmakiola.calendula.ui.common.next
@@ -247,6 +249,8 @@ private fun WeekContent(
     val threshold = with(density) { 24.dp.toPx() }
     var dragAccum by remember { mutableFloatStateOf(0f) }
     val slideSpec = rememberCalendarSlideSpec()
+    val fadeSpec = rememberCalendarFadeSpec()
+    val reduceMotion = rememberReduceMotion()
 
     // Hoisted above the per-week AnimatedContent so the vertical scroll position
     // survives week-to-week swipes (e.g. 18:00 stays centred). We only centre on
@@ -300,7 +304,7 @@ private fun WeekContent(
                 WeekUiState.Loading -> "loading"
             }
         },
-        transitionSpec = { calendarSlideTransition(slideDir, slideSpec) },
+        transitionSpec = { calendarSlideTransition(slideDir, slideSpec, fadeSpec, reduceMotion) },
         label = "week-transition",
     ) { s ->
         when (s) {

app/src/main/java/de/jeanlucmakiola/calendula/widget/agenda/AgendaWidget.kt

@@ -41,6 +41,7 @@ import androidx.glance.text.TextStyle
 import de.jeanlucmakiola.calendula.MainActivity
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.pastelize
 import de.jeanlucmakiola.calendula.widget.AgendaWidgetData
 import de.jeanlucmakiola.calendula.widget.CalendulaGlanceTheme
@@ -185,7 +186,11 @@ private fun DayHeaderRow(date: LocalDate, today: LocalDate) {
         modifier = GlanceModifier
             .fillMaxWidth()
             .padding(start = 8.dp, end = 8.dp, top = 10.dp, bottom = 4.dp)
-            .clickable(actionStartActivity(MainActivity.openDateIntent(context, date))),
+            .clickable(
+                actionStartActivity(
+                    MainActivity.openDateIntent(context, date, CalendarView.Agenda),
+                ),
+            ),
     )
 }
 
@@ -199,11 +204,12 @@ private fun EventRow(event: EventInstance, dark: Boolean) {
             .padding(horizontal = 4.dp, vertical = 4.dp)
             .clickable(
                 actionStartActivity(
-                    MainActivity.eventDetailIntent(
+                    MainActivity.openEventIntent(
                         context = context,
                         eventId = event.eventId,
                         beginMillis = event.start.toEpochMilliseconds(),
                         endMillis = event.end.toEpochMilliseconds(),
+                        source = CalendarView.Agenda,
                     ),
                 ),
             ),

app/src/main/java/de/jeanlucmakiola/calendula/widget/month/MonthWidget.kt

@@ -49,6 +49,7 @@ import androidx.glance.unit.ColorProvider
 import de.jeanlucmakiola.calendula.MainActivity
 import de.jeanlucmakiola.calendula.R
 import de.jeanlucmakiola.calendula.domain.EventInstance
+import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.pastelize
 import de.jeanlucmakiola.calendula.ui.month.MonthWeek
 import de.jeanlucmakiola.calendula.ui.month.layoutMonthWeeks
@@ -209,7 +210,9 @@ private fun MonthHeader(label: String) {
             resId = R.drawable.ic_widget_today,
             contentDescription = context.getString(R.string.widget_today),
             onClick = GlanceModifier.clickable(
-                actionStartActivity(MainActivity.openDateIntent(context, today(systemZone()))),
+                actionStartActivity(
+                    MainActivity.openDateIntent(context, today(systemZone()), CalendarView.Month),
+                ),
             ),
         )
         HeaderIcon(
@@ -300,8 +303,16 @@ private fun WeekRow(
 
 @Composable
 private fun DayNumber(date: LocalDate, isToday: Boolean, inMonth: Boolean, colW: Dp) {
+    val context = LocalContext.current
     Box(
-        modifier = GlanceModifier.width(colW).height(DAY_NUMBER_HEIGHT),
+        modifier = GlanceModifier
+            .width(colW)
+            .height(DAY_NUMBER_HEIGHT)
+            // Tap a day number to open that day, rooted in the month view so back
+            // returns to the month grid.
+            .clickable(
+                actionStartActivity(MainActivity.openDateIntent(context, date, CalendarView.Month)),
+            ),
         contentAlignment = Alignment.Center,
     ) {
         Box(
@@ -353,7 +364,24 @@ private fun LaneRow(week: MonthWeek, lane: Int, dark: Boolean, colW: Dp) {
 @Composable
 private fun SpanBar(event: EventInstance, dark: Boolean, width: Dp) {
     val context = LocalContext.current
-    Box(modifier = GlanceModifier.width(width).height(LANE_HEIGHT).padding(horizontal = 1.dp)) {
+    Box(
+        modifier = GlanceModifier
+            .width(width)
+            .height(LANE_HEIGHT)
+            .padding(horizontal = 1.dp)
+            // Tap an event bar to open its detail, rooted in the month view.
+            .clickable(
+                actionStartActivity(
+                    MainActivity.openEventIntent(
+                        context = context,
+                        eventId = event.eventId,
+                        beginMillis = event.start.toEpochMilliseconds(),
+                        endMillis = event.end.toEpochMilliseconds(),
+                        source = CalendarView.Month,
+                    ),
+                ),
+            ),
+    ) {
         Box(
             modifier = GlanceModifier
                 .fillMaxSize()

app/src/main/res/values/strings.xml

@@ -264,6 +264,7 @@
     <string name="settings_theme_system">System</string>
     <string name="settings_theme_light">Light</string>
     <string name="settings_theme_dark">Dark</string>
+    <string name="settings_default_view">Default view</string>
     <string name="settings_dynamic_color">Dynamic colour</string>
     <string name="settings_dynamic_color_unavailable">Requires Android 12 or newer</string>
     <string name="settings_week_start">Week starts on</string>
@@ -299,7 +300,7 @@
     <string name="settings_language">App language</string>
     <string name="settings_language_auto">System default</string>
     <!-- Hub category subtitles -->
-    <string name="settings_appearance_subtitle">Theme, dynamic colour, week start</string>
+    <string name="settings_appearance_subtitle">Theme, default view, week start</string>
     <string name="settings_event_form_subtitle">Default fields for new events</string>
     <string name="settings_notifications_subtitle">Event reminders</string>
     <string name="settings_section_about">About</string>

app/src/test/java/de/jeanlucmakiola/calendula/ui/common/ViewBackStackTest.kt

@@ -0,0 +1,94 @@
+package de.jeanlucmakiola.calendula.ui.common
+
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+
+/**
+ * The pure back-stack rules behind [CalendarHost]'s top-level navigation:
+ * the home view is always the bottom, a lateral move keeps the stack one deep,
+ * and a date tap drills the day view on top. Verifies the back sequences the
+ * widget-UX fix promises (e.g. agenda widget → day → back → agenda → back → home).
+ */
+class ViewBackStackTest {
+
+    @Test
+    fun `a widget whose view is the home view resets to just the home`() {
+        assertThat(viewBaseStack(CalendarView.Week, CalendarView.Week))
+            .containsExactly(CalendarView.Week)
+    }
+
+    @Test
+    fun `a widget launch resets to its view over the home`() {
+        assertThat(viewBaseStack(CalendarView.Week, CalendarView.Month))
+            .containsExactly(CalendarView.Week, CalendarView.Month)
+            .inOrder()
+    }
+
+    @Test
+    fun `pill switches build a visit history that back retraces`() {
+        // Agenda → Day → Week → Month, each a new view, stacks the full history.
+        val stack = listOf(CalendarView.Agenda)
+            .selectView(CalendarView.Day)
+            .selectView(CalendarView.Week)
+            .selectView(CalendarView.Month)
+        assertThat(stack).containsExactly(
+            CalendarView.Agenda, CalendarView.Day, CalendarView.Week, CalendarView.Month,
+        ).inOrder()
+        // Back walks the views in reverse, not straight to the home view.
+        assertThat(stack.dropLast(1).last()).isEqualTo(CalendarView.Week)
+    }
+
+    @Test
+    fun `selecting an already-visited view collapses the loop back to it`() {
+        val stack = listOf(CalendarView.Week, CalendarView.Agenda, CalendarView.Day)
+            .selectView(CalendarView.Agenda)
+        assertThat(stack).containsExactly(CalendarView.Week, CalendarView.Agenda).inOrder()
+    }
+
+    @Test
+    fun `selecting the home view collapses to just the home`() {
+        val stack = listOf(CalendarView.Week, CalendarView.Agenda, CalendarView.Day)
+            .selectView(CalendarView.Week)
+        assertThat(stack).containsExactly(CalendarView.Week)
+    }
+
+    @Test
+    fun `drilling pushes the day view on top`() {
+        assertThat(listOf(CalendarView.Week, CalendarView.Month).drillToDay())
+            .containsExactly(CalendarView.Week, CalendarView.Month, CalendarView.Day)
+            .inOrder()
+    }
+
+    @Test
+    fun `drilling is a no-op when the day view is already current`() {
+        val stack = listOf(CalendarView.Week, CalendarView.Day)
+        assertThat(stack.drillToDay()).isEqualTo(stack)
+    }
+
+    @Test
+    fun `agenda widget date tap backs out agenda then home`() {
+        // openDate(source = Agenda): root in Agenda over the Week home, then drill.
+        val stack = viewBaseStack(CalendarView.Week, CalendarView.Agenda).drillToDay()
+        assertThat(stack)
+            .containsExactly(CalendarView.Week, CalendarView.Agenda, CalendarView.Day)
+            .inOrder()
+        // Pressing back pops one level at a time down to the home view.
+        assertThat(stack.dropLast(1)).containsExactly(CalendarView.Week, CalendarView.Agenda).inOrder()
+        assertThat(stack.dropLast(2)).containsExactly(CalendarView.Week)
+    }
+
+    @Test
+    fun `month widget date tap backs out month then home`() {
+        val stack = viewBaseStack(CalendarView.Week, CalendarView.Month).drillToDay()
+        assertThat(stack.last()).isEqualTo(CalendarView.Day)
+        assertThat(stack.dropLast(1).last()).isEqualTo(CalendarView.Month)
+        assertThat(stack.first()).isEqualTo(CalendarView.Week)
+    }
+
+    @Test
+    fun `a widget whose view is the home view does not duplicate the home`() {
+        // Default = Agenda, agenda widget event tap → just the home, no extra layer.
+        assertThat(viewBaseStack(CalendarView.Agenda, CalendarView.Agenda))
+            .containsExactly(CalendarView.Agenda)
+    }
+}

fastlane/metadata/android/en-US/changelogs/20900.txt

@@ -0,0 +1,33 @@
+### Added
+- Choose the view Calendula opens on. A new **Default view** setting (Settings →
+  Appearance) lets you pick Month, Week, Day or Agenda as the view shown each
+  time you start the app, instead of always opening on Week. Thanks to
+  @devinside for the suggestion ([#1]).
+- The month widget is now interactive: tap any day to open it, or tap an event to
+  open its details. Previously only the month's prev/next/today controls
+  responded. Thanks to @devinside for spotting this ([#2]).
+- Predictive back. Swiping back from a screen — an event, the editor, search or
+  settings — now follows your finger, shrinking the screen to preview what's
+  behind so you can see where Back will take you before you let go; slide it back
+  to cancel. The preview needs Android 14 or newer; on older versions Back works
+  as before.
+- Respect for "Remove animations". If you've turned animations off in your
+  device's Accessibility settings, Calendula now honours it everywhere: motion
+  collapses to a quick fade and the back preview is skipped.
+
+### Changed
+- Smoother, more consistent motion throughout. Expanding sections, list updates
+  in search and agenda, and the onboarding screens now animate the same way
+  across the app, instead of some places sliding or growing while others popped
+  in. Switching between Month, Week, Day and Agenda now cross-fades rather than
+  snapping, while paging within a view keeps its slide.
+
+### Fixed
+- Home-screen widgets now back out the way you came in. A day or event opened
+  from the Agenda widget keeps you in the agenda context, and from the Month
+  widget in the month context — pressing Back returns there instead of dropping
+  you on the week view. More broadly, the app now keeps a real view history:
+  switching views and drilling into a day are retraced by Back one step at a
+  time, down to your default view before the app exits. Thanks to @devinside for
+  reporting ([#2]).
+