app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/CalendarDataSource.kt

@@ -492,7 +492,13 @@ class AndroidCalendarDataSource @Inject constructor(
         return resolver.query(
             uri,
             InstanceProjection.COLUMNS,
-            null, null,
+            // Hide cancelled occurrences: "delete only this event" writes a
+            // cancelled exception for the one instance (#47). A NULL status is a
+            // normal, un-cancelled event, so it must survive the filter — a bare
+            // `!= CANCELED` would drop it (NULL != 2 is NULL, not true).
+            "${CalendarContract.Instances.STATUS} IS NULL OR " +
+                "${CalendarContract.Instances.STATUS} != ${CalendarContract.Events.STATUS_CANCELED}",
+            null,
             CalendarContract.Instances.BEGIN + " ASC",
         )?.use { c -> c.mapAllNotNull { CursorColumnReader(c).toEventInstance() } } ?: emptyList()
     }
@@ -1183,15 +1189,25 @@ class AndroidCalendarDataSource @Inject constructor(
 
     override fun deleteOccurrence(eventId: Long, beginMillis: Long) {
         // A cancelled exception row hides exactly this occurrence; the sync
-        // adapter turns it into an EXDATE/cancelled VEVENT upstream.
+        // adapter turns it into an EXDATE/cancelled VEVENT upstream. It has to
-        val values = ContentValues().apply {
+        // carry the full time set (DTSTART + DURATION + zone), not just STATUS:
-            put(CalendarContract.Events.ORIGINAL_INSTANCE_TIME, beginMillis)
+        // the provider only demotes the cloned exception to a single instance —
-            put(CalendarContract.Events.STATUS, CalendarContract.Events.STATUS_CANCELED)
+        // clearing the inherited RRULE — when it can derive that instance from
-        }
+        // those columns. A STATUS-only cancel left the RRULE standing and
+        // cancelled the whole series, wiping every other occurrence (#47), the
+        // same trap the edit path documents (Codeberg #16).
+        val row = querySeriesRow(eventId)
+        val values = buildOccurrenceCancelValues(
+            originalInstanceMillis = beginMillis,
+            dtStartMillis = beginMillis,
+            duration = row.duration,
+            timezone = row.timezone,
+            allDay = row.allDay,
+        )
         val uri = ContentUris.withAppendedId(
             CalendarContract.Events.CONTENT_EXCEPTION_URI, eventId,
         )
-        resolver.insert(uri, values)
+        resolver.insert(uri, values.toContentValues())
             ?: throw WriteFailedException("cancel occurrence event id=$eventId begin=$beginMillis")
     }
 

app/src/main/java/de/jeanlucmakiola/calendula/data/calendar/EventWriteMapper.kt

@@ -182,6 +182,33 @@ internal fun buildOccurrenceExceptionValues(
     putAll(eventColorColumns(form.colorKey, form.color))
 }
 
+/**
+ * Column values for a *cancelled*-occurrence exception row ("delete only this
+ * event"): inserting them at `Events.CONTENT_EXCEPTION_URI/<id>` makes the
+ * provider clone the series row and cancel exactly this one instance.
+ *
+ * As with [buildOccurrenceExceptionValues], the occurrence must be anchored with
+ * DTSTART + DURATION so the provider derives a single instance and clears the
+ * inherited RRULE. A STATUS-only cancel skips that: the clone keeps the RRULE, so
+ * the *whole series* is cancelled and every other occurrence disappears
+ * (Codeberg #47). The occurrence's length/zone come straight from the series row
+ * — cancelling never changes them.
+ */
+internal fun buildOccurrenceCancelValues(
+    originalInstanceMillis: Long,
+    dtStartMillis: Long,
+    duration: String?,
+    timezone: String?,
+    allDay: Int,
+): Map<String, Any?> = buildMap {
+    put(CalendarContract.Events.ORIGINAL_INSTANCE_TIME, originalInstanceMillis)
+    put(CalendarContract.Events.DTSTART, dtStartMillis)
+    put(CalendarContract.Events.DURATION, duration)
+    put(CalendarContract.Events.EVENT_TIMEZONE, timezone)
+    put(CalendarContract.Events.ALL_DAY, allDay)
+    put(CalendarContract.Events.STATUS, CalendarContract.Events.STATUS_CANCELED)
+}
+
 /**
  * The `EVENT_COLOR` / `EVENT_COLOR_KEY` columns for a colour selection. A
  * [colorKey] writes the key alone (the provider derives `EVENT_COLOR` from the

app/src/test/java/de/jeanlucmakiola/calendula/data/calendar/EventWriteMapperTest.kt

@@ -220,6 +220,46 @@ class EventWriteMapperTest {
         assertThat(values).containsEntry(CalendarContract.Events.DESCRIPTION, null)
     }
 
+    // --- buildOccurrenceCancelValues ("delete only this event") ---
+
+    @Test
+    fun `occurrence cancel anchors a single instance and cancels only it`() {
+        val values = buildOccurrenceCancelValues(
+            originalInstanceMillis = 1_700_000_000_000L,
+            dtStartMillis = 1_700_000_000_000L,
+            duration = "P3600S",
+            timezone = "Europe/Berlin",
+            allDay = 0,
+        )
+        assertThat(values[CalendarContract.Events.ORIGINAL_INSTANCE_TIME])
+            .isEqualTo(1_700_000_000_000L)
+        // DTSTART + DURATION make the provider derive a single instance and drop
+        // the inherited RRULE, so only this occurrence is cancelled — not the
+        // whole series (#47). DTEND is never sent (the provider rejects it).
+        assertThat(values[CalendarContract.Events.DTSTART]).isEqualTo(1_700_000_000_000L)
+        assertThat(values[CalendarContract.Events.DURATION]).isEqualTo("P3600S")
+        assertThat(values[CalendarContract.Events.EVENT_TIMEZONE]).isEqualTo("Europe/Berlin")
+        assertThat(values[CalendarContract.Events.STATUS])
+            .isEqualTo(CalendarContract.Events.STATUS_CANCELED)
+        assertThat(values).doesNotContainKey(CalendarContract.Events.DTEND)
+        assertThat(values).doesNotContainKey(CalendarContract.Events.RRULE)
+    }
+
+    @Test
+    fun `all-day occurrence cancel keeps the all-day flag and utc zone`() {
+        val values = buildOccurrenceCancelValues(
+            originalInstanceMillis = 1_700_000_000_000L,
+            dtStartMillis = 1_700_000_000_000L,
+            duration = "P1D",
+            timezone = "UTC",
+            allDay = 1,
+        )
+        assertThat(values[CalendarContract.Events.ALL_DAY]).isEqualTo(1)
+        assertThat(values[CalendarContract.Events.EVENT_TIMEZONE]).isEqualTo("UTC")
+        assertThat(values[CalendarContract.Events.STATUS])
+            .isEqualTo(CalendarContract.Events.STATUS_CANCELED)
+    }
+
     // --- per-event colour ---
 
     @Test