Resolves (or at least improves):

- #1538
- https://github.com/bitfireAT/davx5-ose/discussions/66
- https://github.com/Kozea/Radicale/issues/1264
- May also resolve some of the issues described in #1983.

The "EXDATE" property is only meant to be set on events with the "RRULE" property. See discussion in #1538, especially the response from DAVx5 support listed in the first comment.

I tried also setting STATUS_CANCELED on these recurrence exception events, but DAVx5 would sometimes no longer recognize them as belonging to the parent event and would give the child events different UIDs, which is undesirable. It seems like it works great to just leave out the EXDATE.

I have not tested this patch with other CalDAV setups, but it solves the problem for me on DAVx5+Radicale.

app/src/main/kotlin/com/simplemobiletools/calendar/pro/activities/EventActivity.kt

@@ -1310,7 +1310,7 @@ class EventActivity : SimpleActivity() {
         EditRepeatingEventDialog(this) {
             hideKeyboard()
             when (it) {
-                0 -> {
+                EDIT_SELECTED_OCCURRENCE -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepetitionException(mEvent.id!!, mEventOccurrenceTS, true)
                         mEvent.apply {
@@ -1326,7 +1326,7 @@ class EventActivity : SimpleActivity() {
                         }
                     }
                 }
-                1 -> {
+                EDIT_FUTURE_OCCURRENCES -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepeatLimit(mEvent.id!!, mEventOccurrenceTS)
                         mEvent.apply {
@@ -1338,8 +1338,7 @@ class EventActivity : SimpleActivity() {
                         }
                     }
                 }
-
-                2 -> {
+                EDIT_ALL_OCCURRENCES -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepeatLimit(mEvent.id!!, mEventOccurrenceTS)
                         eventsHelper.updateEvent(mEvent, updateAtCalDAV = true, showToasts = true) {

app/src/main/kotlin/com/simplemobiletools/calendar/pro/activities/TaskActivity.kt

@@ -464,7 +464,7 @@ class TaskActivity : SimpleActivity() {
         EditRepeatingEventDialog(this, isTask = true) {
             hideKeyboard()
             when (it) {
-                0 -> {
+                EDIT_SELECTED_OCCURRENCE -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepetitionException(mTask.id!!, mTaskOccurrenceTS, addToCalDAV = false)
                         mTask.apply {
@@ -480,7 +480,7 @@ class TaskActivity : SimpleActivity() {
                         }
                     }
                 }
-                1 -> {
+                EDIT_FUTURE_OCCURRENCES -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepeatLimit(mTask.id!!, mTaskOccurrenceTS)
                         mTask.apply {
@@ -492,7 +492,7 @@ class TaskActivity : SimpleActivity() {
                         }
                     }
                 }
-                2 -> {
+                EDIT_ALL_OCCURRENCES -> {
                     ensureBackgroundThread {
                         eventsHelper.addEventRepeatLimit(mTask.id!!, mTaskOccurrenceTS)
                         eventsHelper.updateEvent(mTask, updateAtCalDAV = false, showToasts = true) {

app/src/main/kotlin/com/simplemobiletools/calendar/pro/dialogs/EditRepeatingEventDialog.kt

@@ -4,6 +4,9 @@ import android.view.ViewGroup
 import androidx.appcompat.app.AlertDialog
 import com.simplemobiletools.calendar.pro.R
 import com.simplemobiletools.calendar.pro.activities.SimpleActivity
+import com.simplemobiletools.calendar.pro.helpers.EDIT_ALL_OCCURRENCES
+import com.simplemobiletools.calendar.pro.helpers.EDIT_FUTURE_OCCURRENCES
+import com.simplemobiletools.calendar.pro.helpers.EDIT_SELECTED_OCCURRENCE
 import com.simplemobiletools.commons.extensions.getAlertDialogBuilder
 import com.simplemobiletools.commons.extensions.hideKeyboard
 import com.simplemobiletools.commons.extensions.setupDialogStuff
@@ -14,9 +17,9 @@ class EditRepeatingEventDialog(val activity: SimpleActivity, val isTask: Boolean
 
     init {
         val view = (activity.layoutInflater.inflate(R.layout.dialog_edit_repeating_event, null) as ViewGroup).apply {
-            edit_repeating_event_one_only.setOnClickListener { sendResult(0) }
-            edit_repeating_event_this_and_future_occurences.setOnClickListener { sendResult(1) }
-            edit_repeating_event_all_occurrences.setOnClickListener { sendResult(2) }
+            edit_repeating_event_one_only.setOnClickListener { sendResult(EDIT_SELECTED_OCCURRENCE) }
+            edit_repeating_event_this_and_future_occurences.setOnClickListener { sendResult(EDIT_FUTURE_OCCURRENCES) }
+            edit_repeating_event_all_occurrences.setOnClickListener { sendResult(EDIT_ALL_OCCURRENCES) }
 
             if (isTask) {
                 edit_repeating_event_title.setText(R.string.task_is_repeatable)

app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/CalDAVHelper.kt

@@ -502,7 +502,6 @@ class CalDAVHelper(val context: Context) {
             put(Events.ORIGINAL_ID, event.getCalDAVEventId())
             put(Events.EVENT_TIMEZONE, TimeZone.getDefault().id.toString())
             put(Events.ORIGINAL_INSTANCE_TIME, occurrenceTS * 1000L)
-            put(Events.EXDATE, Formatter.getDayCodeFromTS(occurrenceTS))
         }
     }
 

app/src/main/kotlin/com/simplemobiletools/calendar/pro/helpers/Constants.kt

@@ -232,6 +232,10 @@ const val DELETE_SELECTED_OCCURRENCE = 0
 const val DELETE_FUTURE_OCCURRENCES = 1
 const val DELETE_ALL_OCCURRENCES = 2
 
+const val EDIT_SELECTED_OCCURRENCE = 0
+const val EDIT_FUTURE_OCCURRENCES = 1
+const val EDIT_ALL_OCCURRENCES = 2
+
 const val REMINDER_NOTIFICATION = 0
 const val REMINDER_EMAIL = 1