Handle null-safety error in FeedDao

The lastUpdated parameter can be null, adjust return types to signal that too

Signed-off-by: Aayush Gupta <[email protected]>

Author: theimpulson

app/src/main/java/org/schabi/newpipe/database/feed/dao/FeedDAO.kt

@@ -168,10 +168,10 @@ abstract class FeedDAO {
         ON fgs.subscription_id = lu.subscription_id AND fgs.group_id = :groupId
         """
     )
-    abstract fun oldestSubscriptionUpdate(groupId: Long): Flowable<List<OffsetDateTime>>
+    abstract fun oldestSubscriptionUpdate(groupId: Long): Flowable<List<OffsetDateTime?>>
 
     @Query("SELECT MIN(last_updated) FROM feed_last_updated")
-    abstract fun oldestSubscriptionUpdateFromAll(): Flowable<List<OffsetDateTime>>
+    abstract fun oldestSubscriptionUpdateFromAll(): Flowable<List<OffsetDateTime?>>
 
     @Query("SELECT COUNT(*) FROM feed_last_updated WHERE last_updated IS NULL")
     abstract fun notLoadedCount(): Flowable<Long>

app/src/main/java/org/schabi/newpipe/local/feed/FeedDatabaseManager.kt

@@ -177,7 +177,7 @@ class FeedDatabaseManager(context: Context) {
             .observeOn(AndroidSchedulers.mainThread())
     }
 
-    fun oldestSubscriptionUpdate(groupId: Long): Flowable<List<OffsetDateTime>> {
+    fun oldestSubscriptionUpdate(groupId: Long): Flowable<List<OffsetDateTime?>> {
         return when (groupId) {
             FeedGroupEntity.GROUP_ALL_ID -> feedTable.oldestSubscriptionUpdateFromAll()
             else -> feedTable.oldestSubscriptionUpdate(groupId)

app/src/main/java/org/schabi/newpipe/local/feed/FeedViewModel.kt

@@ -65,7 +65,7 @@ class FeedViewModel(
             feedDatabaseManager.oldestSubscriptionUpdate(groupId),
 
             Function6 { t1: FeedEventManager.Event, t2: Boolean, t3: Boolean, t4: Boolean,
-                t5: Long, t6: List<OffsetDateTime> ->
+                t5: Long, t6: List<OffsetDateTime?> ->
                 return@Function6 CombineResultEventHolder(t1, t2, t3, t4, t5, t6.firstOrNull())
             }
         )