delete conversation cache on logout (#1037)

* delete conversation cache on logout

* use correct threading method

app/src/main/java/com/keylesspalace/tusky/MainActivity.java

@@ -40,6 +40,7 @@ import com.keylesspalace.tusky.appstore.CacheUpdater;
 import com.keylesspalace.tusky.appstore.EventHub;
 import com.keylesspalace.tusky.appstore.MainTabsChangedEvent;
 import com.keylesspalace.tusky.appstore.ProfileEditedEvent;
+import com.keylesspalace.tusky.components.conversation.ConversationsRepository;
 import com.keylesspalace.tusky.db.AccountEntity;
 import com.keylesspalace.tusky.entity.Account;
 import com.keylesspalace.tusky.interfaces.ActionButtonActivity;
@@ -103,6 +104,8 @@ public final class MainActivity extends BottomSheetActivity implements ActionBut
     public EventHub eventHub;
     @Inject
     public CacheUpdater cacheUpdater;
+    @Inject
+    ConversationsRepository conversationRepository;
 
     private FloatingActionButton composeButton;
     private AccountHeader headerResult;
@@ -472,6 +475,7 @@ public final class MainActivity extends BottomSheetActivity implements ActionBut
 
                         NotificationHelper.deleteNotificationChannelsForAccount(accountManager.getActiveAccount(), MainActivity.this);
                         cacheUpdater.clearForUser(activeAccount.getId());
+                        conversationRepository.deleteCacheForAccount(activeAccount.getId());
 
                         AccountEntity newAccount = accountManager.logActiveAccountOut();
 

app/src/main/java/com/keylesspalace/tusky/components/conversation/ConversationsRepository.kt

@@ -11,6 +11,8 @@ import com.keylesspalace.tusky.entity.Conversation
 import com.keylesspalace.tusky.network.MastodonApi
 import com.keylesspalace.tusky.util.Listing
 import com.keylesspalace.tusky.util.NetworkState
+import io.reactivex.Single
+import io.reactivex.schedulers.Schedulers
 import retrofit2.Call
 import retrofit2.Callback
 import retrofit2.Response
@@ -93,6 +95,13 @@ class ConversationsRepository @Inject constructor(val mastodonApi: MastodonApi,
         )
     }
 
+    fun deleteCacheForAccount(accountId: Long) {
+        Single.fromCallable {
+            db.conversationDao().deleteForAccount(accountId)
+        }.subscribeOn(Schedulers.io())
+                .subscribe()
+    }
+
     private fun insertResultIntoDb(accountId: Long, result: List<Conversation>?) {
         result?.let { conversations ->
             db.conversationDao().insert(conversations.map { it.toEntity(accountId) })