Move filter stuff to own ViewModel

8 files changed, 156 insertions, 138 deletions

diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainActivity.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainActivity.java
index cec0e3cef..c52ed0de1 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainActivity.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainActivity.java
@@ -82,6 +82,7 @@ import it.niedermann.nextcloud.deck.ui.card.EditActivity;
 import it.niedermann.nextcloud.deck.ui.exception.ExceptionDialogFragment;
 import it.niedermann.nextcloud.deck.ui.exception.ExceptionHandler;
 import it.niedermann.nextcloud.deck.ui.filter.FilterDialogFragment;
+import it.niedermann.nextcloud.deck.ui.filter.FilterViewModel;
 import it.niedermann.nextcloud.deck.ui.settings.SettingsActivity;
 import it.niedermann.nextcloud.deck.ui.stack.DeleteStackDialogFragment;
 import it.niedermann.nextcloud.deck.ui.stack.DeleteStackListener;
@@ -112,7 +113,8 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     protected ActivityMainBinding binding;
     protected NavHeaderMainBinding headerBinding;
 
-    private MainViewModel viewModel;
+    private MainViewModel mainViewModel;
+    private FilterViewModel filterViewModel;
 
     protected static final int ACTIVITY_ABOUT = 1;
     protected static final int ACTIVITY_SETTINGS = 2;
@@ -155,8 +157,9 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         headerBinding = NavHeaderMainBinding.bind(binding.navigationView.getHeaderView(0));
         setContentView(binding.getRoot());
 
-        viewModel = new ViewModelProvider(this).get(MainViewModel.class);
-        viewModel.getFilterInformation().observe(this, (info) -> invalidateOptionsMenu());
+        mainViewModel = new ViewModelProvider(this).get(MainViewModel.class);
+        filterViewModel = new ViewModelProvider(this).get(FilterViewModel.class);
+        filterViewModel.getFilterInformation().observe(this, (info) -> invalidateOptionsMenu());
 
         addList = getString(R.string.add_list);
         addBoard = getString(R.string.add_board);
@@ -200,7 +203,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                             registerAutoSyncOnNetworkAvailable();
                         } else {
-                            syncManager.synchronize(new IResponseCallback<Boolean>(viewModel.getCurrentAccount()) {
+                            syncManager.synchronize(new IResponseCallback<Boolean>(mainViewModel.getCurrentAccount()) {
                                 @Override
                                 public void onResponse(Boolean response) {
                                 }
@@ -234,7 +237,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
             CrossTabDragAndDrop<StackFragment, CardAdapter, FullCard> dragAndDrop = new CrossTabDragAndDrop<>(getResources());
             dragAndDrop.register(binding.viewPager, binding.stackTitles, getSupportFragmentManager());
             dragAndDrop.addItemMovedByDragListener((movedCard, stackId, position) -> {
-                syncManager.reorder(viewModel.getCurrentAccount().getId(), movedCard, stackId, position);
+                syncManager.reorder(mainViewModel.getCurrentAccount().getId(), movedCard, stackId, position);
                 DeckLog.info("Card \"" + movedCard.getCard().getTitle() + "\" was moved to Stack " + stackId + " on position " + position);
             });
 
@@ -250,7 +253,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                 if (this.boardsList.size() > 0) {
                     try {
                         Long stackId = stackAdapter.getItem(binding.viewPager.getCurrentItem()).getLocalId();
-                        startActivity(EditActivity.createNewCardIntent(this, viewModel.getCurrentAccount(), viewModel.getCurrentBoardLocalId(), stackId));
+                        startActivity(EditActivity.createNewCardIntent(this, mainViewModel.getCurrentAccount(), mainViewModel.getCurrentBoardLocalId(), stackId));
                     } catch (IndexOutOfBoundsException e) {
                         EditStackDialogFragment.newInstance(NO_STACK_ID).show(getSupportFragmentManager(), addList);
                     }
@@ -269,7 +272,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                     binding.viewPager.post(() -> {
                         // stackAdapter size might differ from position when an account has been deleted
                         if (stackAdapter.getItemCount() > position) {
-                            Application.saveCurrentStackId(getApplicationContext(), viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId(), stackAdapter.getItem(position).getLocalId());
+                            Application.saveCurrentStackId(getApplicationContext(), mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId(), stackAdapter.getItem(position).getLocalId());
                         } else {
                             DeckLog.logError(new IllegalStateException("Tried to save current Stack which cannot be available (stackAdapter doesn't have this position)"));
                         }
@@ -299,8 +302,8 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                         DeckLog.info("Do not clear Glide caches, because the user currently does not have a working internet connection");
                     }
                 } else DeckLog.warn("ConnectivityManager is null");
-                refreshCapabilities(viewModel.getCurrentAccount());
-                syncManager.synchronize(new IResponseCallback<Boolean>(viewModel.getCurrentAccount()) {
+                refreshCapabilities(mainViewModel.getCurrentAccount());
+                syncManager.synchronize(new IResponseCallback<Boolean>(mainViewModel.getCurrentAccount()) {
                     @Override
                     public void onResponse(Boolean response) {
                         runOnUiThread(() -> binding.swipeRefreshLayout.setRefreshing(false));
@@ -361,8 +364,8 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     @Override
     public void onCreateStack(String stackName) {
         // TODO this outer call is only necessary to get the highest order. Move logic to SyncManager.
-        observeOnce(syncManager.getStacksForBoard(viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId()), MainActivity.this, fullStacks -> {
-            final Stack s = new Stack(stackName, viewModel.getCurrentBoardLocalId());
+        observeOnce(syncManager.getStacksForBoard(mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId()), MainActivity.this, fullStacks -> {
+            final Stack s = new Stack(stackName, mainViewModel.getCurrentBoardLocalId());
             int heighestOrder = 0;
             for (FullStack fullStack : fullStacks) {
                 int currentStackOrder = fullStack.stack.getOrder();
@@ -371,8 +374,8 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                 }
             }
             s.setOrder(heighestOrder);
-            DeckLog.info("Create Stack in account " + viewModel.getCurrentAccount().getName() + " on board " + viewModel.getCurrentBoardLocalId());
-            WrappedLiveData<FullStack> createLiveData = syncManager.createStack(viewModel.getCurrentAccount().getId(), s);
+            DeckLog.info("Create Stack in account " + mainViewModel.getCurrentAccount().getName() + " on board " + mainViewModel.getCurrentBoardLocalId());
+            WrappedLiveData<FullStack> createLiveData = syncManager.createStack(mainViewModel.getCurrentAccount().getId(), s);
             observeOnce(createLiveData, this, (fullStack) -> {
                 if (createLiveData.hasError()) {
                     final Throwable error = createLiveData.getError();
@@ -387,7 +390,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
 
     @Override
     public void onUpdateStack(long localStackId, String stackName) {
-        observeOnce(syncManager.getStack(viewModel.getCurrentAccount().getId(), localStackId), MainActivity.this, fullStack -> {
+        observeOnce(syncManager.getStack(mainViewModel.getCurrentAccount().getId(), localStackId), MainActivity.this, fullStack -> {
             fullStack.getStack().setTitle(stackName);
             // TODO error handling
             syncManager.updateStack(fullStack);
@@ -403,7 +406,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         final Board boardToCreate = new Board(title, color.startsWith("#") ? color.substring(1) : color);
         boardToCreate.setPermissionEdit(true);
         boardToCreate.setPermissionManage(true);
-        observeOnce(syncManager.createBoard(viewModel.getCurrentAccount().getId(), boardToCreate), this, createdBoard -> {
+        observeOnce(syncManager.createBoard(mainViewModel.getCurrentAccount().getId(), boardToCreate), this, createdBoard -> {
             if (createdBoard == null) {
                 Snackbar.make(binding.coordinatorLayout, "Open Deck in web interface first!", Snackbar.LENGTH_LONG).show();
             } else {
@@ -424,17 +427,17 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
 
     @UiThread
     protected void setCurrentAccount(@NonNull Account account) {
-        viewModel.setCurrentAccount(account);
-        SingleAccountHelper.setCurrentAccount(getApplicationContext(), viewModel.getCurrentAccount().getName());
+        mainViewModel.setCurrentAccount(account);
+        SingleAccountHelper.setCurrentAccount(getApplicationContext(), mainViewModel.getCurrentAccount().getName());
         syncManager = new SyncManager(this);
 
-        Application.saveBrandColors(this, Color.parseColor(viewModel.getCurrentAccount().getColor()), Color.parseColor(viewModel.getCurrentAccount().getTextColor()));
-        Application.saveCurrentAccountId(this, viewModel.getCurrentAccount().getId());
-        if (viewModel.getCurrentAccount().isMaintenanceEnabled()) {
-            refreshCapabilities(viewModel.getCurrentAccount());
+        Application.saveBrandColors(this, Color.parseColor(mainViewModel.getCurrentAccount().getColor()), Color.parseColor(mainViewModel.getCurrentAccount().getTextColor()));
+        Application.saveCurrentAccountId(this, mainViewModel.getCurrentAccount().getId());
+        if (mainViewModel.getCurrentAccount().isMaintenanceEnabled()) {
+            refreshCapabilities(mainViewModel.getCurrentAccount());
         }
 
-        lastBoardId = Application.readCurrentBoardId(this, viewModel.getCurrentAccount().getId());
+        lastBoardId = Application.readCurrentBoardId(this, mainViewModel.getCurrentAccount().getId());
 
         if (boardsLiveData != null && boardsLiveDataObserver != null) {
             boardsLiveData.removeObserver(boardsLiveDataObserver);
@@ -467,13 +470,13 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         };
         boardsLiveData.observe(this, boardsLiveDataObserver);
 
-        ViewUtil.addAvatar(headerBinding.drawerCurrentAccount, viewModel.getCurrentAccount().getUrl(), viewModel.getCurrentAccount().getUserName(), R.mipmap.ic_launcher_round);
-        headerBinding.drawerUsernameFull.setText(viewModel.getCurrentAccount().getName());
+        ViewUtil.addAvatar(headerBinding.drawerCurrentAccount, mainViewModel.getCurrentAccount().getUrl(), mainViewModel.getCurrentAccount().getUserName(), R.mipmap.ic_launcher_round);
+        headerBinding.drawerUsernameFull.setText(mainViewModel.getCurrentAccount().getName());
         accountChooserActive = false;
         inflateAccountMenu();
         binding.drawerLayout.closeDrawer(GravityCompat.START);
-        DeckLog.verbose("Displaying maintenance mode info for " + viewModel.getCurrentAccount().getName() + ": " + viewModel.getCurrentAccount().isMaintenanceEnabled());
-        binding.infoBox.setVisibility(viewModel.getCurrentAccount().isMaintenanceEnabled() ? View.VISIBLE : View.GONE);
+        DeckLog.verbose("Displaying maintenance mode info for " + mainViewModel.getCurrentAccount().getName() + ": " + mainViewModel.getCurrentAccount().isMaintenanceEnabled());
+        binding.infoBox.setVisibility(mainViewModel.getCurrentAccount().isMaintenanceEnabled() ? View.VISIBLE : View.GONE);
     }
 
     private void refreshCapabilities(final Account account) {
@@ -509,15 +512,15 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     }
 
     protected void setCurrentBoard(@NonNull Board board) {
-        viewModel.setCurrentBoard(board);
-        viewModel.clearFilterInformation();
+        mainViewModel.setCurrentBoard(board);
+        filterViewModel.clearFilterInformation();
 
         lastBoardId = board.getLocalId();
-        Application.saveCurrentBoardId(this, viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId());
+        Application.saveCurrentBoardId(this, mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId());
 
         binding.toolbar.setTitle(board.getTitle());
 
-        if (viewModel.currentBoardHasEditPermission()) {
+        if (mainViewModel.currentBoardHasEditPermission()) {
             binding.fab.show();
             binding.addStackButton.setVisibility(View.VISIBLE);
         } else {
@@ -530,7 +533,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         binding.swipeRefreshLayout.setVisibility(View.VISIBLE);
 
 
-        syncManager.getStacksForBoard(viewModel.getCurrentAccount().getId(), board.getLocalId()).observe(MainActivity.this, (List<FullStack> fullStacks) -> {
+        syncManager.getStacksForBoard(mainViewModel.getCurrentAccount().getId(), board.getLocalId()).observe(MainActivity.this, (List<FullStack> fullStacks) -> {
             if (fullStacks == null) {
                 throw new IllegalStateException("Given List<FullStack> must not be null");
             }
@@ -547,7 +550,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
             int stackPositionInAdapter = 0;
             stackAdapter.setStacks(fullStacks);
 
-            long currentStackId = Application.readCurrentStackId(this, viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId());
+            long currentStackId = Application.readCurrentStackId(this, mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId());
             for (int i = 0; i < currentBoardStacksCount; i++) {
                 if (fullStacks.get(i).getLocalId() == currentStackId || currentStackId == NO_STACK_ID) {
                     stackPositionInAdapter = i;
@@ -633,7 +636,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         } else {
             switch (item.getItemId()) {
                 case MENU_ID_ABOUT:
-                    startActivityForResult(AboutActivity.createIntent(this, viewModel.getCurrentAccount()), MainActivity.ACTIVITY_ABOUT);
+                    startActivityForResult(AboutActivity.createIntent(this, mainViewModel.getCurrentAccount()), MainActivity.ACTIVITY_ABOUT);
                     break;
                 case MENU_ID_SETTINGS:
                     startActivityForResult(new Intent(this, SettingsActivity.class), MainActivity.ACTIVITY_SETTINGS);
@@ -653,7 +656,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         final MenuInflater inflater = getMenuInflater();
-        if (viewModel.currentBoardHasEditPermission()) {
+        if (mainViewModel.currentBoardHasEditPermission()) {
             final int currentViewPagerItem = binding.viewPager.getCurrentItem();
             inflater.inflate(R.menu.list_menu, menu);
             menu.findItem(R.id.rename_list).setVisible(currentBoardHasStacks);
@@ -665,7 +668,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
         }
         inflater.inflate(R.menu.main_menu, menu);
         menu.findItem(R.id.archived_cards).setVisible(false);
-        menu.findItem(R.id.filter).setIcon(viewModel.getFilterInformation().getValue() == null
+        menu.findItem(R.id.filter).setIcon(filterViewModel.getFilterInformation().getValue() == null
                 ? R.drawable.ic_filter_list_white_24dp
                 : R.drawable.ic_filter_list_active_white_24dp);
         return super.onCreateOptionsMenu(menu);
@@ -679,12 +682,12 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                 return true;
             }
             case R.id.archived_cards: {
-                startActivity(ArchivedCardsActvitiy.createIntent(this, viewModel.getCurrentAccount(), viewModel.getCurrentBoardLocalId(), viewModel.currentBoardHasEditPermission()));
+                startActivity(ArchivedCardsActvitiy.createIntent(this, mainViewModel.getCurrentAccount(), mainViewModel.getCurrentBoardLocalId(), mainViewModel.currentBoardHasEditPermission()));
                 return true;
             }
             case R.id.rename_list: {
                 final long stackId = stackAdapter.getItem(binding.viewPager.getCurrentItem()).getLocalId();
-                observeOnce(syncManager.getStack(viewModel.getCurrentAccount().getId(), stackId), MainActivity.this, fullStack ->
+                observeOnce(syncManager.getStack(mainViewModel.getCurrentAccount().getId(), stackId), MainActivity.this, fullStack ->
                         EditStackDialogFragment.newInstance(fullStack.getLocalId(), fullStack.getStack().getTitle())
                                 .show(getSupportFragmentManager(), EditStackDialogFragment.class.getCanonicalName()));
                 return true;
@@ -694,7 +697,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                 // TODO error handling
                 final int stackLeftPosition = binding.viewPager.getCurrentItem() - 1;
                 final long stackLeftId = stackAdapter.getItem(stackLeftPosition).getLocalId();
-                syncManager.swapStackOrder(viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId(), new Pair<>(stackId, stackLeftId));
+                syncManager.swapStackOrder(mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId(), new Pair<>(stackId, stackLeftId));
                 stackMoved = true;
                 return true;
             }
@@ -703,13 +706,13 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                 // TODO error handling
                 final int stackRightPosition = binding.viewPager.getCurrentItem() + 1;
                 final long stackRightId = stackAdapter.getItem(stackRightPosition).getLocalId();
-                syncManager.swapStackOrder(viewModel.getCurrentAccount().getId(), viewModel.getCurrentBoardLocalId(), new Pair<>(stackId, stackRightId));
+                syncManager.swapStackOrder(mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId(), new Pair<>(stackId, stackRightId));
                 stackMoved = true;
                 return true;
             }
             case R.id.delete_list: {
                 final long stackId = stackAdapter.getItem(binding.viewPager.getCurrentItem()).getLocalId();
-                observeOnce(syncManager.countCardsInStack(viewModel.getCurrentAccount().getId(), stackId), MainActivity.this, (numberOfCards) -> {
+                observeOnce(syncManager.countCardsInStack(mainViewModel.getCurrentAccount().getId(), stackId), MainActivity.this, (numberOfCards) -> {
                     if (numberOfCards != null && numberOfCards > 0) {
                         DeleteStackDialogFragment.newInstance(stackId, numberOfCards).show(getSupportFragmentManager(), DeleteStackDialogFragment.class.getCanonicalName());
                     } else {
@@ -724,7 +727,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     }
 
     protected void showFabIfEditPermissionGranted() {
-        if (viewModel.currentBoardHasEditPermission()) {
+        if (mainViewModel.currentBoardHasEditPermission()) {
             binding.fab.show();
         }
     }
@@ -785,7 +788,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
 
                                                     final Snackbar importSnackbar = Snackbar.make(binding.coordinatorLayout, R.string.account_is_getting_imported, Snackbar.LENGTH_INDEFINITE);
                                                     importSnackbar.show();
-                                                    importSyncManager.synchronize(new IResponseCallback<Boolean>(viewModel.getCurrentAccount()) {
+                                                    importSyncManager.synchronize(new IResponseCallback<Boolean>(mainViewModel.getCurrentAccount()) {
                                                         @Override
                                                         public void onResponse(Boolean response) {
                                                             importSnackbar.dismiss();
@@ -880,7 +883,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
                     @Override
                     public void onAvailable(@NonNull Network network) {
                         DeckLog.log("Got Network connection");
-                        syncManager.synchronize(new IResponseCallback<Boolean>(viewModel.getCurrentAccount()) {
+                        syncManager.synchronize(new IResponseCallback<Boolean>(mainViewModel.getCurrentAccount()) {
                             @Override
                             public void onResponse(Boolean response) {
                                 DeckLog.log("Auto-Sync after connection available successful");
@@ -921,7 +924,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     @Override
     public void onStackDeleted(Long stackLocalId) {
         long stackId = stackAdapter.getItem(binding.viewPager.getCurrentItem()).getLocalId();
-        observeOnce(syncManager.getStack(viewModel.getCurrentAccount().getId(), stackId), MainActivity.this, fullStack -> {
+        observeOnce(syncManager.getStack(mainViewModel.getCurrentAccount().getId(), stackId), MainActivity.this, fullStack -> {
             DeckLog.log("Delete stack #" + fullStack.getLocalId() + ": " + fullStack.getStack().getTitle());
             // TODO error handling
             syncManager.deleteStack(fullStack.getStack());
@@ -931,7 +934,7 @@ public class MainActivity extends BrandedActivity implements DeleteStackListener
     @Override
     public void onBoardDeleted(Board board) {
         final int index = this.boardsList.indexOf(board);
-        if (board.getLocalId().equals(viewModel.getCurrentBoardLocalId())) {
+        if (board.getLocalId().equals(mainViewModel.getCurrentBoardLocalId())) {
             if (index > 0) { // Select first board after deletion
                 setCurrentBoard(this.boardsList.get(0));
             } else if (this.boardsList.size() > 1) { // Select second board after deletion
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainViewModel.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainViewModel.java
index cebba655a..9017776da 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainViewModel.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/MainViewModel.java
@@ -1,82 +1,16 @@
 package it.niedermann.nextcloud.deck.ui;
 
-import androidx.annotation.NonNull;
-import androidx.lifecycle.LiveData;
-import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.ViewModel;
 
 import it.niedermann.nextcloud.deck.model.Account;
 import it.niedermann.nextcloud.deck.model.Board;
-import it.niedermann.nextcloud.deck.model.Label;
-import it.niedermann.nextcloud.deck.model.User;
-import it.niedermann.nextcloud.deck.model.enums.EDueType;
-import it.niedermann.nextcloud.deck.model.internal.FilterInformation;
-
-import static it.niedermann.nextcloud.deck.model.internal.FilterInformation.hasActiveFilter;
 
 @SuppressWarnings("WeakerAccess")
 public class MainViewModel extends ViewModel {
 
-    @NonNull
-    private MutableLiveData<FilterInformation> filterInformationDraft = new MutableLiveData<>(new FilterInformation());
-    @NonNull
-    private MutableLiveData<FilterInformation> filterInformation = new MutableLiveData<>();
     private Account currentAccount;
     private Board currentBoard;
 
-    public void publishFilterInformationDraft() {
-        this.filterInformation.postValue(hasActiveFilter(filterInformationDraft.getValue()) ? filterInformationDraft.getValue() : null);
-    }
-
-    public void clearFilterInformation() {
-        this.filterInformationDraft.postValue(new FilterInformation());
-        this.publishFilterInformationDraft();
-    }
-
-    @NonNull
-    public LiveData<FilterInformation> getFilterInformationDraft() {
-        return this.filterInformationDraft;
-    }
-
-    public void createFilterInformationDraft() {
-        this.filterInformationDraft.postValue(new FilterInformation(this.filterInformation.getValue()));
-    }
-
-    @NonNull
-    public LiveData<FilterInformation> getFilterInformation() {
-        return this.filterInformation;
-    }
-
-    public void setFilterInformationDraftDueType(@NonNull EDueType dueType) {
-        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
-        newDraft.setDueType(dueType);
-        this.filterInformationDraft.postValue(newDraft);
-    }
-
-    public void addFilterInformationDraftLabel(@NonNull Label label) {
-        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
-        newDraft.addLabel(label);
-        this.filterInformationDraft.postValue(newDraft);
-    }
-
-    public void addFilterInformationUser(@NonNull User user) {
-        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
-        newDraft.addUser(user);
-        this.filterInformationDraft.postValue(newDraft);
-    }
-
-    public void removeFilterInformationLabel(@NonNull Label label) {
-        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
-        newDraft.removeLabel(label);
-        this.filterInformationDraft.postValue(newDraft);
-    }
-
-    public void removeFilterInformationUser(@NonNull User user) {
-        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
-        newDraft.removeUser(user);
-        this.filterInformationDraft.postValue(newDraft);
-    }
-
     public Account getCurrentAccount() {
         return currentAccount;
     }
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterAssigneesFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterAssigneesFragment.java
index f26c51f99..6c7c1bd5c 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterAssigneesFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterAssigneesFragment.java
@@ -20,12 +20,14 @@ import it.niedermann.nextcloud.deck.ui.MainViewModel;
 
 import static it.niedermann.nextcloud.deck.persistence.sync.adapters.db.util.LiveDataHelper.observeOnce;
 import static it.niedermann.nextcloud.deck.util.DimensionUtil.dpToPx;
+import static java.util.Objects.requireNonNull;
 
 public class FilterAssigneesFragment extends Fragment implements SelectionListener<User> {
 
     private LiveData<FilterInformation> filterInformationDraft;
     private DialogFilterAssigneesBinding binding;
     private MainViewModel mainViewModel;
+    private FilterViewModel filterViewModel;
     private UserFilterAdapter userAdapter;
 
     @Nullable
@@ -34,11 +36,12 @@ public class FilterAssigneesFragment extends Fragment implements SelectionListen
 
         binding = DialogFilterAssigneesBinding.inflate(requireActivity().getLayoutInflater());
         mainViewModel = new ViewModelProvider(requireActivity()).get(MainViewModel.class);
+        filterViewModel = new ViewModelProvider(requireActivity()).get(FilterViewModel.class);
         final SyncManager syncManager = new SyncManager(requireActivity());
 
-        this.filterInformationDraft = mainViewModel.getFilterInformationDraft();
+        this.filterInformationDraft = filterViewModel.getFilterInformationDraft();
         observeOnce(syncManager.findProposalsForUsersToAssign(mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId()), requireActivity(), (users) -> {
-            userAdapter = new UserFilterAdapter(dpToPx(requireContext(), R.dimen.avatar_size), mainViewModel.getCurrentAccount(), users, this.filterInformationDraft.getValue().getUsers(), this);
+            userAdapter = new UserFilterAdapter(dpToPx(requireContext(), R.dimen.avatar_size), mainViewModel.getCurrentAccount(), users, requireNonNull(this.filterInformationDraft.getValue()).getUsers(), this);
             binding.users.setNestedScrollingEnabled(false);
             binding.users.setAdapter(userAdapter);
         });
@@ -48,11 +51,11 @@ public class FilterAssigneesFragment extends Fragment implements SelectionListen
 
     @Override
     public void onItemSelected(User item) {
-        mainViewModel.addFilterInformationUser(item);
+        filterViewModel.addFilterInformationUser(item);
     }
 
     @Override
     public void onItemDeselected(User item) {
-        mainViewModel.removeFilterInformationUser(item);
+        filterViewModel.removeFilterInformationUser(item);
     }
 }
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDialogFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDialogFragment.java
index ef6280c1c..0ea8f26cc 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDialogFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDialogFragment.java
@@ -19,7 +19,6 @@ import it.niedermann.nextcloud.deck.R;
 import it.niedermann.nextcloud.deck.databinding.DialogFilterBinding;
 import it.niedermann.nextcloud.deck.model.enums.EDueType;
 import it.niedermann.nextcloud.deck.model.internal.FilterInformation;
-import it.niedermann.nextcloud.deck.ui.MainViewModel;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedActivity;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedAlertDialogBuilder;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedDialogFragment;
@@ -27,7 +26,7 @@ import it.niedermann.nextcloud.deck.ui.branding.BrandedDialogFragment;
 public class FilterDialogFragment extends BrandedDialogFragment {
 
     private DialogFilterBinding binding;
-    private MainViewModel mainViewModel;
+    private FilterViewModel filterViewModel;
 
     private final static int[] tabTitles = new int[]{
             R.string.filter_tags_title,
@@ -40,7 +39,7 @@ public class FilterDialogFragment extends BrandedDialogFragment {
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        mainViewModel = new ViewModelProvider(requireActivity()).get(MainViewModel.class);
+        filterViewModel = new ViewModelProvider(requireActivity()).get(FilterViewModel.class);
 
         final AlertDialog.Builder dialogBuilder = new BrandedAlertDialogBuilder(requireContext());
 
@@ -48,7 +47,7 @@ public class FilterDialogFragment extends BrandedDialogFragment {
         binding.viewPager.setAdapter(new TabsPagerAdapter(getChildFragmentManager(), getLifecycle()));
         binding.viewPager.setOffscreenPageLimit(tabTitles.length);
 
-        LiveData<FilterInformation> filterInformationDraft = mainViewModel.getFilterInformationDraft();
+        LiveData<FilterInformation> filterInformationDraft = filterViewModel.getFilterInformationDraft();
         new TabLayoutMediator(binding.tabLayout, binding.viewPager, (tab, position) -> {
             switch (position) {
                 case 0:
@@ -84,14 +83,14 @@ public class FilterDialogFragment extends BrandedDialogFragment {
             tab.setText(tabTitles[position]);
         }).attach();
 
-        mainViewModel.createFilterInformationDraft();
+        filterViewModel.createFilterInformationDraft();
 
         return dialogBuilder
                 .setTitle(R.string.simple_filter)
                 .setView(binding.getRoot())
                 .setNeutralButton(android.R.string.cancel, null)
-                .setNegativeButton(R.string.simple_clear, (a, b) -> mainViewModel.clearFilterInformation())
-                .setPositiveButton(R.string.simple_filter, (a, b) -> mainViewModel.publishFilterInformationDraft())
+                .setNegativeButton(R.string.simple_clear, (a, b) -> filterViewModel.clearFilterInformation())
+                .setPositiveButton(R.string.simple_filter, (a, b) -> filterViewModel.publishFilterInformationDraft())
                 .create();
     }
 
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDuedateFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDuedateFragment.java
index 43b399139..654e95744 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDuedateFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterDuedateFragment.java
@@ -15,23 +15,22 @@ import androidx.lifecycle.ViewModelProvider;
 import it.niedermann.nextcloud.deck.databinding.DialogFilterDuedateBinding;
 import it.niedermann.nextcloud.deck.model.enums.EDueType;
 import it.niedermann.nextcloud.deck.model.internal.FilterInformation;
-import it.niedermann.nextcloud.deck.ui.MainViewModel;
 
 public class FilterDuedateFragment extends Fragment implements AdapterView.OnItemSelectedListener {
 
     private LiveData<FilterInformation> filterInformationDraft;
     private DialogFilterDuedateBinding binding;
-    private MainViewModel mainViewModel;
+    private FilterViewModel filterViewModel;
     private OverdueFilterAdapter overdueAdapter;
 
     @Nullable
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         binding = DialogFilterDuedateBinding.inflate(requireActivity().getLayoutInflater());
-        mainViewModel = new ViewModelProvider(requireActivity()).get(MainViewModel.class);
+        filterViewModel = new ViewModelProvider(requireActivity()).get(FilterViewModel.class);
         overdueAdapter = new OverdueFilterAdapter(requireContext());
         binding.overdue.setAdapter(overdueAdapter);
-        this.filterInformationDraft = mainViewModel.getFilterInformationDraft();
+        this.filterInformationDraft = filterViewModel.getFilterInformationDraft();
         binding.overdue.setSelection(overdueAdapter.getPosition(this.filterInformationDraft.getValue().getDueType()));
         binding.overdue.setOnItemSelectedListener(this);
         return binding.getRoot();
@@ -39,11 +38,11 @@ public class FilterDuedateFragment extends Fragment implements AdapterView.OnIte
 
     @Override
     public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
-        mainViewModel.setFilterInformationDraftDueType(overdueAdapter.getItem(position));
+        filterViewModel.setFilterInformationDraftDueType(overdueAdapter.getItem(position));
     }
 
     @Override
     public void onNothingSelected(AdapterView<?> parent) {
-        mainViewModel.setFilterInformationDraftDueType(EDueType.NO_FILTER);
+        filterViewModel.setFilterInformationDraftDueType(EDueType.NO_FILTER);
     }
 }
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterLabelsFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterLabelsFragment.java
index b2e5e5c58..64384d89f 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterLabelsFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterLabelsFragment.java
@@ -18,12 +18,14 @@ import it.niedermann.nextcloud.deck.persistence.sync.SyncManager;
 import it.niedermann.nextcloud.deck.ui.MainViewModel;
 
 import static it.niedermann.nextcloud.deck.persistence.sync.adapters.db.util.LiveDataHelper.observeOnce;
+import static java.util.Objects.requireNonNull;
 
 public class FilterLabelsFragment extends Fragment implements SelectionListener<Label> {
 
     private LiveData<FilterInformation> filterInformationDraft;
     private DialogFilterLabelsBinding binding;
     private MainViewModel mainViewModel;
+    private FilterViewModel filterViewModel;
     private LabelFilterAdapter labelAdapter;
 
     @Nullable
@@ -31,11 +33,12 @@ public class FilterLabelsFragment extends Fragment implements SelectionListener<
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         binding = DialogFilterLabelsBinding.inflate(requireActivity().getLayoutInflater());
         mainViewModel = new ViewModelProvider(requireActivity()).get(MainViewModel.class);
+        filterViewModel = new ViewModelProvider(requireActivity()).get(FilterViewModel.class);
         final SyncManager syncManager = new SyncManager(requireActivity());
 
-        this.filterInformationDraft = mainViewModel.getFilterInformationDraft();
+        this.filterInformationDraft = filterViewModel.getFilterInformationDraft();
         observeOnce(syncManager.findProposalsForLabelsToAssign(mainViewModel.getCurrentAccount().getId(), mainViewModel.getCurrentBoardLocalId()), requireActivity(), (labels) -> {
-            labelAdapter = new LabelFilterAdapter(labels, this.filterInformationDraft.getValue().getLabels(), this);
+            labelAdapter = new LabelFilterAdapter(labels, requireNonNull(this.filterInformationDraft.getValue()).getLabels(), this);
             binding.labels.setNestedScrollingEnabled(false);
             binding.labels.setAdapter(labelAdapter);
         });
@@ -44,11 +47,11 @@ public class FilterLabelsFragment extends Fragment implements SelectionListener<
 
     @Override
     public void onItemSelected(Label item) {
-        mainViewModel.addFilterInformationDraftLabel(item);
+        filterViewModel.addFilterInformationDraftLabel(item);
     }
 
     @Override
     public void onItemDeselected(Label item) {
-        mainViewModel.removeFilterInformationLabel(item);
+        filterViewModel.removeFilterInformationLabel(item);
     }
 }
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterViewModel.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterViewModel.java
new file mode 100644
index 000000000..e5734bdda
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterViewModel.java
@@ -0,0 +1,75 @@
+package it.niedermann.nextcloud.deck.ui.filter;
+
+import androidx.annotation.NonNull;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.ViewModel;
+
+import it.niedermann.nextcloud.deck.model.Label;
+import it.niedermann.nextcloud.deck.model.User;
+import it.niedermann.nextcloud.deck.model.enums.EDueType;
+import it.niedermann.nextcloud.deck.model.internal.FilterInformation;
+
+import static it.niedermann.nextcloud.deck.model.internal.FilterInformation.hasActiveFilter;
+
+@SuppressWarnings("WeakerAccess")
+public class FilterViewModel extends ViewModel {
+
+    @NonNull
+    private MutableLiveData<FilterInformation> filterInformationDraft = new MutableLiveData<>(new FilterInformation());
+    @NonNull
+    private MutableLiveData<FilterInformation> filterInformation = new MutableLiveData<>();
+
+    public void publishFilterInformationDraft() {
+        this.filterInformation.postValue(hasActiveFilter(filterInformationDraft.getValue()) ? filterInformationDraft.getValue() : null);
+    }
+
+    public void clearFilterInformation() {
+        this.filterInformationDraft.postValue(new FilterInformation());
+        this.publishFilterInformationDraft();
+    }
+
+    @NonNull
+    public LiveData<FilterInformation> getFilterInformationDraft() {
+        return this.filterInformationDraft;
+    }
+
+    public void createFilterInformationDraft() {
+        this.filterInformationDraft.postValue(new FilterInformation(this.filterInformation.getValue()));
+    }
+
+    @NonNull
+    public LiveData<FilterInformation> getFilterInformation() {
+        return this.filterInformation;
+    }
+
+    public void setFilterInformationDraftDueType(@NonNull EDueType dueType) {
+        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
+        newDraft.setDueType(dueType);
+        this.filterInformationDraft.postValue(newDraft);
+    }
+
+    public void addFilterInformationDraftLabel(@NonNull Label label) {
+        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
+        newDraft.addLabel(label);
+        this.filterInformationDraft.postValue(newDraft);
+    }
+
+    public void addFilterInformationUser(@NonNull User user) {
+        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
+        newDraft.addUser(user);
+        this.filterInformationDraft.postValue(newDraft);
+    }
+
+    public void removeFilterInformationLabel(@NonNull Label label) {
+        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
+        newDraft.removeLabel(label);
+        this.filterInformationDraft.postValue(newDraft);
+    }
+
+    public void removeFilterInformationUser(@NonNull User user) {
+        FilterInformation newDraft = new FilterInformation(filterInformationDraft.getValue());
+        newDraft.removeUser(user);
+        this.filterInformationDraft.postValue(newDraft);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/stack/StackFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/stack/StackFragment.java
index a221fcbff..def22c3f7 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/stack/StackFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/stack/StackFragment.java
@@ -24,6 +24,7 @@ import it.niedermann.nextcloud.deck.ui.MainViewModel;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedFragment;
 import it.niedermann.nextcloud.deck.ui.card.CardAdapter;
 import it.niedermann.nextcloud.deck.ui.card.SelectCardListener;
+import it.niedermann.nextcloud.deck.ui.filter.FilterViewModel;
 
 public class StackFragment extends BrandedFragment implements DragAndDropTab<CardAdapter> {
 
@@ -60,11 +61,12 @@ public class StackFragment extends BrandedFragment implements DragAndDropTab<Car
         binding = FragmentStackBinding.inflate(inflater, container, false);
         activity = requireActivity();
 
-        final MainViewModel viewModel = new ViewModelProvider(activity).get(MainViewModel.class);
+        final MainViewModel mainViewModel = new ViewModelProvider(activity).get(MainViewModel.class);
+        final FilterViewModel filterViewModel = new ViewModelProvider(activity).get(FilterViewModel.class);
 
         syncManager = new SyncManager(activity);
 
-        adapter = new CardAdapter(requireContext(), viewModel.getCurrentAccount(), viewModel.getCurrentBoardLocalId(), stackId, viewModel.currentBoardHasEditPermission(), syncManager, this, (requireActivity() instanceof SelectCardListener) ? (SelectCardListener) requireActivity() : null);
+        adapter = new CardAdapter(requireContext(), mainViewModel.getCurrentAccount(), mainViewModel.getCurrentBoardLocalId(), stackId, mainViewModel.currentBoardHasEditPermission(), syncManager, this, (requireActivity() instanceof SelectCardListener) ? (SelectCardListener) requireActivity() : null);
         binding.recyclerView.setAdapter(adapter);
 
         if (onScrollListener != null) {
@@ -79,7 +81,7 @@ public class StackFragment extends BrandedFragment implements DragAndDropTab<Car
             });
         }
 
-        if (!viewModel.currentBoardHasEditPermission()) {
+        if (!mainViewModel.currentBoardHasEditPermission()) {
             binding.emptyContentView.hideDescription();
         }
 
@@ -92,12 +94,12 @@ public class StackFragment extends BrandedFragment implements DragAndDropTab<Car
             }
         });
 
-        cardsLiveData = syncManager.getFullCardsForStack(viewModel.getCurrentAccount().getId(), stackId, viewModel.getFilterInformation().getValue());
+        cardsLiveData = syncManager.getFullCardsForStack(mainViewModel.getCurrentAccount().getId(), stackId, filterViewModel.getFilterInformation().getValue());
         cardsLiveData.observe(getViewLifecycleOwner(), cardsObserver);
 
-        viewModel.getFilterInformation().observe(getViewLifecycleOwner(), (filterInformation -> {
+        filterViewModel.getFilterInformation().observe(getViewLifecycleOwner(), (filterInformation -> {
             cardsLiveData.removeObserver(cardsObserver);
-            cardsLiveData = syncManager.getFullCardsForStack(viewModel.getCurrentAccount().getId(), stackId, filterInformation);
+            cardsLiveData = syncManager.getFullCardsForStack(mainViewModel.getCurrentAccount().getId(), stackId, filterInformation);
             cardsLiveData.observe(getViewLifecycleOwner(), cardsObserver);
         }));