some cleaning

app/src/main/java/app/fedilab/android/mastodon/activities/ComposeActivity.java

@@ -44,6 +44,7 @@ import android.view.WindowManager;
 import android.widget.LinearLayout;
 import android.widget.Toast;
 
+import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.ActionBar;
 import androidx.appcompat.app.AlertDialog;
@@ -158,31 +159,21 @@ public class ComposeActivity extends BaseActivity implements ComposeAdapter.Mana
     private String editMessageId;
 
     private static int visibilityToNumber(String visibility) {
-        switch (visibility) {
+        return switch (visibility) {
-            case "public":
+            case "unlisted" -> 2;
-                return 3;
+            case "private" -> 1;
-            case "unlisted":
+            case "direct" -> 0;
-                return 2;
+            default -> 3;
-            case "private":
+        };
-                return 1;
-            case "direct":
-                return 0;
-        }
-        return 3;
     }
 
     private static String visibilityToString(int visibility) {
-        switch (visibility) {
+        return switch (visibility) {
-            case 3:
+            case 2 -> "unlisted";
-                return "public";
+            case 1 -> "private";
-            case 2:
+            case 0 -> "direct";
-                return "unlisted";
+            default -> "public";
-            case 1:
+        };
-                return "private";
-            case 0:
-                return "direct";
-        }
-        return "public";
     }
 
     public static String getVisibility(BaseAccount account, String defaultVisibility) {
@@ -208,13 +199,6 @@ public class ComposeActivity extends BaseActivity implements ComposeAdapter.Mana
 
     }
 
-    @Override
-    public void onBackPressed() {
-        if (binding.recyclerView.getVisibility() == View.VISIBLE) {
-            storeDraftWarning();
-        }
-        super.onBackPressed();
-    }
 
     private void storeDraftWarning() {
         if (statusDraft == null) {
@@ -778,6 +762,15 @@ public class ComposeActivity extends BaseActivity implements ComposeAdapter.Mana
                 composeAdapter.addSharing(null, null, sharedDescription, null, sharedContent, null);
             }
         }
+
+        getOnBackPressedDispatcher().addCallback(new OnBackPressedCallback(true) {
+            @Override
+            public void handleOnBackPressed() {
+                if (binding.recyclerView.getVisibility() == View.VISIBLE) {
+                    storeDraftWarning();
+                }
+            }
+        });
     }
 
     @Override
@@ -1032,7 +1025,7 @@ public class ComposeActivity extends BaseActivity implements ComposeAdapter.Mana
                 .into(binding.mediaPreview);
         if (attachment.description != null) {
             binding.mediaDescription.setText(attachment.description);
-            binding.mediaDescription.setSelection(binding.mediaDescription.getText().length());
+            binding.mediaDescription.setSelection(Objects.requireNonNull(binding.mediaDescription.getText()).length());
         }
         binding.mediaDescription.setFilters(new InputFilter[]{new InputFilter.LengthFilter(1500)});
         binding.mediaDescription.requestFocus();
@@ -1043,13 +1036,13 @@ public class ComposeActivity extends BaseActivity implements ComposeAdapter.Mana
             binding.description.setVisibility(View.GONE);
             actionBar.show();
             binding.recyclerView.setVisibility(View.VISIBLE);
-            composeAdapter.openDescriptionActivity(true, binding.mediaDescription.getText().toString().trim(), holder, attachment, messagePosition, mediaPosition);
+            composeAdapter.openDescriptionActivity(true, Objects.requireNonNull(binding.mediaDescription.getText()).toString().trim(), holder, attachment, messagePosition, mediaPosition);
         });
         binding.mediaCancel.setOnClickListener(v -> {
             binding.description.setVisibility(View.GONE);
             actionBar.show();
             binding.recyclerView.setVisibility(View.VISIBLE);
-            composeAdapter.openDescriptionActivity(false, binding.mediaDescription.getText().toString().trim(), holder, attachment, messagePosition, mediaPosition);
+            composeAdapter.openDescriptionActivity(false, Objects.requireNonNull(binding.mediaDescription.getText()).toString().trim(), holder, attachment, messagePosition, mediaPosition);
         });
     }
 

app/src/main/java/app/fedilab/android/mastodon/activities/CustomSharingActivity.java

@@ -28,6 +28,7 @@ import android.widget.Toast;
 import androidx.preference.PreferenceManager;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.Set;
 
 import app.fedilab.android.R;
@@ -126,7 +127,7 @@ public class CustomSharingActivity extends BaseBarActivity implements OnCustomSh
         binding.setCustomSharingSave.setOnClickListener(v -> {
             // obtain title, description, keywords
             title = binding.setCustomSharingTitle.getText().toString();
-            keywords = binding.setCustomSharingKeywords.getText().toString();
+            keywords = Objects.requireNonNull(binding.setCustomSharingKeywords.getText()).toString();
             CharSequence comma_only = ",";
             CharSequence space_only = " ";
             CharSequence double_space = "  ";
@@ -194,38 +195,38 @@ public class CustomSharingActivity extends BaseBarActivity implements OnCustomSh
             String param_value = uri.getQueryParameter(param_name);
             if (param_value != null)
                 switch (param_value) {
-                    case "${url}":
+                    case "${url}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_url);
-                        break;
+                    }
-                    case "${title}":
+                    case "${title}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, title);
-                        break;
+                    }
-                    case "${source}":
+                    case "${source}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_source);
-                        break;
+                    }
-                    case "${id}":
+                    case "${id}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_id);
-                        break;
+                    }
-                    case "${description}":
+                    case "${description}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_content);
-                        break;
+                    }
-                    case "${keywords}":
+                    case "${keywords}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, keywords);
-                        break;
+                    }
-                    case "${creator}":
+                    case "${creator}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_creator);
-                        break;
+                    }
-                    case "${thumbnailurl}":
+                    case "${thumbnailurl}" -> {
                         paramFound = true;
                         builder.appendQueryParameter(param_name, bundle_thumbnailurl);
-                        break;
+                    }
                 }
             if (!paramFound) {
                 builder.appendQueryParameter(param_name, param_value);

app/src/main/java/app/fedilab/android/mastodon/activities/EditProfileActivity.java

@@ -41,6 +41,7 @@ import com.google.android.material.textfield.TextInputEditText;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Locale;
+import java.util.Objects;
 
 import app.fedilab.android.BaseMainActivity;
 import app.fedilab.android.BuildConfig;
@@ -115,18 +116,10 @@ public class EditProfileActivity extends BaseBarActivity {
         if (currentAccount.mastodon_account.source != null) {
             binding.sensitive.setChecked(currentAccount.mastodon_account.source.sensitive);
             switch (currentAccount.mastodon_account.source.privacy) {
-                case "public":
+                case "public" -> binding.visibilityPublic.setChecked(true);
-                    binding.visibilityPublic.setChecked(true);
+                case "unlisted" -> binding.visibilityUnlisted.setChecked(true);
-                    break;
+                case "private" -> binding.visibilityPrivate.setChecked(true);
-                case "unlisted":
+                case "direct" -> binding.visibilityDirect.setChecked(true);
-                    binding.visibilityUnlisted.setChecked(true);
-                    break;
-                case "private":
-                    binding.visibilityPrivate.setChecked(true);
-                    break;
-                case "direct":
-                    binding.visibilityDirect.setChecked(true);
-                    break;
             }
         } else {
             binding.sensitive.setVisibility(View.GONE);
@@ -318,8 +311,8 @@ public class EditProfileActivity extends BaseBarActivity {
         LinkedHashMap<Integer, Field.FieldParams> fields = new LinkedHashMap<>();
         for (int i = 0; i < binding.fieldsContainer.getChildCount(); i++) {
             Field.FieldParams field = new Field.FieldParams();
-            field.name = ((TextInputEditText) binding.fieldsContainer.getChildAt(i).findViewById(R.id.name)).getText().toString().trim();
+            field.name = Objects.requireNonNull(((TextInputEditText) binding.fieldsContainer.getChildAt(i).findViewById(R.id.name)).getText()).toString().trim();
-            field.value = ((TextInputEditText) binding.fieldsContainer.getChildAt(i).findViewById(R.id.value)).getText().toString().trim();
+            field.value = Objects.requireNonNull(((TextInputEditText) binding.fieldsContainer.getChildAt(i).findViewById(R.id.value)).getText()).toString().trim();
             fields.put(i, field);
         }
         return fields;
@@ -334,8 +327,8 @@ public class EditProfileActivity extends BaseBarActivity {
             accountsVM.updateCredentials(BaseMainActivity.currentInstance, BaseMainActivity.currentToken,
                             binding.discoverable.isChecked(),
                             binding.bot.isChecked(),
-                            binding.displayName.getText().toString().trim(),
+                            Objects.requireNonNull(binding.displayName.getText()).toString().trim(),
-                            binding.bio.getText().toString(),
+                            Objects.requireNonNull(binding.bio.getText()).toString(),
                             binding.locked.isChecked(),
                             getPrivacy(),
                             binding.sensitive.isChecked(),

app/src/main/java/app/fedilab/android/mastodon/activities/FilterActivity.java

@@ -75,27 +75,13 @@ public class FilterActivity extends BaseBarActivity implements FilterAdapter.Del
             @Override
             public void onItemSelected(AdapterView<?> parent1, View view, int position1, long id) {
                 switch (position1) {
-                    case 0:
+                    case 0 -> expire[0] = -1;
-                        expire[0] = -1;
+                    case 1 -> expire[0] = 1800;
-                        break;
+                    case 2 -> expire[0] = 3600;
-                    case 1:
+                    case 3 -> expire[0] = 21600;
-                        expire[0] = 1800;
+                    case 4 -> expire[0] = 43200;
-                        break;
+                    case 5 -> expire[0] = 86400;
-                    case 2:
+                    case 6 -> expire[0] = 604800;
-                        expire[0] = 3600;
-                        break;
-                    case 3:
-                        expire[0] = 21600;
-                        break;
-                    case 4:
-                        expire[0] = 43200;
-                        break;
-                    case 5:
-                        expire[0] = 86400;
-                        break;
-                    case 6:
-                        expire[0] = 604800;
-                        break;
                 }
             }
 
@@ -128,21 +114,12 @@ public class FilterActivity extends BaseBarActivity implements FilterAdapter.Del
             if (filter.context != null) {
                 for (String val : filter.context) {
                     switch (val) {
-                        case "home":
+                        case "home" -> popupAddFilterBinding.contextHome.setChecked(true);
-                            popupAddFilterBinding.contextHome.setChecked(true);
+                        case "public" -> popupAddFilterBinding.contextPublic.setChecked(true);
-                            break;
+                        case "notifications" ->
-                        case "public":
+                                popupAddFilterBinding.contextNotification.setChecked(true);
-                            popupAddFilterBinding.contextPublic.setChecked(true);
+                        case "thread" -> popupAddFilterBinding.contextConversation.setChecked(true);
-                            break;
+                        case "account" -> popupAddFilterBinding.contextProfiles.setChecked(true);
-                        case "notifications":
-                            popupAddFilterBinding.contextNotification.setChecked(true);
-                            break;
-                        case "thread":
-                            popupAddFilterBinding.contextConversation.setChecked(true);
-                            break;
-                        case "account":
-                            popupAddFilterBinding.contextProfiles.setChecked(true);
-                            break;
                     }
                 }
             }
@@ -193,7 +170,7 @@ public class FilterActivity extends BaseBarActivity implements FilterAdapter.Del
                         canBeSent = false;
                     }
                 }
-                if (popupAddFilterBinding.addTitle.getText().toString().trim().isEmpty()) {
+                if (Objects.requireNonNull(popupAddFilterBinding.addTitle.getText()).toString().trim().isEmpty()) {
                     popupAddFilterBinding.addTitle.setError(context.getString(R.string.cannot_be_empty));
                     canBeSent = false;
                 }

app/src/main/java/app/fedilab/android/mastodon/activities/FollowRequestActivity.java

@@ -94,11 +94,8 @@ public class FollowRequestActivity extends BaseActivity {
 
         binding.loadingNextAccounts.setVisibility(View.GONE);
         if (accountList != null && accounts != null && accounts.accounts != null && accounts.accounts.size() > 0) {
-            int startId = 0;
             //There are some statuses present in the timeline
-            if (accountList.size() > 0) {
+            int startId = accountList.size();
-                startId = accountList.size();
-            }
             flagLoading = accounts.pagination.max_id == null;
             accountList.addAll(accounts.accounts);
             max_id = accounts.pagination.max_id;

app/src/main/java/app/fedilab/android/mastodon/activities/FollowedTagActivity.java

@@ -21,6 +21,7 @@ import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 
+import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.FragmentManager;
@@ -82,12 +83,27 @@ public class FollowedTagActivity extends BaseBarActivity implements FollowedTagA
                         binding.notContent.setVisibility(View.VISIBLE);
                     }
                 });
+        getOnBackPressedDispatcher().addCallback(new OnBackPressedCallback(true) {
+            @Override
+            public void handleOnBackPressed() {
+                if (canGoBack) {
+                    canGoBack = false;
+                    ThemeHelper.slideViewsToRight(binding.fragmentContainer, binding.recyclerView, () -> {
+                        if (fragmentMastodonTimeline != null) {
+                            fragmentMastodonTimeline.onDestroyView();
+                        }
+                    });
+                    setTitle(R.string.followed_tags);
+                    invalidateOptionsMenu();
+                }
+            }
+        });
     }
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         if (item.getItemId() == android.R.id.home) {
-            onBackPressed();
+            getOnBackPressedDispatcher().onBackPressed();
             return true;
         } else if (item.getItemId() == R.id.action_unfollow && tag != null) {
             AlertDialog.Builder alt_bld = new MaterialAlertDialogBuilder(FollowedTagActivity.this);
@@ -170,21 +186,6 @@ public class FollowedTagActivity extends BaseBarActivity implements FollowedTagA
         return true;
     }
 
-    @Override
-    public void onBackPressed() {
-        if (canGoBack) {
-            canGoBack = false;
-            ThemeHelper.slideViewsToRight(binding.fragmentContainer, binding.recyclerView, () -> {
-                if (fragmentMastodonTimeline != null) {
-                    fragmentMastodonTimeline.onDestroyView();
-                }
-            });
-            setTitle(R.string.followed_tags);
-            invalidateOptionsMenu();
-        } else {
-            super.onBackPressed();
-        }
-    }
 
     @Override
     public void click(Tag tag) {

app/src/main/java/app/fedilab/android/mastodon/activities/InstanceActivity.java

@@ -37,6 +37,8 @@ import androidx.preference.PreferenceManager;
 import com.bumptech.glide.Glide;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 
+import java.util.Objects;
+
 import app.fedilab.android.BaseMainActivity;
 import app.fedilab.android.R;
 import app.fedilab.android.activities.MainActivity;
@@ -82,7 +84,7 @@ public class InstanceActivity extends DialogFragment {
             binding.maxChar.setText(String.valueOf(maxCharCustom));
         }
         binding.close.setOnClickListener(view -> {
-                    String max_char = binding.maxChar.getText().toString();
+                    String max_char = Objects.requireNonNull(binding.maxChar.getText()).toString();
                     SharedPreferences.Editor editor = sharedpreferences.edit();
                     if (!max_char.isEmpty()) {
                         try {

app/src/main/java/app/fedilab/android/mastodon/activities/MastodonListActivity.java

@@ -15,6 +15,7 @@ package app.fedilab.android.mastodon.activities;
  * see <http://www.gnu.org/licenses>. */
 
 
+import android.annotation.SuppressLint;
 import android.content.Intent;
 import android.os.Bundle;
 import android.text.Editable;
@@ -25,6 +26,7 @@ import android.view.MenuItem;
 import android.view.MotionEvent;
 import android.view.View;
 
+import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.FragmentManager;
@@ -39,6 +41,7 @@ import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 
 import app.fedilab.android.BaseMainActivity;
 import app.fedilab.android.BuildConfig;
@@ -127,6 +130,22 @@ public class MastodonListActivity extends BaseBarActivity implements MastodonLis
                         }
                     });
                 });
+
+        getOnBackPressedDispatcher().addCallback(new OnBackPressedCallback(true) {
+            @Override
+            public void handleOnBackPressed() {
+                if (canGoBack) {
+                    canGoBack = false;
+                    ThemeHelper.slideViewsToRight(binding.fragmentContainer, binding.recyclerView, () -> {
+                        if (fragmentMastodonTimeline != null) {
+                            fragmentMastodonTimeline.onDestroyView();
+                        }
+                    });
+                    setTitle(R.string.action_lists);
+                    invalidateOptionsMenu();
+                }
+            }
+        });
     }
 
 
@@ -142,10 +161,11 @@ public class MastodonListActivity extends BaseBarActivity implements MastodonLis
         invalidateOptionsMenu();
     }
 
+    @SuppressLint("ClickableViewAccessibility")
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         if (item.getItemId() == android.R.id.home) {
-            onBackPressed();
+            getOnBackPressedDispatcher().onBackPressed();
             return true;
         } else if (item.getItemId() == R.id.action_user_mute_home) {
             AlertDialog.Builder dialogBuilder = new MaterialAlertDialogBuilder(MastodonListActivity.this);
@@ -344,7 +364,7 @@ public class MastodonListActivity extends BaseBarActivity implements MastodonLis
             dialogBuilder.setView(popupAddListBinding.getRoot());
             popupAddListBinding.addList.setFilters(new InputFilter[]{new InputFilter.LengthFilter(255)});
             popupAddListBinding.addList.setText(mastodonList.title);
-            popupAddListBinding.addList.setSelection(popupAddListBinding.addList.getText().length());
+            popupAddListBinding.addList.setSelection(Objects.requireNonNull(popupAddListBinding.addList.getText()).length());
             dialogBuilder.setPositiveButton(R.string.validate, (dialog, id) -> {
                 if (popupAddListBinding.addList.getText() != null && popupAddListBinding.addList.getText().toString().trim().length() > 0) {
                     timelinesVM.updateList(
@@ -459,20 +479,4 @@ public class MastodonListActivity extends BaseBarActivity implements MastodonLis
         }
         return true;
     }
-
-    @Override
-    public void onBackPressed() {
-        if (canGoBack) {
-            canGoBack = false;
-            ThemeHelper.slideViewsToRight(binding.fragmentContainer, binding.recyclerView, () -> {
-                if (fragmentMastodonTimeline != null) {
-                    fragmentMastodonTimeline.onDestroyView();
-                }
-            });
-            setTitle(R.string.action_lists);
-            invalidateOptionsMenu();
-        } else {
-            super.onBackPressed();
-        }
-    }
 }

app/src/main/java/app/fedilab/android/mastodon/activities/ProfileActivity.java

@@ -17,7 +17,6 @@ package app.fedilab.android.mastodon.activities;
 
 import static app.fedilab.android.BaseMainActivity.currentAccount;
 
-import android.app.DownloadManager;
 import android.content.BroadcastReceiver;
 import android.content.ClipData;
 import android.content.ClipboardManager;
@@ -28,7 +27,6 @@ import android.content.SharedPreferences;
 import android.content.res.ColorStateList;
 import android.graphics.drawable.Animatable;
 import android.graphics.drawable.Drawable;
-import android.os.Build;
 import android.os.Bundle;
 import android.text.SpannableString;
 import android.text.Spanned;
@@ -1226,20 +1224,18 @@ public class ProfileActivity extends BaseActivity {
                     target = account.id;
                 }
                 switch (doActionAccount) {
-                    case BLOCK:
+                    case BLOCK ->
-                        accountsVM.block(BaseMainActivity.currentInstance, BaseMainActivity.currentToken, target)
+                            accountsVM.block(BaseMainActivity.currentInstance, BaseMainActivity.currentToken, target)
-                                .observe(ProfileActivity.this, relationShip -> {
+                                    .observe(ProfileActivity.this, relationShip -> {
-                                    this.relationship = relationShip;
+                                        this.relationship = relationShip;
-                                    updateAccount();
+                                        updateAccount();
-                                });
+                                    });
-                        break;
+                    case UNBLOCK ->
-                    case UNBLOCK:
+                            accountsVM.unblock(BaseMainActivity.currentInstance, BaseMainActivity.currentToken, target)
-                        accountsVM.unblock(BaseMainActivity.currentInstance, BaseMainActivity.currentToken, target)
+                                    .observe(ProfileActivity.this, relationShip -> {
-                                .observe(ProfileActivity.this, relationShip -> {
+                                        this.relationship = relationShip;
-                                    this.relationship = relationShip;
+                                        updateAccount();
-                                    updateAccount();
+                                    });
-                                });
-                        break;
                 }
                 dialog.dismiss();
             });

app/src/main/java/app/fedilab/android/mastodon/activities/ReportActivity.java

@@ -28,6 +28,7 @@ import androidx.recyclerview.widget.LinearLayoutManager;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 import app.fedilab.android.BaseMainActivity;
 import app.fedilab.android.R;
@@ -291,7 +292,7 @@ public class ReportActivity extends BaseBarActivity {
             if (fragment != null) {
                 statusIds = fragment.getCheckedStatusesId();
             }
-            comment = binding.reportMessage.getText().toString();
+            comment = Objects.requireNonNull(binding.reportMessage.getText()).toString();
             binding.actionButton.setEnabled(false);
             accountsVM.report(BaseMainActivity.currentInstance, BaseMainActivity.currentToken, account.id, category, statusIds, ruleIds, comment, forward)
                     .observe(ReportActivity.this, report -> {

app/src/main/java/app/fedilab/android/mastodon/activities/StatusInfoActivity.java

@@ -145,11 +145,8 @@ public class StatusInfoActivity extends BaseActivity {
             if (!checkRemotely) {
                 fetchRelationShip(accounts.accounts, position);
             }
-            int startId = 0;
             //There are some statuses present in the timeline
-            if (accountList.size() > 0) {
+            int startId = accountList.size();
-                startId = accountList.size();
-            }
             accountList.addAll(accounts.accounts);
             max_id = accounts.pagination.max_id;
             flagLoading = accounts.pagination.max_id == null;

app/src/main/java/app/fedilab/android/mastodon/activities/TrendsActivity.java

@@ -71,11 +71,9 @@ public class TrendsActivity extends BaseBarActivity {
                 Fragment fragment;
                 if (binding.trendsViewpager.getAdapter() != null) {
                     fragment = (Fragment) binding.trendsViewpager.getAdapter().instantiateItem(binding.trendsViewpager, tab.getPosition());
-                    if (fragment instanceof FragmentMastodonTimeline) {
+                    if (fragment instanceof FragmentMastodonTimeline fragmentMastodonTimeline) {
-                        FragmentMastodonTimeline fragmentMastodonTimeline = ((FragmentMastodonTimeline) fragment);
                         fragmentMastodonTimeline.scrollToTop();
-                    } else if (fragment instanceof FragmentMastodonTag) {
+                    } else if (fragment instanceof FragmentMastodonTag fragmentMastodonTag) {
-                        FragmentMastodonTag fragmentMastodonTag = ((FragmentMastodonTag) fragment);
                         fragmentMastodonTag.scrollToTop();
                     }
                 }

app/src/main/java/app/fedilab/android/mastodon/broadcastreceiver/NetworkStateReceiver.java

@@ -25,7 +25,7 @@ import java.util.Set;
 
 
 /**
- * Original work from https://stackoverflow.com/a/25873554
+ * Original work from <a href="https://stackoverflow.com/a/25873554">stackoverflow</a>
  */
 public class NetworkStateReceiver extends BroadcastReceiver {
 

app/src/main/java/app/fedilab/android/mastodon/broadcastreceiver/ToastMessage.java

@@ -31,18 +31,14 @@ public class ToastMessage extends BroadcastReceiver {
             String content = b.getString(Helper.RECEIVE_TOAST_CONTENT, null);
             if (type != null && content != null) {
                 switch (type) {
-                    case Helper.RECEIVE_TOAST_TYPE_ERROR:
+                    case Helper.RECEIVE_TOAST_TYPE_ERROR ->
-                        Toasty.error(context, content, Toasty.LENGTH_SHORT).show();
+                            Toasty.error(context, content, Toasty.LENGTH_SHORT).show();
-                        break;
+                    case Helper.RECEIVE_TOAST_TYPE_WARNING ->
-                    case Helper.RECEIVE_TOAST_TYPE_WARNING:
+                            Toasty.warning(context, content, Toasty.LENGTH_SHORT).show();
-                        Toasty.warning(context, content, Toasty.LENGTH_SHORT).show();
+                    case Helper.RECEIVE_TOAST_TYPE_INFO ->
-                        break;
+                            Toasty.info(context, content, Toasty.LENGTH_SHORT).show();
-                    case Helper.RECEIVE_TOAST_TYPE_INFO:
+                    case Helper.RECEIVE_TOAST_TYPE_SUCCESS ->
-                        Toasty.info(context, content, Toasty.LENGTH_SHORT).show();
+                            Toasty.success(context, content, Toasty.LENGTH_SHORT).show();
-                        break;
-                    case Helper.RECEIVE_TOAST_TYPE_SUCCESS:
-                        Toasty.success(context, content, Toasty.LENGTH_SHORT).show();
-                        break;
                 }
             }
         }

app/src/main/java/app/fedilab/android/mastodon/ui/fragment/settings/FragmentComposeSettings.java

@@ -14,6 +14,7 @@ package app.fedilab.android.mastodon.ui.fragment.settings;
  * You should have received a copy of the GNU General Public License along with Fedilab; if not,
  * see <http://www.gnu.org/licenses>. */
 
+import android.annotation.SuppressLint;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 
@@ -23,6 +24,7 @@ import androidx.preference.PreferenceFragmentCompat;
 import androidx.preference.PreferenceManager;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.Set;
 
 import app.fedilab.android.BaseMainActivity;
@@ -37,6 +39,7 @@ public class FragmentComposeSettings extends PreferenceFragmentCompat implements
         createPref();
     }
 
+    @SuppressLint("ApplySharedPref")
     private void createPref() {
 
         SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(requireActivity());
@@ -83,7 +86,7 @@ public class FragmentComposeSettings extends PreferenceFragmentCompat implements
 
     @Override
     public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-        if (key.equalsIgnoreCase(getString(R.string.SET_WATERMARK_TEXT))) {
+        if (Objects.requireNonNull(key).equalsIgnoreCase(getString(R.string.SET_WATERMARK_TEXT))) {
             SharedPreferences.Editor editor = sharedPreferences.edit();
             editor.putString(getString(R.string.SET_WATERMARK_TEXT) + BaseMainActivity.currentUserID + BaseMainActivity.currentInstance, sharedPreferences.getString(getString(R.string.SET_WATERMARK_TEXT), null));
             editor.apply();
@@ -94,14 +97,14 @@ public class FragmentComposeSettings extends PreferenceFragmentCompat implements
     public void onResume() {
         super.onResume();
 
-        getPreferenceScreen().getSharedPreferences()
+        Objects.requireNonNull(getPreferenceScreen().getSharedPreferences())
                 .registerOnSharedPreferenceChangeListener(this);
     }
 
     @Override
     public void onPause() {
         super.onPause();
-        getPreferenceScreen().getSharedPreferences()
+        Objects.requireNonNull(getPreferenceScreen().getSharedPreferences())
                 .unregisterOnSharedPreferenceChangeListener(this);
     }