review: fix nullability and visibility of settings

briar-android/src/main/java/org/briarproject/briar/android/settings/AvatarPreference.java

@@ -5,6 +5,7 @@ import android.util.AttributeSet;
 import android.view.View;
 import android.widget.TextView;
 
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.R;
 
 import androidx.annotation.Nullable;
@@ -14,6 +15,7 @@ import de.hdodenhof.circleimageview.CircleImageView;
 
 import static org.briarproject.briar.android.view.AuthorView.setAvatar;
 
+@NotNullByDefault
 public class AvatarPreference extends Preference {
 
 	@Nullable

briar-android/src/main/java/org/briarproject/briar/android/settings/ConnectionsStore.java

@@ -5,6 +5,8 @@ import org.briarproject.bramble.api.settings.SettingsManager;
 
 import java.util.concurrent.Executor;
 
+import androidx.annotation.Nullable;
+
 import static org.briarproject.bramble.api.plugin.Plugin.PREF_PLUGIN_ENABLE;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_MOBILE;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK;
@@ -49,12 +51,12 @@ class ConnectionsStore extends SettingsStore {
 	}
 
 	@Override
-	public void putInt(String key, int value) {
+	public void putString(String key, @Nullable String value) {
 		// translate between Android UI pref keys and bramble keys
 		if (key.equals(PREF_KEY_TOR_NETWORK)) {
-			super.putInt(PREF_TOR_NETWORK, value);
+			super.putString(PREF_TOR_NETWORK, value);
 		} else {
-			throw new AssertionError();
+			throw new AssertionError(key);
 		}
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/settings/DisplayFragment.java

@@ -16,6 +16,7 @@ import java.util.Locale;
 import java.util.logging.Logger;
 
 import androidx.core.text.TextUtilsCompat;
+import androidx.fragment.app.FragmentActivity;
 import androidx.preference.ListPreference;
 import androidx.preference.Preference;
 import androidx.preference.PreferenceFragmentCompat;
@@ -25,6 +26,7 @@ import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
 import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
 import static android.os.Build.VERSION.SDK_INT;
 import static androidx.core.view.ViewCompat.LAYOUT_DIRECTION_LTR;
+import static java.util.Objects.requireNonNull;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
@@ -43,11 +45,11 @@ public class DisplayFragment extends PreferenceFragmentCompat {
 	public void onCreatePreferences(Bundle bundle, String s) {
 		addPreferencesFromResource(R.xml.settings_display);
 
-		ListPreference language = findPreference(PREF_LANGUAGE);
+		ListPreference language = requireNonNull(findPreference(PREF_LANGUAGE));
 		setLanguageEntries(language);
 		language.setOnPreferenceChangeListener(this::onLanguageChanged);
 
-		ListPreference theme = findPreference(PREF_THEME);
+		ListPreference theme = requireNonNull(findPreference(PREF_THEME));
 		setThemeEntries(theme);
 		theme.setOnPreferenceChangeListener(this::onThemeChanged);
 	}
@@ -121,7 +123,8 @@ public class DisplayFragment extends PreferenceFragmentCompat {
 
 	private boolean onThemeChanged(Preference preference, Object newValue) {
 		// activate new theme
-		UiUtils.setTheme(getActivity(), (String) newValue);
+		FragmentActivity activity = requireActivity();
+		UiUtils.setTheme(activity, (String) newValue);
 		// bring up parent activity, so it can change its theme as well
 		// upstream bug: https://issuetracker.google.com/issues/38352704
 		Intent intent = new Intent(getActivity(), ENTRY_ACTIVITY);
@@ -129,9 +132,9 @@ public class DisplayFragment extends PreferenceFragmentCompat {
 		startActivity(intent);
 		// bring this activity back to the foreground
 		// TODO maybe tell the activity here to relaunch this fragment?
-		intent = new Intent(getActivity(), getActivity().getClass());
+		intent = new Intent(getActivity(), activity.getClass());
 		startActivity(intent);
-		getActivity().finish();
+		activity.finish();
 		return true;
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/settings/NotificationsManager.java

@@ -37,7 +37,6 @@ import static org.briarproject.briar.api.android.AndroidNotificationManager.PREF
 import static org.briarproject.briar.api.android.AndroidNotificationManager.PREF_NOTIFY_SOUND;
 import static org.briarproject.briar.api.android.AndroidNotificationManager.PREF_NOTIFY_VIBRATION;
 
-
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
 class NotificationsManager {
@@ -64,7 +63,7 @@ class NotificationsManager {
 
 	private volatile String ringtoneName, ringtoneUri;
 
-	public NotificationsManager(Context ctx,
+	NotificationsManager(Context ctx,
 			SettingsManager settingsManager,
 			Executor dbExecutor) {
 		this.ctx = ctx;
@@ -153,7 +152,7 @@ class NotificationsManager {
 		return ringtoneName;
 	}
 
-	public String getRingtoneUri() {
+	String getRingtoneUri() {
 		return ringtoneUri;
 	}
 }

briar-android/src/main/java/org/briarproject/briar/android/settings/SettingsStore.java

@@ -11,7 +11,6 @@ import java.util.logging.Logger;
 import androidx.annotation.Nullable;
 import androidx.preference.PreferenceDataStore;
 
-import static java.util.Objects.requireNonNull;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
@@ -21,8 +20,6 @@ import static org.briarproject.bramble.util.LogUtils.now;
 
 /**
  * A custom PreferenceDataStore that stores settings in Briar's encrypted DB.
- * <p>
- * Warning: This expects all strings to be integers and stores them as such.
  */
 @NotNullByDefault
 class SettingsStore extends PreferenceDataStore {
@@ -61,8 +58,11 @@ class SettingsStore extends PreferenceDataStore {
 
 	@Override
 	public void putString(String key, @Nullable String value) {
-		int integer = Integer.parseInt(requireNonNull(value));
-		putInt(key, integer);
+		if (LOG.isLoggable(INFO))
+			LOG.info("Store string setting: " + key + "=" + value);
+		Settings s = new Settings();
+		s.put(key, value);
+		storeSettings(s);
 	}
 
 	private void storeSettings(Settings s) {

briar-android/src/main/java/org/briarproject/briar/android/settings/SettingsViewModel.java

@@ -42,6 +42,7 @@ import java.util.logging.Logger;
 
 import javax.inject.Inject;
 
+import androidx.annotation.AnyThread;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 
@@ -117,7 +118,7 @@ class SettingsViewModel extends DbViewModel implements EventListener {
 		this.authorManager = authorManager;
 		this.ioExecutor = ioExecutor;
 		this.featureFlags = featureFlags;
-		this.settingsStore = new SettingsStore(settingsManager, dbExecutor,
+		settingsStore = new SettingsStore(settingsManager, dbExecutor,
 				SETTINGS_NAMESPACE);
 		torSummaryProvider = new TorSummaryProvider(getApplication(),
 				locationUtils, circumventionProvider);
@@ -195,6 +196,7 @@ class SettingsViewModel extends DbViewModel implements EventListener {
 		}
 	}
 
+	@AnyThread
 	private void updateSettings(Settings settings) {
 		screenLockEnabled.postValue(settings.getBoolean(PREF_SCREEN_LOCK,
 				false));

briar-android/src/main/java/org/briarproject/briar/android/settings/TorSummaryProvider.java

@@ -20,7 +20,7 @@ class TorSummaryProvider implements SummaryProvider<ListPreference> {
 	private final LocationUtils locationUtils;
 	private final CircumventionProvider circumventionProvider;
 
-	public TorSummaryProvider(Context ctx,
+	TorSummaryProvider(Context ctx,
 			LocationUtils locationUtils,
 			CircumventionProvider circumventionProvider) {
 		this.ctx = ctx;